Cell, amino acid, proteins, enzymes introduction.ppt

Biochemistry

1. 1
Biochemistry
The study of the chemistry of life.
Textbook Chapter 2

2. 2
Chemistry Review
•Atom – Basic unit of matter.
•Subatomic particles of atoms:
–electrons – negatively charged particle in
constant motion around the nucleus.
–protons – positively charged. (Equals atomic #)
–neutrons – No charge.
•*Protons & Neutrons
form the nucleus of
an atom.

3. 3
It’s elemental…
•Element – a pure substance that
consists entirely of ONE type of
atom and more than 100 known
elements. There are only about 2
dozen found in living organisms.
•Compound – Substance formed by
the chemical combination of 2 or
more elements.

4. 4
Bonding
•Ionic Bonds -When electrons are
transferred from one atom to
another.
–Involves a metal and a non-metal

5. 5
Bonding, cont.
•Covalent Bonding – between two or
more non-metals. Electrons are
SHARED.
–Most of your compounds in biology are
covalently bonded!

6. 6
Covalent Bonding in Water
Oxygen
shares its 6
electrons
Each hydrogen
shares 1
electron
Oxygen now has 8 electrons around it all
times!

7. 7
Properties of Water
•Water is the single most abundant
compound in living things.
• Water has an unusually high boiling point
and freezing point
•Water expands when frozen and is less
dense as a solid
•Polarity – molecules in which the
charges are unevenly distributed that
attract like a magnet. This allows water
molecules to easily attract other water
molecules.

8. 8
States of water

9. 9
Adhesion and
Cohesion
•Water is attracted to other water. This is
called cohesion. Water can also be
attracted to other materials. This is called
adhesion.
•The oxygen end of water has a negative
charge and the hydrogen end has a
positive charge.
–The hydrogens of one water molecule are
attracted to the oxygen from other water
molecules. This attractive force is what gives
water its cohesive and adhesive properties.

10. 10
Surface Tension
•Surface tension is the name we give
to the cohesion of water molecules
at the surface of a body of water.
–All the water molecules on the surface
of the bead are 'holding' each other
together or creating surface tension.

11. 11
Capillary Action
•Capillary action is
related to the adhesive
properties of water.
•You can see capillary
action 'in action' by
placing a straw into a
glass of water. The
water 'climbs' up the
straw.
•Plants use capillary
action to pull water
into themselves

12. 12
Solutions and Suspensions
•Mixture – Materials composed of 2
or more elements or compounds
physically mixed together but not
chemically.
–Ex: salt and pepper: New substance
NOT formed.

13. 13
Solutions
•Types of mixtures made with water:
1. Solutions – components are evenly
distributed.
a. Solute – substance that is dissolved.
b. Solvent – substance which does the
dissolving.
Watch this flash movie!
*Water is the universal solvent.

14. 14
Acids and Bases
•pH Scale – scale used to determine the
concentration of Hydrogen+ ions in a
solutions. Scale ranges from 0 – 14. 7 is
an equal # of H ions (balance). Below 7=
acidic/ Above 7= basic.
•Acid – high concentrations of H ions.
•Base – low concentrations of H ions.

15. 15

16. 16
More about pH
•Buffer – weak acid or base that can
react with strong acids or bases to
prevent sharp, sudden changes in
the pH level.
*Maintaining pH is essential to
maintaining homeostasis in living
things.

17. 17
Suspensions
•Suspension – Mixtures of water
and no dissolved materials.
–Blood is an example of a
suspension. Can you name these
other examples?

18. 18
Carbon Compounds
The basis of biochemistry

19. 19
Organic Chemistry
– Is the study of compounds that contain
carbon atoms.
Carbon can:
1.Bond with many different elements.
2.Forms millions of different, large
complex structures.
*No other element comes close to the
versatility of carbon which is why it is
found in living things.

20. 20
Molecule size
•Macromolecule – Giant molecules.
•Monomer – smaller molecules
•Polymer – many joined monomers.

21. 21
Saturated vs. Unsaturated
•Saturated Fats – solid form of fats.
These fats do not break down easily.
They can cause hardening of the
arteries. Only found in animal
products.
•Polyunsaturated Fats – liquid at
room temperature. Ex: cooking oils,
such as corn, sesame, olive oil.
Found in plant products.

22. 22
Nucleic Acids
•Nucleic Acids – macromolecule -
largest in the body. Forms and
transmits the genetic code.
•Nucleotides – polymers assembled
from individual monomers.
–3 parts:
•Sugars/ Phosphates/ Nitrogen Bases.

23. 23
Nucleotides
•2 types of Nucleotides:
–a. DNA – deoxyribonucleic acid. The
master copy of the information code.
–b. RNA – ribonucleic acid. Makes
protein molecules.

24. 24
4 Groups of Organic
Compounds
of Living Things

25. 25
Carbohydrates
Carbohydrates – main source of energy in living
things. (starches/sugars)
–a. monosaccharides – single sugar
molecules. Glucose, galactose (milk), fructose
(fruits)
–b. polysaccharides – excess sugar stored in
animals & plants.
•1. glycogen – sugar stored as in animal
tissues.
•2. Cellulose – sugar stored in plant tissues.
The tough, flexible fibers found in plants.

26. 26
Lipids
•Lipids – not soluble in water. Fats,
oils, waxes.
–Store energy,
–make up membranes
–coverings in living things
–Steroids are lipids too.

27. 27
Proteins
•Proteins – polymer of molecules
called amino acids.
–Each protein has a specific job such as
cellular components and muscles and
bones.

28. 28
Amino Acids
•Amino Acids – building blocks of
proteins. More than 20 types found
in nature.

29. 29
Chemical Reactions &
Enzymes
*Everything that happens in an
organism. Growth, interactions with
the environment, movement, etc. are
based on chemical reactions.
•Chemical Reaction – process that
changes 1 set of chemicals into
another. Always involves change
and cannont be undone.

30. 30
Chemical Reactions
•Energy exchanges – energy is
released anytime chemical bonds
form or break.
•Activation energy – energy needed
to get a reaction started.
•Enzymes – proteins that speed up
chemical reactions.
•Catalyst – substance that speeds
up the rate of chemical reactions

31. 31
How do Enzymes Work?
1. Substrates – sites where reactions
can be brought together. Bonds to
the site on the enzyme which fits just
right like a lock and key.
2. Regulation – cells that contain
proteins that can turn “on” or “off”
enzymes when needed.