THE-CELL PDF Biology grade 12 and grade 11

The topic all about is cells, philosophers of cells, parts of cells and functions

1. THE CELL
LESSON 1

4. PROPERTIES OF
LIFE

5. 1. ORDER
-Organismsconsistofhighly
organizedandcoordinatedstructures
madeofoneormorecells.Even
simple,single-celledorganismsare
madeupoforganellescomposedof
molecules;moleculesareinturn
madeupofatoms.Mostmulticellular
organismsarecomposedoforgan
systemsthatworktogether.Organs
aremadeupoftissuesthatconsistof
similarcells.

6. II.SENSITIVITY
OR RESPONSE
TO STIMULI
-Organismsrespondto
diversestimuli.Movement
towardastimulusis
considereda positive
response,whilemovement
awayfromastimulusis
considereda negative
response.

7. III.
REPRODUCTION
-Single-celledorganisms
reproducebyfirstduplicating
theirDNA,andthendividingit
equallyasthecellpreparesto
formtwo new cells.
Multicellularorganismsoften
produce specialized
reproductivegermlinecellsthat
giverisetogametesthatare
usedtoformnewindividuals.

8. IV. GROWTH
AND
DEVELOPME
NT
-Organismsgrowand
developfollowingspecific
instructionscodedforby
theirgenes.Thesegenes
provideinstructionsthatwill
directcellulargrowthand
development,ensuringthata
species’youngwillgrowup
toexhibitmanyofthesame
characteristicsasitsparents.

9. V.
REGULATION
-Eventhesmallest
organismsarecomplexand
requiremultipleregulatory
mechanismstocoordinate
internalfunctions,respond
tostimuli,andcopewith
environmentalstresses.

10. VI.
HOMEOSTASIS
-Organismscanmaintain
internalconditionswithina
narrow range almost
constantly, despite
environmental changes,
throughhomeostasis(literally,
“steadystate”)theabilityof
theorganismtomaintain
internalconditions.