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Short of bio

2. DAY-1 DAY-2
➔REPRODUCTION
➔GENETICS AND
EVOLUTION
➔BIOTECHNOLOGY
➔BIOLOGY IN HUMAN
WELFARE
➔ECOLOGY
➔CELL : STRUCTURE
AND FUNCTIONS
➔HUMAN PHYSIOLOGY
➔PLANT PHYSIOLOGY
➔DIVERSITY IN THE
LIVING WORLD
➔STRUCTURAL
ORGANISATION IN
PLANTS AND ANIMALS

3. 8.1 What is a Ce!?
8.2 Ce! Theory
8.3 An Overview of Ce!
8.4 Prokaryotic Ce!s
8.5 Eukaryotic Ce!s
Cell: The Unit of Life
Ce!
Living organisms
No ce!
Inanimate thing
Unicellular Multicellular
8.1 What is a Cell?
Unicellular
organisms
independent existence
performing essential life functions
fundamental structural & functional unit of a! living organisms
Anton Von Leeuwenhoek
Robert Brown
electron microscope
cell structures details
Robert Hooke
cell
live cell
nucleus
plants ce!s
animals ce!s
8.2 Cell Theory
1838, Matthias Schleiden { German botanist}
1839, Theodore Schwann {British Zoologist}
Rudolf Virchow1855, ce!s divided & new ce!s
pre-existing ce!s (Omnis ce!ula-e ce!ula)
"rst explained
modified
1) a! living organisms

ce!s products of ce!s
2) a! ce!s
pre-existing ce!s.
Final cell theory
Cell overview
Cell membrane
Cytoplasm
DNA
Both pro/ eukaryotes Prokaryotes Eukaryotes
Plants
Animals
Cell wall
No membrane
bound oraganells
membrane
bound oraganells
Ribosome
Cytoplasm
Chloroplast
Mitochondria
Rough ER
non-membrane
centrosomeRibosome
cell divisionProtein
No cell wall
Cells size
bacteria
3 to 5 m
largest cell
ostrich egg
smallest cell
Mycoplasmas
0.3 m
human RBC
7.0 m
longest cell
Nerve cell
Shapes of ce!s
Disc like
Polygonal
Irregular
Columnar
Thread like
Cuboid
Cells shapes
8.4 Prokaryotic Cells
bacteriablue-green algae mycoplasmaPPLO
smallermultiply faster
four basic shapes of bacteria
bacillus (rod like)
coccus (spherical)
vibrio (comma)
spirillum (spiral)
cell wall
cytoplasm
genomic DNA +
plasmids antibiotics
resistance
ribosomes
mesosome infoldings
No cell wall
8.4.1 Cell Envelope and its Modifications
bacterial cells envelope
glycocalyx
cell wall
plasma membrane
Also protection
Gram
positive
Gram
negative
loose sheath { slime layer }
thick ,tough {capsule}
shape /support
selectively permeable
mesosome
vesicles
tubules
lamellae
cell wall
formation
DNA
replication
distribution to
daughter
respiration
secretion
processes
Plasma
membranous
extensions
Structure
Function
no stainstain
Bacterial cells
motile
non-motile
flagellum filament
hook
basal body
longest cell surface outside
Glycocalyx
Mesosome
Chromatophores
{cyanobacteria}
Pili
elongated tubular
structures
sma! bristle like "bres
bacteria
Function
rocks in streams
host
attach
8.4.2 Ribosomes
15 nm by 20 nm size
site of protein synthesis
Several ribosomessingle mRNA
polyribosomespolysome
mRNA proteins
Reserve materialcytoplasm
e.g. phosphate, cyanophycean, glycogen
granules.
green
photosynthetic
bacteria
Gas vacuoles
No role in motility
translate
blue green
purple
Inclusion Bodies
In
To
70S
50S
30S units
Fimbriae
8.5 Eukaryotic Cells
protists plants animals fungi
membrane bound organelles
organised nucleus with nuclear envelope.
complex locomotory & cytoskeletal structures
genetic material into chromosomes
All are not identical.
Plant cell
cell walls
plastids
large central vacuole
animal cells
centrioles
Features
Unique
Plant ce! Animal ce!
8.5.1 Cell / plasma Membrane
lipids proteins cholesterol carbohydrate
phospholipids
bilayer
polar head
hydrophobic tails
.
ratio of protein &
lipid varies
different cell types.
human
erythrocyte
52 % protein &
40 % lipids
Singer and
Nicolson (1972)
fluid
mosaic model
fluidity
movement of proteins
A!ows
cell growth
transport of molecules across
formation of intercellular
junctions
secretion endocytosis
cell division
passive transport
No energy/ ATP
osmosis
along concentration
gradient
higher
lower
concentration
Active Transport
against concentration
gradient
Use energy/ ATP
e.g., Na+/K+ Pump
semipermeable
membrane
8.5.2 Cell Wall
non-living rigid structure
outer covering plasma membrane
cell shape
protection
cell-to-cell interaction
barrier
cellulose
galactans
mannas
minerals like
calcium
carbonate
Function
Algae cell wall
Made up Plant cell wall
cellulose
hemicellulose
pectins
proteins
Made up
primary wall
secondary wall
growth
young plant cell wall
diminishes as cell matures
cell wall + middle lamellae
neighbouring cells cytoplasm
connect holds/glues
{calcium pectate }
inner cell side
For
8.5.3 Endomembrane System
endoplasmic
reticulum (ER)
golgi complex
lysosomes
vacuoles
functions are coordinated
Smooth
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4. 8.5.3.1 The Endoplasmic Reticulum (ER)
network or reticulum of tiny tubular structures
luminal (inside ER)
extra luminal (cytoplasm)
endoplasmic reticulum + ribosomes = rough endoplasmic reticulum (RER)
endoplasmic reticulum + no ribosomes = smooth endoplasmic reticulum (SER)
protein synthesis and secretionsynthesis
animal cells
steroidal
hormones
lipid
8.5.3.2 Golgi apparatus
Camillo Golgi (1898)
reticular structures near nucleus
Golgi bodies
#at, disc-shaped sacs or cisternae of 0.5Hm to 1.0Hm diameter
functions
convex cis or forming face
concave trans or maturing face
di$erent, but
interconnected
packaging materials
delivering
In / out of cell
Comes
Leaves
proteins modi"ed
Ribosome RER
Protein / package materials
glycoproteins &
glycolipids formations
proteins modification
Cis /trans
8.5.3.3 Lysosomes
membrane bound vesicular
structures
lysosomal
vesicles
hydrolytic enzymes
(hydrolases - lipases, proteases, carbohydrases)
carbohydrates, proteins, lipids and nucleic acids
digest
by process of packaging in
Golgi apparatus
Formed
8.5.3.4 Vacuoles
membrane-bound space
water, sap, excretory products
(single membrane)
ions & other materials
against concentration
gradients
plant vacuole 90 % cell volume
Amoeba contractile vacuole
osmoregulation & excretion.
(single membrane)
In many ce!s, as in protists,
food vacuoles
engul"ng food particles
By
concentration is higher in vacuole than cytoplasm.
8.5.4 Mitochondria
(sing.: mitochondrion),
sausage-shaped or
cylindrical
diameter of 0.2-1.0 m
(average 0.5Hm)
length 1.0-4.1 m
Each mitochondrion
double
membrane-bound
forms continuous
limiting boundaryBoth Have own specific enzymes as per function
sites of aerobic
respirationce!ular energy
(ATP)
power
houses of
ce!
single circular DNA
few RNA molecules,
ribosomes (70S)
Increases as ce!
activity
sing
infoldings
increase
surface area
dense
homogeneous
components for proteins
synthesis
Have
divide by
"ssion
Forms
not easily visible
microscope
stained
8.5.5 Plastidsa! plant ce!s & euglenoides.
speci"c pigments, speci"c colours to plants
chloroplasts, chromoplasts ,leucoplasts
chlorophy! & carotenoid pigments
photosynthesis
traps light energy
chloroplasts
chromoplasts
carotene & xanthophy!s etc
yellow, orange or red
fat soluble carotenoid pigments
Gives Color
leucoplasts
Amyloplastselaioplastsaleuroplasts
store carbohydrates
(starch), e.g., potato
store oils and
fats
store proteins
colourless plastids
large
microscope
easily
mesophyll leaves
length (5-10um) and
width (2-4um)
20-40 per green
alga cell
chloroplasts
lens-shaped
oval,
spherical, discoid
even ribbon-like
1 per Chlamydomonas
cell
double membrane
bound
ribosomes (70S)
less permeable
flattened membranous
sacs
stacks/ piles coins
connecting
synthesis of
carbohydrates and
proteins
small, double-stranded circular
DNA molecules
ribosomes
Have
enzymes
Chlorophyll
pigments
8.5.6 Ribosomes
George Palade
(1953)
electron microscope
ribonucleic acid (RNA)
proteins
granular structures
(No membrane)
eukaryotic ribosomes {80S }prokaryotic ribosomes { 70S}
60S and 40S
50S and 30S
S' (Svedberg's Unit) stands for sedimentation coefficient
indirectly measure density / size
8.5.7 Cytoskeleton
network of "lamentous proteinaceous structures
microtubules
micro!laments
intermediate !laments
mechanical support
motility
cell shape
Figure 8.10 Section of cilia/#age!a showing di$erent parts
(a) Electron micrograph
(b) Diagrammatic representation of internal structure
In cytoplasm
Function
Structure
8.5.8 Cilia and FlagellaCilia (sing.cilium) and "age#a (sing."age#um)
hair-like outgrowths of ce# membrane
Cilia
small
Flage!a
longer
cell movement
different from prokaryotes cell or surrounding fluid
oars movement
emerge from basal bodies
axoneme
plasma membrane.
microtubules
Radially
microtubules
centrally
microtubules
radial spokes
linkers
9 2
9
9
2
Raid
8.5.9 Centrosome and Centrioles
two cylindrical
amorphous
pericentriolar materials
perpendicular( cartwheel)
9 peripheral triplet fibrils
proteinaceous
hub
protein
Function
basal body
cilia flagella spindle fibres
spindle apparatus
cell division
{animal cells}
Forms
Tubilin protein
8.5.10 Nucleus
First Robert Brown( 1831)
nuclear matrix + 1 or more spherical bodies =nucleoli (sing.nucleolus)
Later Fle"ing
nucleus stained
chromatin
nucleus
nuclear envelope
(10 to 50 nm) perinuclear space
Inner membrane
continuous with RER
nuclear pores
outer membrane
fusion
passage
RNA and protein
In /out of nucleus
erythrocytes {many mammals }

