Biological Molecules and Enzymes

Question 1

Roles of Lipids

Answer 1

energy storage, cellular organization/structure, precursor molecules for vitamins and hormones

Question 2

Adipocytes

Answer 2

Fat cells mainly containing triglycerides

Question 3

Phospholipids

Answer 3

Lipids with phosphate attached; imp in membrane formation with phosphoglycerides

Question 4

Glycolipids

Answer 4

Lipids with carbohydrate attached; imp in membranes of myelinated cells of nervous system

Question 5

Steroid

Answer 5

Four ringed structure (some hormones, vit D, cholesterol

Question 6

Waxes

Answer 6

Ester linkage between long-chain alcohol and long chain FA

Question 7

Lipoproteins

Answer 7

Carry lipids through blood

VLDL, LDL, HDL

Question 8

Roles of Carbohydrates

Answer 8

Energy storage, structure

Question 9

Glucose

Answer 9

6C hexose
              H
               |
         O=C
               |
          H-C-OH
               |
        HO-C-H
               |
          H-C-OH
               |
          H-C-OH
               |
              CH2OH

Question 10

Roles of Nucleotides

Answer 10

Used in energy use (ATP) and building genetic material

Question 11

Nucleoside

Answer 11

Pentose Sugar + Nitrogenous base

Question 12

Nucleotide

Answer 12

Nucleoside + phosphate group

Question 13

Purines

Answer 13

Two ringed, A and G

Question 14

Pyrimidines

Answer 14

Three ringed, C and T (U in RNA)

Question 15

Roles of Amino Acids

Answer 15

Building blocks of proteins

Question 16

Peptide bond

Answer 16

O
||
-HN-C-CHR-

Question 17

Polar Amino Acids (6)

Answer 17

Serine, Thronine, Cysteine, Asparagine, Tyrosine, Glutamine

Question 18

Acidic Amino Acids (2)

Answer 18

R group has -COOH

Aspartic Acid, Glutamic Acid

Question 19

Basic Amino Acids (3)

Answer 19

R group has -NH2

Histidine, Lysine, Arginine

Question 20

Non-Polar Amino Acids (9)

Answer 20

Glycine, Alanine, Valine, Leucine, Isoleucine, Phenylalanine, Tryptophan, Methionine, Proline

Question 21

Primary Protein Structure

Answer 21

AA in polypeptide

Question 22

Secondary protein structure

Answer 22

Alpha helix or Beta pleated sheet

H bonds reinforce

Question 23

Tertiary protein structure

Answer 23

3D shape due to disulfide bonds (btw cysteine), electrostatic forces, H bonds, vand der Waals forces, hydrophobic bonding, proline kinks

Question 24

Quaternary protein structure

Answer 24

2+ polypeptide chains bind together

Question 25

Globular proteins

Answer 25

Function as enzymes (pepsin), hormones (insulin), membrane pumps (Na/K), channels, memb receptor, transport/storage, osmotic regulation (albumin), immune response (antibodies)

Question 26

Proteoglycans

Answer 26

Proteins + carbs (50%+)

Question 27

Role of Minerals

Answer 27

Transport, strength to matrix, cofactors in enzyme function

Question 28

Enzyme lock and key model vs induced fit

Answer 28

Lock key: specific shape substrate fits | Induced fit: shapes alter upon binding

Question 29

Vmax

Answer 29

Max reaction rate | Proportional to [enzyme]

Question 30

Michaelis constant Km

Answer 30

V(o)=(Vmax[S])/(Km + [S]) The [substrate] where the reaction rate is 1/2 Vmax Km inversely proportional to enzyme substrate affinity Km doesn't vary when [enzyme] is changed

Question 31

Coenzymes

Answer 31

Cosubstrates: reversibly bind to spec enzyme (ATP) | Prosthetic grps: remain covalently bound throughout rxn (heme)

Question 32

Proteolytic cleavage

Answer 32

Irreversible covalent modification as with zymogens

Question 33

Reversible covalent modification

Answer 33

Activated/deactivated by phosphorylation

Question 34

Allosteric interactions

Answer 34

Modification of enzyme's configuration through binding of activator/inhibitor to specific binding spot

Question 35

+ Cooperativity

Answer 35

Binding of one substrate facilitates increased binding

Question 36

Competitive inhibitor

Answer 36

``` Binds on enzyme active site Inhibits binding of substrate Increases Km Doesn't change Vmax Rate of rxn compensated for by increase [substrate] ```

Question 37

Uncompetitive inhibitor

Answer 37

``` Binds on E-S complex Doesn't inhibit binding of substrate Decreases Km Decreases Vmax Rate of rxn can't be compensated for by inc substrate ```

Question 38

Mixed inhibitor

Answer 38

Binds to 1. active site or 2. E-S complex Doesn't inhibit binding of substrate 1. Increases or 2. decreases Km Decreases Vmax

Question 39

Non-competitive inhibitor

Answer 39

Binds to E-S complex or active site Doesn't inhibit substrate binding Doesn't change Km Decreases Vmax

Question 40

Kinase

Answer 40

Phosphorylates a molecue

Question 41

Phosphatase

Answer 41

Dephosphorylates a molecule