1. Nucleic acids

2. II. Nucleic Acids
Elements: C, H, O, N, P

3. Nucleic Acids Function: Stores genetic information
genes
blueprint for building proteins
DNA  RNA  proteins
transfers information
blueprint for new cells
blueprint for next generation
DNA
proteins

4. Function: store hereditary info
II. Nucleic Acids
Function: store hereditary info
DNA
RNA
Double-stranded helix
N-bases: A, G, C, Thymine
Stores hereditary info
Longer/larger
Sugar: deoxyribose
Single-stranded
N-bases: A, G, C, Uracil
Carry info from DNA to ribosomes
tRNA, rRNA, mRNA, RNAi
Sugar: ribose

5. Nucleotides: monomer of DNA/RNA
Nucleotide = Sugar + Phosphate + Nitrogen Base

6. Nucleotide phosphate A – T Nitrogen G – C base 5-C sugar Purines
Pyrimidines
Adenine
Guanine
Cytosine
Thymine (DNA)
Uracil (RNA)
Double ring
Single ring
5-C sugar

7. “Students at AG (middle school) are still PURE.
Memory Help:
“Students at AG (middle school) are still PURE.

8. Dehydration Synthesis forms the Sugar-Phosphate Backbone

9. N-bases

10. Information flow in a cell: DNA  RNA  protein

11. Carbohydrates

12. III. Carbohydrates Ratio of 1 carbon: 2 hydrogen: 1 oxygen or CH2O
Monomers = Monosaccharides (eg. glucose, ribose)

13. III. Carbohydrates
monosaccharide  disaccharide  polysaccharide

14. Sugars 6 5 3 Most names for sugars end in -ose
Classified by number of carbons
6C = hexose (glucose)
5C = pentose (ribose)
3C = triose (glyceraldehyde)
Glyceraldehyde H OH O C OH H HO
CH2OH O
Glucose H OH HO O
Ribose
CH2OH 6 5 3

15. Functional groups determine function
carbonyl
aldehyde
carbonyl
ketone

16. The structure and classification of some monosaccharides

17. Linear and ring forms of glucose

18. III. Carbohydrates Examples/Types:
Simple sugars: Fructose, Glucose, Ribose
Complex Polysaccharides: Starch, Cellulose, Glycogen

19. Differ in position & orientation of glycosidic linkage
III. Carbohydrates
Functions:
Fuel (energy) and building material
Storage (plants-starch, animals-glycogen)
Structure (plant-cellulose, arthropod/fungi-chitin)
Differ in position & orientation of glycosidic linkage

20. Building sugars Dehydration synthesis monosaccharides disaccharide H2O
maltose |
glucose |
glucose |
maltose
glycosidic linkage

21. Building sugars Dehydration synthesis monosaccharides disaccharide H2O
sucrose = table sugar |
glucose |
fructose |
sucrose
(table sugar)

22. Carbohydrate synthesis

23. Cellulose vs. Starch
Two Forms of Glucose:  glucose &  glucose

24. Cellulose vs. Starch Starch =  glucose monomers
Cellulose =  glucose monomers

25. Storage polysaccharides of plants (starch) and animals (glycogen)

26. Linear vs. branched polysaccharides
starch
(plant)
energy storage
Can you see the difference between starch & glycogen?
Which is easier to digest?
Glycogen = many branches = many ends
Enzyme can digest at multiple ends. Animals use glycogen for energy storage == want rapid release.
Form follows function.
APBio/TOPICS/Biochemistry/MoviesAP/05_07Polysaccharides_A.swf
glycogen
(animal)

27. Polysaccharide diversity
Molecular structure determines function
in starch
in cellulose
isomers of glucose
structure determines function…

28. Structural polysaccharides: cellulose & chitin (exoskeleton)

29. Lipids: Fats & Oils

30. IV. Lipid Structure
Elements:
Monomers:
C, H, O
Fatty Acids
Glycerol*

31. IV. Lipids Fats (triglyceride): store energy
Glycerol + 3 Fatty Acids
saturated, unsaturated, polyunsaturated
Steroids: cholesterol and hormones
Phospholipids: lipid bilayer of cell membrane
hydrophilic head, hydrophobic tails
Hydrophilic head
Hydrophobic tail

32. Phospholipid

33. The structure of a phospholipid

34. Phospholipids Structure: glycerol + 2 fatty acids + PO4
PO4 = negatively charged
It’s just like a penguin…
A head at one end
& a tail at the other!

35. Phospholipids Hydrophobic or hydrophilic? fatty acid tails =
PO4 head =
split “personality”
hydrophobic
hydrophillic
“attracted to water”
Come here, No, go away!
interaction with H2O is complex & very important!
“repelled by water”

36. Phospholipids in water
Hydrophilic heads “attracted” to H2O
Hydrophobic tails “hide” from H2O
can self-assemble into “bubbles”
bubble = “micelle”
can also form a phospholipid bilayer
early evolutionary stage of cell?
water
bilayer
water

37. Why is this important? Phospholipids create a barrier in water
define outside vs. inside
they make cell membranes!
Tell them about soap!

38. Hydrophobic/hydrophilic interactions make a phospholipid bilayer

39. Building Fats Triacylglycerol 3 fatty acids linked to glycerol
ester linkage = between OH & COOH
hydroxyl
carboxyl
BIG FAT molecule!!

40. Dehydration synthesis
H2O
dehydration synthesis
enzyme
H2O
Pulling the water out to free up the bond
enzyme
H2O
enzyme
H2O

42. Saturated Unsaturated Polyunsaturated
“saturated” with H, so NO double bonds
Have some C=C (double bonds), result in kinks
In animals
In plants
Solid at room temp.
Liquid at room temp.
Eg. butter, lard
Eg. corn oil, olive oil

43. Cholesterol, a steroid

44. Cholesterol Important cell component animal cell membranes
precursor of all other steroids
including vertebrate sex hormones
high levels in blood may contribute to cardiovascular disease

45. Cholesterol Important component of cell membrane
helps keep cell membranes fluid & flexible

46. From Cholesterol  Sex Hormones
What a big difference a few atoms can make!
Same C skeleton, different functional groups