sieve tube cells {vascular plants}
lack nucleus
If cell dividing
chromosomes in place of nucleus
If cell not dividing
Chromatin
nucleoprotein fibres
interphase nucleus
spherical structures
Normally. 1 nucleus per cell
More protein synthesisMore nucleus
nucleolus + chromatin = nucleoplasm
site for active ribosomal
RNA synthesis
Chromatin
some non-histone proteins
RNA
DNA+proteins
histones
single human ce!
2 mtr long DNA thread
distributed
46(23 pairs) chromosomes
Every chromosome (visible only in dividing ce!s)
constriction /centromere
disc shaped
4 types of chromosomes
chromatid chromatid
chromosome
Both Hold
by
Based on
metacentric chromosome
middle centromere
two equal
sub-metacentric
slightly away
from middle
one shorter & one longer
acrocentric
close to its
end
extremely short &very long
telocentric
terminal
non-staining
sma# fragment
8.5.11 Microbodies
membrane bound minute vesicles
plant animal cells
enzymes
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5. Cell Cycle and Cell Division
C
10.1 Cell Cycle
10.2 M Phase
10.3 Significance of Mitosis
10.4 Meiosis
10.5 Significance of Meiosis
single cell large organisms
Cell cycle & Division
cell characteristics
Growth
reproduction
10.1 Cell Cycle
ce! division
DNA replication
ce! growth
coordinated
correct cell
cycle,division
ce! growth
(cytoplasmic increase)
duplicates
synthesises
divides
Ce! genome
Ce! constituents
two daughter
Ce!
ce!
continuous process
DNA synthesis
Only ce! division
genetic
control
For
human ce!s
10.1.1 Phases of Cell Cycle
Yeast
90 min
duration vary
organism to organism
cell to cell
interphase
95%
M Phase
5%
23 hr 1 hr
24 hours
Interphase
M Phase (Mitosis phase)
cell cycle
G1 phase (Gap 1)
S phase (Synthesis)
G2 phase (Gap 2)
ce! growth DNA replication
Subdivided
Preparation
( resting phase)
interval
metabolica!y active
continuously grows
no DNA replication
G1 phase
S or synthesis phase
DNA synthesis or replication
DNA doubles
If 2C then 4C
no increase in chromosome
If 2n then also 2n
mitosis
DNA replication initiation
replicate DNA
duplicate centriole
nucleus
cytoplasm
In animal
cells
In
In
G2 phase
proteins synthesised
ce! growth continues
interphase
G1 S G2
Chromosome
DNA
2n
2C
2n 2n
4C
4C
'

In animals
mitotic ce! division
diploid somatic ce!s
But some
mitotic ce! division
haploid ce!s
eg.male honey bees
plants
mitotic ce! division
haploid & diploid ce!s
Only
Both
replace ce!s
No ce! division
(e.g heart ce!s)
adult animals
injury or cell death Some exit G1 phase
quiescent stage (GO)
inactive stage
no proliferate
If needed then cell division
cell division
metabolically active
Some
M Phase
starts(karyokinesis)
nuclear division cytoplasm division
ends (cytokinesis)
cell division or mitosis
most dramatic period
reorganisation a! ce! components
chromosomes same equational division
parent
progeny ce!s
Prophase
Metaphase
Anaphase
Telophase
initiation of chromosomal condensation
centrosome ce! opposite poles
compact mitotic chromosomes
2 chromatids with centromere
Leads to
move
Prophase
Karyokinesis involves 4 stages
chromosome untangled chromatin condensation
During
2 asters with spindle "bres
mitotic apparatus
forms
golgi
ER
nucleolus
nuclear envelope
do not
show
Metaphase
nuclear envelope
chromosomes morphology easily studied
one pole
opposite pole
chromatid
sister chromatid
spindle "bres
spindle "bres
kinetochore
Disc shape
chromosomes
complete
disintegration
condensation
a! chromosomes at equator
Centromere
metaphase plate
Attach
Anaphase
Centromeres split and chromatids separate
Chromatids move to opposite poles
If 2n then 4n
Telophase
Chromosomes cluster
Chromosomes cluster
Nuclear envelope
2 daughter nuclei
forming
spindle pole
spindle pole
No discrete elements
Nucleolus
golgi
ER
refor
m
Cytokinesis
I
cytoplasm division 2 daughter ce!s
plasma membrane
Animal cytokinesis
furrow plasma membrane
deepens joins centre
2 cell cytoplasm
dividing
Di#erent bcz of ce! wa!
formation
two adjacent ce!s
distributed
mitochondria
plastids
2 daughter
ce!s
multinucleate [ only karyokinesis]
syncytium formation
(e.g., liquid endosperm in coconut).
new ce! wa!
ce!-plate (middle lame!a )
Plant cytokinesis
Significance of Mitosis
Mitosis
diploid ce!s only
some lower plants,
insects
Mitosis
haploid ce!
diploid daughter ce!s
genetica!y same
equational division
restore nucleo-
cytoplasmic ratio
cell repair
Mitosis Significance
cell replace
epidermis upper layer
gut lining
blood cellsmeristematic tissues
apical lateral cambium
All life
multicellular
organisms
growth
Meiosis
Sperm
Egg
(n)
(n)
Male ce! (2n)
Female ce! (2n)
Chromosome half
Fertization
Zygote (2n)
gametogenesis in plants and animals
Diploid DiploidHaploid
4 haploid ce!s
meiosis1
meiosis 2
nuclear & Ce! division
DNA replication
S phase
Both
only once
Ce!
Somatic cell
Germ cell
Mitosis Meiosis
46
46
23
46
46
23
23232323
M 1
M2
Reductional division
Equational division
Equational division
2 diploid ce!s
identical sister
chromatids
b4 meiosis I
homologous chromosomes +
non-sister chromatids
=2 haploid cells
like mitoti division equal chromosome
Meiosis I
Prophase I
Metaphase I
Anaphase I
Telophase I
Meiosis II
Prophase II
Metaphase Il
Anaphase II
Telophase II
Meiosis I
Prophase I
longer
more complex than mitosis
subdivided
Leptotene
Zygotene
Pachytene
Diplotene
Diakinesis
based on
chromosomal
behaviour
visible light microscope
compaction continues
chromosomes
Centromere
leptotene
chromosomes pairing (synapsis)
homologous chromosomes
Electron micrographs synaptonemal complex
bivalent or tetrad
4 chromatids( bivalent
chromosomes ) clearly as tetrads
recombination nodules
synaptonemal
complex
enzyme {recombinase}
Zygotene
Pachytene
some vertebrates(oocytes ) diplotene for months/ yrs
synaptonemal
complex
X-shaped
recombined homologous
chromosomes bivalents
except at crossovers sites
separation dissolution
chiasmata terminalisation
nucleolus disappears
nuclear envelope broken
chromosomes separation
Diplotene
Diakinesis
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6. bivalent chromosomes at equatorial plate
Metaphase I
spindle( microtubules)
kinetochore
homologous chromosomes
Attach
homologous chromosomes separate
Sti! sister chromatids with centromeres
Anaphase I
many chromosomes cant reach interphase nucleus
stage b/w 2 meiotic divisions interkinesis
Telophase I
nuclear membrane & nucleolus reappear
cytokinesis
short lived
no DNA replication
dyad ce!s
resembles mitosis( equal chromosome)
initiated
after cytokinesis
b4 chromosomes fu!y elongated
Meiosis!II
Prophase 2
nuclear membrane disappears
chromosomes again compact
Metaphase 2
chromosomes align at equator
microtubules( opposite poles) spindle
kinetochores( sister chromatids)
attached
Anaphase 2
Centromeres split & chromatids separate
Chromatids move to opposite poles
microtubules shortening
by
kinetochores
microtubules
attached
Telophase 2
Reforms nuclear envelope
cytokinesis
tetrad ce!s
4 haploid daughter ce!s
Results
Significance of Meiosis
increases genetic variations
very important for evolution
+
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7. Breathing and Exchange of Gases
1 Respiratory Organs
2 Mechanism of Breathing
3 Exchange of Gases
4 Transport of Gases
5 Regulation of Respiration
6 Disorders of Respiratory System
1 Respiratory Organs
2 Mechanism of Breathing
3 Exchange of Gases
4 Transport of Gases
5 Regulation of Respiration
6 Disorders of Respiratory System
Oxygen (O2)
break down glucose,
amino acids, fatty
acids, etc
Carbon dioxide (CO2)
!
released during
catabolic reactions
harmful
Useful
Inspiration Exspiration Breathing
Exchange of O2 with CO2
Air
Body
RESPIRATORY ORGANS
RESPIRATORY ORGANSEXAMPLES
Entire body surface
(Simple diffusion)
Skin or moist cuticle
(cutaneous respiration)
Tracheal tubes
Gills
(Branchial respiration)
lungs
"
(Pulmonary respiration)
Lower invertebrates sponges,
coelenterates, flatworms etc.
Earthworms, frog
#

Insects
$

Aquatic arthropod & molluscs
%

Fishes
&
Reptiles, birds
'
,mammals
(depends on habitats & level of organisation)
Human Respiratory System
External nostrils pair
(

Upper lip
nasal passage
nasal chamber
pharynx
laRyNx
pHarYnX
common passage food
)
Air
*

cartilaginous box / sound box
GloTtIS
During
swallowing
EpiGlOTtiS
thin elastic cartilaginous flap
TraChEa
straight tube
upto
mid-thoracic cavity
divides
5th thoracic vertebra Right
left
Tracheae primary secondary tertiary bronchi initial bronchioles
incomplete
cartilaginous rings
supported by
thin terminal
bronchioles
very thin, irregular-walled
vascularised bag-like (alveoli)
LunGs "
branching network of bronchi + bronchioles+ alveoli
reduces friction
outer pleural membrane
contact with thoracic lining
inner pleural membrane
contact with lung surface
lungs
"
in thoracic (air tight) chamber
ThoRAciC cHamBEr
dorsally
by vertebral
column
ventrally
by sternum
laterally
by ribs &
diaphragm
(dome-shaped)
vertebral column
( backbone)
sternum
ribs
diaphragm
Change in thoracic cavity volume
Change in lung (pulmonary) cavity volume
actual diffusion of O2 & CO2
b/w blood & atmospheric air.
Human respiratory system
Conducting part Respiratory or exchange part
External nostrils
(
to
terminal bronchioles
alveoli & their ducts
transports air to alveoli
clears it from foreign particles
humidifies
FunCtIoNs
LocATiOnS
1) Breathing or pulmonary ventilation atmospheric air in and CO2 rich alveolar air is out
2) Diffusion of gases O2 & CO2 across alveolar membrane
3) Transport of gases by blood.
4) Diffusion of O2 & CO2 b/w blood & tissues.
5) Utilisation of O2 by cells for catabolic reactions & release CO2 (cellular respiration )
Respiration involves following steps
Mechanism of Breathing
creating pressure gradient
alveolar air out
atmospheric air in
inspiration expiration
lungs
"
atmosphere
*

b/w
intra-pulmonary
"
< atmospheric pressure,
- pressure
intra-pulmonary
"
>atmospheric pressure,
+ pressure
Diaphragm
antero-posterior axis
lifts up ribs & sternum
inter-costal muscles
thoracic chamber volume inc
dorso-ventral axis
coNtRAcTs
increase in pulmonary volume
air into
"

intra-pulmonary
"
< atmospheric
pressure
Inspiration
Inter-costal muscles & diaphragm relax
diaphragm & sternum its normal position
Thoracic volume decreases
Pulmonary volume decreases.
Air moves out.
Expiration
intra-pulmonary
"
>atmospheric pressure,

healthy human breathes 12-16 times/minute
spirometer
clinical assessment of
pulmonary functions.
Ability to increase
abdomen additional muscles
inspiration &
expiration strength
By
Respiratory Volumes
inspired or expired during normal respiration.
healthy
+
inspire or expire
Additional inspire by forcible inspiration
Additional expire by forcible expiration
remaining in lungs
"
after forcible expiration
500 mL
6000 to 8000 mL
mL of air per min
2500 mL to 3000 mL
Inspiratory Reserve Volume (RV)
Expiratory Reserve Volume (ERV)
1000 mL to 1100 mL
1100 mL to 1200 mL
Tidal Volume (TV)
Residual Volume (RV)
Respiratory capacities
Inspirat!y Capacity (IC)
Func"#al Residual Capacity (FRC)
Total air volume
+

inspire after normal
expiration ( TV+IRV)
Total air volume
+

exspire after normal
inspiration ( TV+ERV)
Expirat!y Capacity (EC)
remaining in
"
after normal expiration.
( ERV+RV )
Vital Capacity (VC)
maximum air
+

breathe in after
forced expiration.
ERV
maximum air
+

breathe our after
forced inspiration.
IRV
[ERV + TV + IRV ]
Total air volume accommodated
"

after forced inspiration.
Total Lung Capacity (TLC)
[RV+ ERV + TV + IRV or VC + RV]
pressure gradient.
concentration gradient.
Solubility of gases
thickness of membranes
Exchange of Gases
primary sites
Alveoli
B/w O2 & CO2
by
simple diffusion
Rate of di!usion
blood
,
tissues
individual gas (mixture of gases)
Par!al pre"ure
pO2 (oxygen)
pCO2 (carbon dioxide)
Table 17.1 Partial Pressures (in mm Hg) of Oxygen and Carbon dioxide at
Different Parts Involved in Diffusion in Comparison to those in Atmosphere
CO2 solubility 20-25 times > O2
CO2 gradient
tissues to blood ,
blood
,
to alveoli.
Concentration gradient
O2 gradient
alveoli to blood
,

blood
,
to tissues
Solubility of gases
CO2 amount > O2

diffusion membrane per unit difference in partial pressure Figure 17.3 Diagrammatic representation of exchange of gases at the alveolus and
the body tissues with blood and transport of oxygen and carbon dioxide
Total thickness < millimetre.
All body factors favourable for diffusion
02
alveoli to
tissues
CO2
tissues to
alveoli.
Thin squamous epithelium of alveoli
Endothelium of alveolar capillaries
Basement substance b/w them.
Di!usion membrane 3 layers
Figure 17.4 A Diagram of a section of an alveolus with a
pulmonary capillary.
A
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8. Transport of Gases
97 % by RBCs
3 % by plasma.
20-25 % by RBCs
70 % as bicarbonate.
7 % by plasma
Blood
,
Transport medium
O2
CO2
CO2O2
Transport of Oxygen
hydrogen ion concentration
Haemoglobin O2
oxyhemoglobin
Binding
1 haemoglobin 4 O2.
red ir#
partial pressure of O2
Partial pressure of CO2
temperature
O2 with haemoglobin
interfere with binding
A sigmoid curve is obtained when percentage saturation of haemoglobin with O is
plotted against the pO2. This curve is called the Oxygen dissociation curve (Figure 17.5)
highly useful in studying - pCO2, H+ concentration, etc
low pO2, high pCO2,
high H+ concentration
higher temperature
Every 100 ml of oxygenated blood
,
deliver around 5 ml of O2 to tissues
under normal physiological conditions.
Alveoli Ti"ues
oxyhemoglobin
formation
oxyhemoglobin
dissociation
high pO2, low pCO2,
lesser H+ concentration,
lower temperature
Transport of Carbon dioxide
Carbamino-haemoglobin (about 20-25 %)
binding depends upon
pCO2
pO2
low pO2, high pCO2
Alveoli
Ti"ues
Caramino-haemoglobin
formation
Caramino-haemoglobin
dissociation
high pO2, low pCO2
Carbonic
anhydrase
very high conc. RBCs
minute quantities plasma
CO2 as bicarbonate.
pCO2 high (catabolism)
CO2 diffuses into blood
,

pCO2 low
opposite direction
forms CO2 & H2O.
RBCs +
plasma
forms HCO3- & H+
Ti"ue site Alveolar site
as CO2
transported
released out
Every 100 ml of deoxygenated blood delivers 4 ml of CO2 to alveoli.
Ti"ue site
Alveolar site
Regulation of Respiration
Respiratory rhythm centres
(Inspiratory & Expiratory
centres)
Regulates normal inspiration
&expiration
Medulla
oblongata
Respiratory centresLocation Functions
Pneumotaxic
centre
Pons
alter respiratory rate by reduces
inspiration duration
Chemosensitive
area
Adjacent to
rhythm centre
Moderates respiratory rhythm centre.
Increase conc.
CO2 & H+
activate this centre
Receptors
[aortic arch & carotid artery]
signals to
rhythm centre
remedial actions
Oxygen role in regulation of respiratory rhythm is quite insignificant.
Respiratory rhythm centres
(Inspiratory & Expiratory
centres)
Regulates normal inspiration
&expiration
Medulla
oblongata
Respiratory centresLocation Functions
Pneumotaxic
centre
Pons
alter respiratory rate by reduces
inspiration duration
Chemosensitive
area
Adjacent to
rhythm centre
Moderates respiratory rhythm centre.
Increase conc.
CO2 & H+
activate this centre
Receptors
[aortic arch & carotid artery]
signals to
rhythm centre
remedial actions
Oxygen role in regulation of respiratory rhythm is quite insignificant.
Disorders of Respiratory System
inflammation of bronchi & bronchioles
breathing
.
difficulty causing wheezing
alveolar walls damaged
respiratory surface is decreased.
Asthma
Emphysema
cigarette smoking.
chronic disorder

SilICosIS
Occupational respiratory disorders
long exposure of fumes or dust.
Due to breathing of silica.
AsBesTOsiS
Due to breathing in asbestos particle
Precaution
wear protective masks.
Industries
(grinding or stone-breaking)
inflammation fibrosis (proliferation of fibrous tissues)
serious lung damage
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9. Body Fluids and Circulation
1. Blood
2. Lymph (Tissue Fluid)
3. Circulatory Pathways
4. Double Circulation
5. Regulation of Cardiac
Activity
6. Disorders of Circulatory
System
All living cells
Need nutrients, O2 , etc
waste or harmful removed continuously
But How?
Different transport methods for Different animals
Simple organisms eg. sponges & coelenterates water by body cavities
complex organisms eg. Human
!
by Blood
"
,lymph,
Blood "
special connective tissue
fluid matrix,
plasma,
formed elements.Plasma
straw coloured
viscous fluid
55 % of blood.
Fibrinogen
globulins
albumins
clotting or coagulation of blood.
defense mechanisms
osmotic balance
3 major proteins
Na+ Ca + Mg + HCO 3 - , Cl - etc.
small amnt. of minerals
always transits in body
Inactive form
90-92 % water
6-8 per % proteins
Plasma - clotting factors = serum.
Glucose, amino acids, lipids, etc.
FORMED ELEMENTS
Erythrocytes,
leucocytes
platelets
45 % of blood
leucocytes
transport of respiratory gases.
average life
span of 120 days after which they are
destroyed in the spleen (graveyard of
RBCs).
most abundant cells in blood
"

healthy
!
5 to 5.5 millions mm-3
formed in adults red bone marrow.
devoid of nucleus biconcave shape.
red coloured
iron protein (haemoglobin)
healthy
!
12-16 gms haemoglobin / 100 ml
of blood.
life span of 120 days
spleen (graveyard of RBCs)
role in transport of respiratory
gases.
Ery!rocytes or red blood cells (RBC)
Leucocytes
white blood
cells (WBC)
colourless no haemoglobin
nucleated
6000-8000 mm-3 of blood.
short lived.
Granulocytes
Neutrophils
most abundant cells
(60-65 %) of total WBCs
eosinophils
(2-3 %)
resist infections
allergic reactions
Basophils
secrete histamine,
serotonin, heparin,
inflammatory reactions.
least (0.5-1 %)
phagocytic cells
1,500,00-3,500,00 platelets mm-3
Platelets
Thr!bocytes
coagulation or clotting of blood.
If number reduction
clotting disorders
blood
"
loss
b"e ma#ow
Platelets
lymphocytes
Agranulocytes
(20-25 %)
Both B, T lymphocytes
(immune responses)
(6-8 %)
phagocytic cells
monocytes
Blood Groups
2 groupings
ABO
Rh
ABO gr$ping
based on presence or absence A & B antigens on RBC surface
induce immune response
plasma of different individuals two natural antibodies
(proteins produced in response to antigens).
During blood transfusion
If not match { clumping RBC destruction }
Table 18.1 Blood Groups and Donor Compatibility
'O' group
'universal donors'.
'AB''
universal recipients'
Rh grouping
Rh antigen Rhesus monkeys
similar
80 % humans
Avoided by administering
anti-Rh antibodies to mother immediately after
delivery of first child.
erythroblastosis foetalis.
severe anemia
& jaundice
fatal
Coagulation of BloodCalcium ions
Lymph (Tissue Fluid)
colourless fluid in lymphatic system
lymphocytes (immune responses )
carrier for nutrients, hormones, etc.
Fats absorbed by lacteals in intestinal villi
Functions
Circulatory Pathways
2 types - open or closed
eg. arthropods, molluscs
#
Annelids & chordates
open spaces or body
cavities called sinuses
closed network of
blood vessels
more advantageous
All vertebrates possess muscular chambered heart.
Amphibians, reptiles
$%

except crocodiles
&

crocodiles
&

birds
'
mammals
One Atrium
One ventricle
Single circulation
Two Atria
One ventricle
Incomplete Double
circulation (mixed)
Two Atrium
Two ventricle
Double circulation
Separated
Gill capillaries
Body capillaries
2 CHAMBERED HEART3 CHAMBERED HEART4 CHAMBERED HEART
gills/lungs/skin
Body capillariesBody capillaries
Fish
()
Heart
❤
Deoxygenated blood Oxygenated by gills.

gills /
+
/skin
oxy blood
transported to body
parts
gets deoxygenatedHeart
❤

other body parts
deoxy blood
left Atrium
Right Atrium
Mixed up in
single ventricle
Mixed Blood
"

Amphibians, reptiles
$%
except crocodiles
&

Fish ()
Incomplete Double circulation (mixed)

+
oxy blood
other body parts
deoxy blood
left Atrium
Right Atrium
No Mixed Blood
"

crocodiles
&
birds
'
mammals
Left ventricle
Right ventricle
Double circulation Separated
muscular chambered heart,
network of closed branching blood vessels
blood, circulated fluid
Human circulatory/ blood vascular system
♥
mesodermally derived organ
thoracic cavity
b/w 2 lungs
slightly left.
♥
clenched fist size
Heart
Thick
♥3 SEPTUM
Inter-Atrial Septum
Inter-Ventricular Septum
Atrio-Ventricular Septum
thin muscular wall
Thick fibrous tissues
thick wall
Prevents any backflow of blood
(unidirectional)
bicuspid
♥
valves
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10. ♥
cardiac muscles
ventricles walls thicker than atria
mass of tissue
(right atrium)
right upper corner
sino-atrial node
(SAN)
Left lower corner
atrio-ventricular
node (AVN)
bundle of nodal fibres
atrio-ventricular septa
atrio-ventricular bundle (AV
bundle)
top of inter-ventricular septum
right and left bundle
divides
purkinje fibres.
ventricular musculature
♥
normally beats 70-75 times in min (average 72 beats min-1)
Autoexcitable
pacemaker
SAN
70-75 min
initiates& maintain rhythmic contractile activity
♥
Cardiac Cycle
1 cycle = 0.8 seconds
systolic& diastole -> of {auricles & ventricles}
72 times/min
ALL 4 CHAMBERS
Relaxed state (Joint Diastole]
bicuspids
TriCuspids
Pulmonary veinsLeft AtriaLeft Ventricles
Vena Cava Right AtriaRight Ventricles
Semilunar
Valves
Closed
SAN
Action Potential
increases blood flow
"

into ventricles 30 %
Atrial systoleventricular systole
AVN & AV bundle
Action Potential
entire ventricular
musculature
atria relaxation (diastole)
coinciding with ventricular systole
increases ventricular pressure
closure of tricuspid & bicuspid valves
backflow of blood into atria.
As ventricular pressure increases,
semilunar valves open,
blood in ventricles to flow
vessels into circulatory pathways.
ventricles now relax (ventricular diastole)
ventricular pressure falls
closure of semilunar valves
prevents backflow of blood into ventricles
. ventricular pressure declines further,
tricuspid & bicuspid valves open
by atria pressure
exerted by blood
"
emptied into them by veins.
blood
"
once again moves freely to ventricles.
ventricles & atria again relaxed (joint diastole)
Soon SAN generates
new action potential
events repeated continues.
Electrocardiograph (ECG)
graphical representation of electrical activity
♥
during a cardiac cycle.
patient machine 3 electrical leads
monitor
♥
activity
one to each wrist
& left ankle
For detailed evaluation of
❤
function,
multiple leads to chest region
Figure 18.3 Diagrammatic presentation of a standard ECG
number of QRS complexes can determine
♥
individual beat rate.
ECGs different individuals same shape
If shape deviation
abnormality or disease.
Double Circulation
Two circulatory pathways, pulmonary and systemic
Right ventricle
(deoxygenated blood)
Pulmonary artery
Lungs
(oxygenated blood)
Pulmonary vein
Left atrium
Left ventricle
(oxygenated blood).
Aorta
Tissues
(deoxygenated blood)
veins
Right atrium
Pulmonary Systemic
blood flows by Blood Vessels { arteries and veins }
inner lining of squamous endothelium, tunica intima,
middle layer of smooth muscle and elastic fibres, tunica media,
external layer of fibrous connective tissue with collagen fibres, tunica externa.
each artery & vein
thin3 layers
Figure 18.4 Schematic plan of blood circulation in human
Regulation of Cardiac Activity
intrinsically
muscles (nodal tissue), myogenic
♥

Normal activities
autonomic nervous system
(ANS).
sympathetic
parasympathetic
❤
beat rate
ventricular contraction
cardiac output.
medulla
oblangata
increases
decreases
❤
beat rate
Action potential
cardiac output.
Adrenal medullary hormones also increase cardiac output.
Cardiac
function
Disorders of Circulatory System
High Bl!d Pre"ure (Hypertension)
blood pressure higher than normal (120/80).
120 mm Hg systolic, or pumping pressure
80 mm Hg diastolic, or resting pressure.
140/90 or higher,
(millimetres of
mercury pressure)
repeated checks bp
hypertension
heart diseases
affects brain & kidney.
Coronary Artery Disease (CAD)
affects blood vessels of
❤
muscle.
by deposits of calcium, fat, cholesterol and fibrous tissues,
lumen of arteries
narrower.
men and women of any age
Angina
'angina pectoris'.
Affect blood flow
acute chest pain
no enough O2
♥
muscle
more common among middle-aged & elderly.
heARt aTtACk
Heart Failure
not pumping enough blood
"

main symptoms
lungs congestion
+
heart
♥
stops beating
HeArT faILurE
caRdIaC ArResT ❤
muscle suddenly damaged by
inadequate blood
"
supply
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11. Excretory Products and their Elimination
19.1 Human Excretory System
19.2 Urine Formation
19.3 Function of the Tubules
19.4 Mechanism of Concentration of the Filtrate
19.5 Regulation of Kidney Function
19.6 Micturition
19.7 Role of other Organs in Excretion
metabolic ac!vi!es " #ce$ inges!%.
Ammonia,
urea,
uric acid,
carbon dioxide,
water
!

ions like Na+, K+, CI-,phosphate,sulphate
Animals a!umulates
Removed totally or partially.
major forms of
nitrogenous wastes
By
most toxic & requires
more water
least toxic,
Less water
TYPES OF EXCRETION
Many bony fishes,
aquatic amphibians,
aquatic insects
Mammals,
many terrestrial
amphibians
marine fishes
Reptiles, birds,
land snails
"

insects
Ammonotelic
ureotelicuricotelic
pellet or paste
Kidneys no significant role in its removal.
Ammonium ions
By diffusion
Readily soluble
body surfaces " gill surfaces (in fish)
ureotelic Animals
Ammonotelic Animals
by
metabolism
converted into urea
By liver
released into blood
#

A"onia
filtered &
excreted outby kidneys
Some urea retained in
kidney matrix for
osmolarity
Then
Most invertebrates
simple tubular forms
vertebrates
complex tubular organs
Eg. kidneys.
Protonephridia
(Flame ce#s)
Nephridia
Malpighian tubules
Ante$al glands (gr%n glands)
Platyhelminthes (Flatworms, e.g.Planaria),
rotifers
some annelids & cephalochordate
(Amphioxus)
Excretory structures Examples
earthworms & other annelids
most insects including cockroaches
crustaceans like prawns
Human Excretory System
1 pair of kidneys,
1 pair of ureters,
a urinary bladder
a urethra
reddish brown,
bean shaped
Kidneys
situated b\w levels of last thoracic
& 3rd lumbar vertebra
Each kidney
adult human
10-12 cm length,
5-7 cm width,
2-3 cm thickness
120-170 g. weight
close to dorsal inner wall of abdominal cavity
inner concave surface of kidney
ureter,
blood
#
vessels
nerves enter
broad funnel shaped
with projections( calyces)
tough capsule
outer cortex
inner medulla.
Columns of Bertini
Each kidney
1 million complex tubular structures { nephrons }
Each nephron
2 parts { glomerulus & renal tubule }
functional units
tuft of capillaries
Glomerulus renal tubule
#
away
#
Comes
malpighian body or
renal corpuscle
hairpin
shaped
open into renal pelvis
Malpighian corpuscle, PCT
and DCT of nephron
loop of Henle dips
Kidney cortical regionKidney medulla region
cortical nephronsjuxta medu#ary nephrons
majority of nephrons
loop of Henle too short
very little into medulla.
loop of Henle very long
runs deep into medulla.
fine capillary network
around renal tubule
network runs parallel to
Henle's loop
U' shaped
absent or highly reduced
in cortical nephrons
Urine Formation
glomerular filtration,
reabsorption
secretion,
different parts of nephron.
3 main processes
blood
#
1100-1200 ml / min
1st step
glomerulus
{ glomerular filtration}
by kidneys
filtered
1/5th of
blood pumped out by
each ventricle of heart
♥
1minute
Endothelium of glomerular blood vessels
Epithelium of Bowman's capsule.
Basement membrane b/w these 2 layers.
bl&d #filtration through 3 layers
intricate
manner
ultra filtration
almost all constituents of plasma except proteins pass
onto lumen of Bowman's capsule.
99 % reabs"bed by renal tubules.
urine released (1.5 litres)
amount of filtrate / min
Glomerular filtration rate (GFR).
healthy individual approx 125 ml/minute,
i.e., formed 180 litres / day
tubular epithelial cells in different segments of nephron
Active
glucose, amino acids,
Na+ etc
nitrogenous wastes
Passive
water
!
{nephron initial segments }
tubular cells secrete substances like H+, K+ & ammonia into filtrate.
helps in maintenance of ionic & acid base balance of body fluids.
Imp"tant step in urine &rma!%
Function of the Tubules
Proximal Convoluted Tubule (PCT)
cuboidal brush border
epithelium
increases surface
area for reabsorption
Nearly all essential nutrients,
70-80 % of electrolytes & water
by selective secretion of
hydrogen ions, ammonia
and potassium ions into
filtrate
maintain pH and ionic balance
by absorption
of HCO3- from it.
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12. Henle's L&p
Ascending limb.
High osmolarity of
medullary interstitial fluid.
Reabsorption minimum
Descending limb
water
%
permeable
electrolytes impermeable
conc. filtrate
moves down
water
%
impermeable
electrolytes permeable
actively or
passively
conc. filtrate
moves upward
Reabsorption of HCO3-
Distal Convoluted Tubule (CT)
Conditional reabsorption of Na+ & water
%

selective secretion of hydrogen, potassium ions & NH3
to maintain pH & sodium-potassium balance in blood.
Figure 19.5 Reabsorption and secretion of major substances at different parts of
the nephron (Arrows indicate direction of movement of materials.)
Allows passage of small amounts of urea into medullary interstitium for osmolarity.
maintain of pH & ionic balance of blood
#

by selective secretion of H+ & K+ ions
Collecting Duct
Large amounts of water
reabsorbed produce conc.
urine.
Mechanism of Concentration of the Filtrate
Mammals produce a concentrated urine
By Henle's loop & vasa recta
filtrate flow
2 limbs of Henle's l&p
opposite directions
{ counter current }
blood
#
flow
2 limbs of vasa recta
also counter current
proximity b/w Henle's l&p & vasa recta + counter current
i.e. from 300 mOsmolL-1 in cortex to 1200 mOsmolL-1 in inner medulla.
maintain osmolarity towards
inner medullary interstitium
This gradient by NaCl & urea
Ascending limb of Henle's l'p
NaCl
Descending limb of vasa recta
Back to interstitium
Ascending p"!% of vasa recta.
collec!ng tubule
small amounts of urea
Ascending limb of Henle's l'p
Back to interstitium
water easy passage from collecting tubule
Human kidneys { urine} 4 times conc, than initial filtrate formed.
Figure 19.6 Diagrammatic representation of a nephron and vasa recta showing counter current mechanisms
conc. filtrate (urine)helps to maintain conc. gradient in medullary interstitium.
Regulation of Kidney Function
kidneys functions monitored & regulated by hormonal feedback mechanisms
hypothalamus, JGA & to certain extent, heart.
Osmoreceptors
activated by
changes in
blood
#
volume,
body fluid volume
ionic concentration
excessive loss of body fluid osmoreceptors
stimulate hypothalamus
release
antidiuretic hormone (ADH) or
vasopre'in
from neurohypophysis.
activate
ADH
preventing
diuresis
By water reabsorption
from tubule latter parts
affect kidney function by its
constrictory effects on blood
vessels
increase in blood
pressure
increase glomerular blood flow
and thereby GFR
To complete feedback
If body fluid volume increase
switch off
osmoreceptors
suppress
ADH release
Inbuilt Regulation of glomerular filtration rate
juxta glomerular apparatus (JGA)
fall in GFR. JG cells
renin
activate
stimulate glomerular blood
flow
GFR back to
normal.
special sensitive region
release
Renin-
Angiotensin
increases glomerular
blood pressure&
thereby GFR.
By Atria increase blood flow
♥

Atrial Natriuretic Factor (ANF)
vasodilation
So decrease blood
#
pressure.
check on renin-angiotensin
mechanism
Micturition
Adult human 1 to 1.5 litres of urine / day.
process of urine release
By neural mechanisms { micturition reflex }
till voluntary signal by
central nervous system (CNS)
nephrons
Urine formed
urinary bladder
Urine stored
filled with
urine.
initiated by urinary
bladder stretching
motor messages
initiate contraction of
bladder smooth muscles
simultaneous
relaxation of
urethral sphincter
releases of urine
light yellow coloured watery fluid
urine
slightly acidic (pH-6.0) & has odour.
25-30 gm urea is excreted out / day.

clinical diagnosis of many metabolic disorders & kidney malfunctioning
Urine Analysis
presence of glucose (Glycosuria)
ketone bodies (Ketonuria)
Example Diabetes mellitus
Role of other Organs in Excretion
kidneys
lungs
&

liver
skin
Our lungs
&

remove large amounts of CO2 (approx 200mL/min)
also significant quantities of water every day.
largest gland
secretes bile-containing substances
Liver
bilirubin, biliverdin,
cholesterol,
degraded steroid
hormones, vitamins, drugs
Most pass out along with
digestive wastes.
Skin
Also remove
NaCl, small amounts of
urea, lactic acid, etc.primary function
cooling effect on
body surface,
eliminate
sterols, hydrocarbons
& waxes
protective
oily covering for skin.
sebum
Sweat
'

Do you know that small amounts of nitrogenous wastes could be eliminated through saliva too?
Disorders of the Excretory System
uremia
accumulation of urea in blood,kidneys Malfunctioning
In such patients, hemodialysis.
artificial kidney.
after adding
anticoagulant (heparin )
after adding anti-heparin
coiled cellophane tube
This method is boon for thousands of uremic patients all over world.
Kidney transplantation
For acute renal failures (kidney failure)
From close relative
Renal calculi
Stone or insoluble mass of crystallised
salts (oxalates, etc.)
formed within kidney.
Glomerulonephritis
Inflammation of glomeruli of kidney
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13. Locomotion and Movement
1. Types of Movement
2. Muscle
3. Skeletal System
4. Joints
5. Disorders of Muscular and Skeletal
System
Animals & plants
!
Movement
features of living beings.
diff types of movements.
unicellular organisms
like Amoeba
Streaming of protoplasm
Movement by
many organisms cilia, flagella ,tentacles
Movement by
Human beings limbs, jaws, eyelids,
tongue, etc.
Movement by
all locomotions are movements
but all movements are not locomotions.
Eg Walking
"
running
#
climbing
$
flying
✈
swimming
&
Locomotion
Some voluntary
movements.
change
place or location.
Eg. Paramecium, cilia
Same structure for both locomotion & movement
changes in body postures
locomotion
food movement
locomotion
( cytopharynx )
Hydra
( tentacles )
prey capturing
locomotion.
Human beings
( limbs )
generally locomotion
Methods of locomotion
performed by animals vary with their habitats & situation demand
for search of food,
shelter, mate, suitable breeding grounds,
favourable climatic conditions or
to escape from enemies/predators
Types of Movement
human body cells
3 main types of movements,
amoeboid,
ciliary
muscular.
macrophages & leucocytes in blood
'

Cytoskeletal (microfilaments)
Ameboid movement
internal tubular organs lined by ciliated epithelium.
Ciliary movement
cilia movements in trachea
remove dust particles
&some foreign substances
ciliary movement in female reproductive tract
Passage of ova
majority multicellular organisms.
Locomotion requires
muscular movement
our limbs, jaws, tongue, etc,
human beings
contractile property of muscles
perfect coordinated activity of muscular + skeletal + neural systems.
Muscle
specialised tissue of mesodermal origin.
About 40-50 % of body weight (human adult)
Muscles classified
using location,
appearance,
nature of regulation activities
excitability,
contractility,
extensibility
elasticity.
Based on location, 3 types of muscles
1) Skeletal
2) Visceral
3) Cardiac.
locomotory actions &
body postures changes
transportation of food & gametes
By digestive tract & genital tract.
skeletal muscle structure
store house of calcium ions.

Figure 20.2 Diagrammatic representation of (a) anatomy of a muscle fibre showing
a sarcomere (b) a sarcomere
Structure of Contractile Proteins
Each actin (thin) filament
helically wound to each other
monomeric 'G' (Globular) actins
2 two 'F' (filamentous) actins
regular intervals
resting state ,troponin masks active binding sites for myosin on actin filaments
Myosin monomer (Meromyosin)
Each myosin (thick) filament also polymerised protein.
Each meromyosin 2 parts, a globular head with short arm and tail,
active ATPase enzyme
Mechanism of Muscle Contraction
sliding filament theory
thin filaments over thick filaments.
Muscle contraction
central nervous system
(CNS)
via motor neuron
signal
motor neuron + muscle fibres
motor unit
generates action
potential in
sarcolemma.
Figure 20.4 Stages in cross bridge formation, rotation of head & breaking of cross bridge
Figure 20.5 Sliding-filament theory of muscle contraction (movement of the thin
filaments and the relative size of the I band & H zones)
Myoglobin high Myoglobin low
More mitochondria
More oxygen
More ATP production.
Aerobic muscles.
Anaerobic muscles.
Less mitochondria
No oxygen
High sarcoplasmic reticulum
pale or whitish.
White fibresRed fibres
Red
Skeletal System
framework of bones & few cartilages.
very hard matrix
due to calcium salts
pliable matrix
due to chondroitin salts.
206 bones few cartilages.
It is grouped into 2 principal divisions
Axial &
Appendicular skeleton.
Axial skeleton
80 bones distributed along body main axis
skull, vertebral column, sternum and ribs
8 Cranial bones
totals 22 bones
sku!
hard protective
outer covering,
cranium for brain.
14 facial bone
front part of skull.
U-shaped bone
base of buccal cavity
skull region articulates with superior region of vertebral column
by two occipital condyles (dicondylic skull).
vertebral column
formed by 26 serially arranged units dorsally placed.
Extends frm base of skull
(

constitutes trunk main framework
Each vertebra
spinal cord passes.
central hollow portion (neural canal)
First vertebra
Atlas and articulates with
occipital condyles.
cervical (7),
thoracic (12),
lumbar (5),
sacral (1-fused)
coccygeal (1-fused)
vertebral column
almost In all mammals
protects spinal cord,
supports head
attachment for ribs &
musculature of back.
Sternum flat bone on
ventral midline of thorax.
12 pairs of ribs.
Ribs
do not articulate directly
with sternum but join 7th rib
by hyaline cartilage.
vertebrochondral
attached to thoracic vertebrae
& ventrally connected to
sternum by hyaline cartilage
Thoracic vertebrae,
+ ribs + sternum
not connected ventrally
Rib cage
Appendicular skeleton.
limbs bones + girdles
Each limb 30 bones
carpals (wrist bones - 8),
metacarpals (palm bones - 5)
phalanges (digits 14)
fore limbhand bones
humerus, radius, ulna
Figure 20.9 Right pectoral girdle and upper arm. (frontal view)
tarsals (ankle bones (7)
metatarsals (5)
phalanges (digits 14)
legs
)
bone
cup shaped bone
ventrally (knee cap).
hind limb
Femur (thigh longest bone), tibia and fibula,
Figure 20.10 Right pelvic girdle and lower limb bones (frontal view)
↓
V
V
7↓
↓
7
-
7
II
-
V
V V
↓ ↓
W ↓↓
-
↓
r
-
7
>

14. helps in upper & lower limbs articulation with axial skeleton.
Pectoral & Pelvic girdle bones
Pectoral girdle bones
slightly elevated ridge (spine)
flat,
Scapula
large triangular flat bone
dorsally thorax b/w 2nd & 7th ribs.
Each clavicle
long slender bone with
two curvatures.
clavicle articulates
with acromion
glenoid cavity
humerus head
shoulder joint.
clavicle
Collar bone
Scapula
Collar bone
Joints
essential for all types of movements (bony body parts also)
contact b/w bones, or b/w bones & cartilages.
muscles Force to carry out movement through joints,
.
joint acts as fulcrum
fibrous,
cartilaginous
synovial.
3 major joints
2 pelvic girdle halves meet ventrally pubic symphysis (fibrous cartilage)
Pelvic girdle
2 coxal bones
Each coxal bone. 3 bones ( ilium, ischium , pubis) .
do not allow any movement.
Eg. flat skull bones
Fibrous joints
fuse end-to-end
cranium
Cartilaginous joints
permits limited movements
bones joined by cartilages
Synovial joints
help in locomotion & many other movements
fluid filled synovial cavity b/w 2 bones
Ball & socket joint (b/w humerus & pectoral girdle),
hinge joint (knee joint),
pivot joint (b/w atlas & axis),
gliding joint (b/w the carpals)
saddle joint (b/w carpal & metacarpal of thumb)
Some examples of Synovial joints
Disorders of Muscular and Skeletal System
Myasthenia gravis
Auto immune disorder affecting neuromuscular junction
fatigue,
weakening
paralysis of skeletal muscle.
Progressive degeneration of skeletal muscle mostly due to genetic disorder.
Muscular dystrophy
Rapid spasms (wild contractions) in muscle due to low Ca++ in body fluid.
Tetany
Inflammation of joints.
Arthritis
Age-related disorder
decreased bone mass & increased chances of fractures.
Decreased levels of estrogen
Osteoporosis
Inflammation of joints due to accumulation of uric acid crystals.
Gout
↓
At
>
a
7
v

15. Neural Control and Coordination
1. Neural System
2. Human Neural System
3. Neuron as Structural and
Functional Unit of Neural System
4. Central Neural System
5. Reflex Action and Reflex Arc
6. Sensory Reception and Processing
Functions of organs/
organ systems

maintain
homeostasis.
coordinated
Coordination
2 or more organs interact/ complement functions
energy demand
oxygen
physical exercises
respiration rate
heart
♥
beat
blood flow
increased
physical exercises stop
✋

activities of nerves,
lungs,
heart
kidney
normal conditions.
neural system + endocrine system = coordinate , integrate all organs activities.
synchronised fashion
Neural System
All animals neurons
detect, receive
transmit
different stimuli.
Neural organisation
Hydra
network of neurons
insects brain
#
+no.of ganglia + neural tissues.
vertebrates
more developed neural system
Human Neural System
1) central neural system (CNS)
2) peripheral neural system (PNS)
2 parts
site of information processing, control.
CNS
brain + spinal cord
All body nerves associated with CNS
PNS
Nerve fibres 2 types
(a) afferent fibres
(b) efferent fibres
SNS
ANS
VNS
tissues/organs to CNS CNS to tissues/organs.
efferent nerve fibresAfferent nerve fibres
somatic neural system
autonomic neural system.
sympathetic neural system and
parasympathetic neural system.
Visceral nervous system
impulses from CNS to skeletal muscles
CNS to involuntary organs &smooth muscles
whole complex of nerves + fibres +
ganglia, + plexuses

from CNS to viscera
from viscera to CNS
PNS
Neuron as Structural and Functional Unit of Neural System
neuron
microscopic structure
3 major parts
cell body , dendrites, axon
cytoplasm + typical cell organelles +
certain granular bodies {Nissl's granules}
cell body
Short fibres branch + Nissl's granules
transmit impulses towards cell body.
repeatedly & project out of cell body
dendrites
axon
long fibre
distal end branched
bulb-like structure
synaptic vesicles
neurotransmitters
cell body to synapse or neuro-muscular junction.
2 types of axons
3 types of neurons
eye retina $

cerebral cortex
embryonic stage
1 axon & 1 dendrite
1 axon & 2 or more dendrites
Only axon
Generation and Conduction of Nerve Impulse
selectively permeable
concentration gradient.
Figure 21.2 Diagrammatic representation of impulse conduction through an axon (at points A & B)
Transmission of Impulses
one neuron another neuron
junctions
{ synapses }
nerve impulse
To
By
2 types synapses,
electrical synapses & chemical synapses.
always faster
rare in our system.
specific receptors
new potential developed either
excitatory or inhibitory
Central Neural System
central information processing body organ
acts as 'command and control system'.
brain
voluntary movements,
Body balance
functioning of vital involuntary organs
e.g., lungs, heart, kidneys, etc.
thermoregulation,
hunger & thirst,
circadian (24-hour) rhythms
several endocrine glands activities
human behaviour.
controls
site for processing of vision, hearing, speech, memory, intelligence,
emotions & thoughts.
#
protected by skull.
Inside skull,
#
covered by cranial meninges
outer layer {dura mater }
thin middle layer {arachnoid}
inner layer (contact with tissue){pia mater }
Figure 21.4 Diagram showing sagital section of the human brain
#divided into 3 major parts
1. forebrain,
2. midbrain,
3. hindbrain
Forebrain
cerebrum,
thalamus ,
hypothalamus
major part
cerebrum
hemispheres
connected
nerve fibres
corpus callosum.
left cerebral
hemispheres.
right cerebral
hemispheres.
longitudinally deep cleft
prominent folds.
covered with myelin sheath,
motor areas,
sensory areas
association areas
3 areas of cerebral cortex
intersensory associations,
memory
communication.
thalamus
major coordinating centre for sensory & motor signaling.
cerebrum wraps around thalamus,
hypothalamus
hypothalamus centres
neurosecretory cells (hypothalamic hormones)
control body temperature
%

urge for eating
&
& drinking
'

regulation of sexual behaviour,
expression of emotional reactions
(e.g., excitement,pleasure, rage
and fear),
motivation.
Midbrain
located between
forebrain
thalamus/hypothalamus
hindbrain
pons
canal
four round swellings
(lobes)
Hindbrain
pons, cerebellum, medulla
fibre tracts
interconnect different
brain regions.
very convoluted surface
provide additional space for
many more neurons.
connected to spinal cord.
control respiration,
cardiovascular reflexes
gastric secretions.
forms connections
B/w brain & spinal cord.
Reflex Action and Reflex Arc
without conscious effort or thought
& requires CNS
stimulus & response forms
reflex arc
peripheral nervous stimulation
extremely hot
(

cold pointed
)

animal
*

+
scary or poisonous
,

sudden withdrawal body part
7
%
M
L
7
i
S
-
7
1
7 I
S
I
7
S
V
↓
v
-1
·
W
7
~
v
1
-
↓
.
xA
V
m
*
↓ ↓

16. Figure 21.5 to understand the mechanism of a knee jerk reflex.
Sensory Reception and Processing
sensory organs detect all types environment changes, sound , colors, taste
signals to CNS
Sense Organs
smell by our nose
-

taste by tongue
.

hear by ear
/

see objects by eyes
0

Both nose and tongue detect dissolved chemicals.
functionally similar & interrelated.
olfactory
(smell)
gustation
(taste)
Eye $
orbits sockets Eyes
0

Parts of an eye
Adult human eye ball spherical structure.
Adult human eye ball 3 layers
external layer dense connective tissue.
1) sclera layer
( anterior portion )cornea
2) choroid layer
middle layer many blood vessels, looks bluish colour.
thin posterior 2/3 of eye ball,
thick anterior part [ ciliary body ]
visible coloured portion
transparent crystalline lens
ligaments
pupil diameter
regulated by iris
muscle fibres
3 layers of neural cells - from inside to outside
ganglion cells,
bipolar cells
photoreceptor cells.
3) Retina inner layer
rods & cones.
rods.cones
daylight (photopic) color vision
twilight (scotopic) vision
purplish-red protein
rhodopsin or visual purple,
contain {Vitamin A derivative}
3 cones types
photopigments
red, green, blue lights.
diff colours sensations by
various combinations of 3 cones
& its photopigments.
3 cones stimulated equally,
white light sensation produced.
No Photoreceptor cells
Retina thinned-out portion
only cones densely packed.
yellowish pigmented spot
central pit
greatest visual acuity
(resolution).
space between cornea & lens
aqueous chamber
aqueous humor
contains thin watery fluid
space between lens & Retina
vitreous chamber
vitreous humor
transparent gel
Mechanism of Vision
photosensitive compounds (photopigments)

opsin
(protein)
retinal
(aldehyde of vitamin A).
action potentials
impulses analysed
Retina image recognised
based on earlier memory and
experience.
Ear
hearing
body balance maintenance .
2 sensory functions
Anatomically, ear into 3 major sections
pinna
ear drum
meatus
outside connective tissues covered with skin
& inside with mucus membrane.
3 ossicles (malleus, incus , stapes) chain-like fashion.
tympanic membrane oval window of cochlea.
increase efficiency of transmission of sound waves to inner ear.
Attach
connects middle ear cavity with pharynx
middle ear
helps in equalising pressures on either sides of ear drum
pinna collects vibrations in air, produce sound.
meatus
outer ear
leads inwards, extends up to tympanic membrane
very fine hairs &
wax-secreting glands
Eustachian tube
Inner ear
Mechanism of Hearing
Sound waves received
by external auditory
meatus
eardrum vibrates
malleus, incus and
stapes amplify the
vibrations
vibration reaches
inner ear through oval
window
sound waves into neural impulses,
lymphs waves
ripple basilar membrane.
bend hair cells, pressing them
against tectorial membrane.
nerve impulses
generated in
afferent neutrons.
impulses transmitted by afferent
fibres via auditory nerves to
brain
#
auditory cortex
impulses analysed &
sound recognised
7
.
7
7
7
-
~
W
v
v
-
7
/
v
v
7 7
~
W
-

17. Chemical Coordination & Integration
1. Endocrine Glands and Hormones
2. Human Endocrine System
3. Hormones of Heart, Kidney and
Gastrointestinal Tract
4. Mechanism of Hormone Action
point-to-point rapid coordination among organs.
fast but short-lived.
nerve fibres do not innervate all body cells & cellular functions
neural system + endocrine system jointly coordinate and regulate
body physiological functions
.
neural system
endocrine system
coordination and integration by hormones.
Ductless glands.
classical definition
chemical produced by
endocrine glands & released
into blood & transported to
distantly target organ
current scientific definition
non-nutrient chemicals act as
intercellular messengers & produced in
trace amounts.
Endocrine Glands and Hormones
secretions
hormone definitions
covers new molecules + hormones
secreted
New definition
vertebrates
large number of hormones & provide coordination
Invertebrates
simple endocrine systems +few hormones
Human Endocrine System
endocrine glands & hormone
producing
diffused tissues/cells
Located in diff body parts
Pituitary, pineal, thyroid, adrenal, pancreas, parathyroid,
thymus gonads (testis ,ovary)
gastrointestinal tract, liver, kidney, heart
Hypothalamus
basal part of diencephalon, forebrain
neurosecretory cells( nuclei) produce hormones.
regulate synthesis & secretion
of pituitary hormones.
Hypothalamus 2 types Hormones
stimulate secretion of
pituitary hormones
inhibit secretions of
pituitary hormones
releasing hormonesinhibiting hormones
Gonadotrophin releasing
hormone (GnRH)
stimulates pituitary synthesis &
release of gonadotrophins.
somatostatin
inhibits growth release
hormone from pituitary.
hypothalamic neuronshormones axons
nerve endings
portal
circulatory system
pituitary gland
regulate anterior
pituitary functions
under direct neural regulation of hypothalamus
anterior pituitary
posterior pituitary
The Pituitary Gland
stalk
pars nervosa
stores & releases
oxytocin & vasopressin hormones
synthesised by hypothalamus
&transported axonally here
growth hormone (GH),
prolactin (PRL),
thyroid stimulating hormone (TSH),
adrenocorticotrophic hormone (ACTH),
luteinizing hormone (LH)
follicle stimulating hormone (FSH).
only 1 hormone
melanocyte stimulating
hormone (MSH).
Produces
secretes
growth hormone (GH)
Over-secretion
gigantismdwarfism
abnormal growth stunted growth
low secretion
severe disfigurement
Acromegaly
Excess secretion GH (adults) middle age
serious complications,
premature death if unchecked.
hard to diagnose in early stages,
often undetected for many years
until changes noticeable.
TSH
thyroid hormones
from thyroid gland.
Prolactin
regulates growth of mammary glands & formation of milk
ACTH
steroid hormones( glucocorticoids)
from adrenal cortex.
stimulates synthesis &secretion
LH & FSH stimulate gonadal activity
gonadotrophins
LH stimulates
synthesis & secretion
androgens from testis.
FSH & androgens
regulate spermatogenesis
ovulation fully graafian follicles
maintains corpus luteum,
FSH stimulates
growth & development
ovarian follicles
In femalesIn males
LH induces
acts on melanocytes (melanin containing cells)
regulates skin pigmentation
MSH
acts on body smooth muscles (s!mulates c"trac!")
In females child birth time (uterus vig#$s c"trac!")
milk ejection from mammary gland.
Oxytocin
acts on kidney {s!mulates water, electrolytes res#p!"}
anti-diuretic hormone (ADH). (No diuresis)
Vasopressin
If no ADH
Diabetes Insipidus ( water lo% and dehydra!" )
The Pineal Gland
dorsal side of forebrain
maintaining normal rhythms of sleep-wake cycle,
body temperature.
influences metabolism, pigmentation,
menstrual cycle
defense capability.
24-hour (diurnal)
body rhythm
hormone (Melatonin)
Thyroid Gland
thin flap of connective tissue
B/w 2 lobes
follicles tissue
Each thyroid gland
follicular cells
tetraiodothyronine or thyroxine (T4)
triiodothyronine (T3).
follicles
stromal tissues.
lodine For normal rate of thyroid hormone synthesis.
If iodine Deficiency (hypothyroidism)
defective development ,
stunted growth (cretinism),
mental retardation,
low intelligence quotient,
abnormal skin,
deaf-mutism, etc.
Hypothyroidism during pregnancy
!

irregular menstrual cycle .
adult women, hypothyroidism
hyperthyroidism
Due to cancer or nodules in thyroid glands,
rate of synthesis abnormal increased high levels
(affects body physiology )
Exopthalmic goitre
hyperthyroidism,
enlargement thyroid gland,
protrusion eyeballs,
increased basal metabolic rate
& weight loss,
Graves' disease.
regulation of basal metabolic rate.
red blood cell formation.
control metabolism of carbohydrates, proteins, fats.
Maintenance of water & electrolyte balance
thyrocalcitonin (TCT) regulates blood calcium levels.
Thyroid hormones
Parathyroid Gland
4 parathyroid glands
back side of thyroid gland,
parathyroid glands
regulated bysecrete by
peptide hormone (parathyroid hormone (PTH)
circulating levels of Ca+
Parathyroid h#m"e (PTH)
increases Ca2+ levels in blood.
acts on bones, (s!mulates b"e res#p!" (di%olu!"/de&neralisa!").
s!mulates reabs#p!" of Ca2+ by renal tubules
increases Ca2+ abs#p!" from digested food.
Along with TCT, calcium body balance.
↓
t
..
-
↓
-
V
V

18. Thymus gland
lobular structure b/w lungs behind sternum on ventral aorta side
major role in immune system development
secretes peptide hormones (thymosins)
differentiation of T-lymphocytes,
cell-mediated immunity.
promote production of antibodies to
provide humoral immunity.
Old Child
Adrenal Gland
anteri# part
Underproduction of hormones by adrenal cortex
alters carbohydrate metabolism
causing acute weakness & fatigue
Adrenal medulla
adrenal medulla
secretes
2 hormones
noradrenaline
(norepinephrine)
adrenaline
(epinephrine)
also stimulate breakdown of glycogen
breakdown of lipids &proteins.
increase alertness,
pupilary dilation,
piloerection (raising of hairs),
sweating
heart beat,
heart contraction
rate of respiration.
emergency hormones or hormones of Fight or Flight.
Catecholamines
cortisol main
glucocorticoid.
carbohydrate metabolism
Aldosterone main
mineralocorticoid
regulate balance of water &
electrolytes
glucocorticoid
Increases
gluconeogenesis,
lipolysis
proteolysis;
inhibit
cellular uptake
amino acids utilisation
maintaining cardio-vascular system& kidney functions.
produces anti-inflammatory reactions
suppresses immune response.
Cortisol
Pancreas
composite gland both endocrine gland & exocrine
1 to 2 million Islets of Langerhans
glucagon. insulin.
1 to 2 % of pancreatic tissue.
Alpha cells & beta cells.
pep!de h#m"es
hyperglycemic
hypoglycemia
acts on hepatocytes
stimulates glycogenolysis , gluconeogenesis
reduces cellular glucose uptake & utilisation.
Acts on hepatocytes and adipocytes
enhances cellular glucose uptake and utilisation.
also stimulates glycogenesis in target cells.
Prolonged hyperglycemia
associated with glucose loss by urine
ketone bodies formed.
diabetes mellitus
treated with
insulin therapy.
Testis
"
pair of testis in scrotal sac (outside abdomen) of male
dual functions
primary sex organ &
endocrine gland.
Testis
seminiferous
tubules
stromal or
interstitial tissue.
Location intertubular spaces
Function produce androgens mainly testosterone.
Leydig cells or interstitial cells
regulate development,
maturation & functions of male accessory sex organs
epididymis,
vas deferens,
seminal vesicles,
prostate gland,
urethra etc.
stimulate muscular growth,
growth of facial & axillary hair,
aggressiveness,
low pitch of voice etc.
spermatogenesis (formation of spermatozoa).
produce anabolic (synthetic) effects on protein &
carbohydrate metabolism
Androgens act on CNS influence
male sexual behaviour (libido).
Ovary
#
pair of ovaries located in abdomen
dual functions
primary sex organ &
endocrine gland.
Ovary
ovarian follicles. stromal tissues.
secretes mainly progesterone
estrogen
stimulation of growth & activities of female secondary sex organs,
development of growing ovarian follicles,
female secondary sex characters (e.g., high pitch of voice, etc.)
mammary gland development.
regulate female sexual behaviour.
Estrogens
supports pregnancy.
acts on mammary glands & stimulates alveoli formation
(sac-like structures which store milk) and milk secretion.
Progesterone
Hormones of Heart, Kidney, Gastrointestinal Tract
hormones. some tissues.
endocrine glandshormones
Location Peptide hormones
Function
heart
atrial wall
atrial natriuretic factor
(ANF), blood pressure decreases
blood vessels dilation
juxtaglomerular cells
kidney
erythropoietin
stimulates erythropoiesis
gastro-intestinal tract
gastrin
secretin,
cholecystokinin (CCK)
gastric inhibitory
peptide (GIP).
gastric glands
exocrine pancreas
Location Peptide hormones Function
HCL & pepsinogen
secretions
water &
bicarbonate ions
secretions
both pancreas and
gall bladder
secretion of pancreatic
enzymes , bile
juice.
inhibits gastric
secretion & motility.
Several other non-
endocrine tissues
normal growth of
tissues & their
repairing/regeneration.
Small intestine
Mechanism of Hormone Action
Hormones
target tissues
specific hormone receptors
membrane-bound
receptors
intracellular receptors,
mostly (nuclear receptors)
generate second messengers
(e.g. cyclic AMP,Ip3, Ca++ etc)
in turn regulate cellular
metabolism
(e.g., steroid hormones,
iodothyronines, etc.)
regulate gene expression or
chromosome function
Protein hormone Steroid hormone
hormones divided On basis of chemical nature
hormone + receptor = hormone-receptor complex
biochemical changes
metabolism
physiological functions regulated
peptide, polypeptide, protein hormones
steroids
iodothyronines
amino-acid derivatives
insulin, glucagon, pituitary
hormones, hypothalamic
hormones, etc.
cortisol, testosterone,
estradiol and progesterone)
thyroid hormones
epinephrine
Examples
hormones
E
I
7
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>
V
->
1
L V
7
↓
I
↓
I
>
>
Mr
7