Biochemistry

Question 1

4 elements of protein structure

Answer 1

Primary- linear amino acid sequence
Secondary- alpha helices and beta-pleated sheets
Tertiary- Folding protein into 3 dimensional shape
Quaternary- multisubunit protein complex

Question 2

Enzymes are characterized by

Answer 2

Specificity, high rate of activity, affinity for their specific substrate (Km), and the maximal rate of reaction when substrate is present in excess concentration (Vmax)

Question 3

Coenzymes

Answer 3

Most vitamins and certain metals act as coenzymes that facilitate enzyme catalytic activity

Question 4

Carbohydrates are stored as

Answer 4

glycogen in the liver and muscle

Question 5

DNA and RNA 3 main components

Answer 5

Purine or pyrimidine base molecule, sugar, phosphoric acid molecule

Question 6

Protein synthesis occurs

Answer 6

on the ribosome where mRNA carries the message and directs the order of AA in the protein, tRNA delivers each amino acid per code, and rRNA catalyzes the assembly of amino acids into protein

Question 7

4 major biomolecules

Answer 7

carbohydrates, amino acids, fatty acids, nucleotides

Question 8

Biomolecules are building blocks for

Answer 8

polysaccharides, lipids, proteins, and polynucleotides

Question 9

Proteins

Answer 9

Form the structural backbone of cells and tissues and are responsible for enzymatic reactions, membrane transport, hormonal regulation, immune system, and transmission of cell to cell messages

Question 10

All amino acids contain

Answer 10

An amino group and a carboxylic acid group and fall into 2 large groupings (primary and secondary amines)

Question 11

Primary amine

Answer 11

nitrogen atom has only one bond to the carbon

Question 12

Secondary amine

Answer 12

Nitrogen atom is bonded to two carbon atoms

Question 13

Basic amino acids

Answer 13

Lysine, arginine, and histidine

Question 14

Acidic amino acids

Answer 14

Glutamate and aspartate

Question 15

9 essential amino acids

Answer 15

histine, leucine, isoleucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine

Question 16

AA of the urea cycle

Answer 16

Urea cycle- conversion of ammonia to urea

arginine, ornithine, and citrulline

Question 17

Urea cycle

Answer 17

Conversion of ammonia to urea
Main pathway for excretion of nitrogen waste product from protein metabolism. Coordinated in the cytoplasm and mitochondria of the cell.

Question 18

Peptide bond

Answer 18

formed between two AA and is the primary element of peptide and protein structure.
Formed in the ribosome
In bond formation direction, loses water, in bond hydrolysis direction gains water

Question 19

Sickle cell anemia

Answer 19

SNP replacing glutamic acid with valine

Question 20

No post-translational modification of which AA have been identified?

Answer 20

Ala, Gly, Ile, or Val

Question 21

Composition of carbohydrates

Answer 21

Carbon, hydrogen, and oxygen

Question 22

During fasting, glycogen can be

Answer 22

hydrolyzed to release glucose and maintain blood sugar levels

Question 23

ABO human blood types

Answer 23

Specific glycosylation of cell surface proteins (glycoproteins) as well as the same specific glycosylation of membrane lipids is the base of human blood groups.

Question 24

Lipids include

Answer 24

fatty acids, cholesterol, essential vitamins, and glycerides

Question 25

Long chain fatty acids/ phospholipids are precursors for

Answer 25

prostaglandins and leukotrienes

Question 26

Difference between a nucleoside and a nucleotide

Answer 26

Nucleoside- deoxyribose and nitrogenous base pair (AT or CG) | Nucleotide- one to three phosphate groups are added

Question 27

Exons

Answer 27

Sections of DNA that carry specific genes

Question 28

Introns

Answer 28

Sections of DNA that carry no genetic information

Question 29

Enzymes

Answer 29

Basically catalysts, assist in chemical reactions but are not consumed in the reaction. Accelerate the chemistry of getting from a substrate to a product. Accomplish this by lowering the activation energy.

Question 30

Key elements of enzyme-assisted reactions

Answer 30

Specificity- only one or a limited number of closely related substrates Acceleration- Reaction occurs manifold over what would normally occur

Question 31

Stearic or induced fit

Answer 31

The active site of an enzyme is spatially configured to accept only one substrate configuration or a very limited number. This model involves molecular size, orientation or reactive groups, ionic and hydrogen bonding, and possibly movement of the enzyme protein backbone. This model has replaced the original lock and key model of enzyme activity.

Question 32

How do enzymes accomplish their goals? Many explanations exist, but they fall into the following basic categories:

Answer 32

Stearic or induced fit Localized chemistry Transition state

Question 33

An enzyme without its cofactor is an

Answer 33

Apoenzyme or apoprotein

Question 34

Niacin

Answer 34

Can be converted into 2 coenzymes- NAD and NADP

Question 35

Cofactors

Answer 35

Coenzymes that are metals

Question 36

Fat soluble vitamins

Answer 36

A, D, E, K

Question 37

Deficiency associated with Vitamin A

Answer 37

Night blindness

Question 38

Deficiency associated with vitamin D

Answer 38

Rickets

Question 39

Deficiency associated with B2 or B3

Answer 39

Pellagra

Question 40

Deficiency associated with B1/thiamine

Answer 40

Beriberi

Question 41

First order reaction

Answer 41

Substrate goes to product without interaction of another molecule, except the enzyme V=ds/dt=ks

Question 42

Glycolysis

Answer 42

Carbohydrate metabolism | 30-32 moles ATP per mole of glucose

Question 43

Gluconeogenesis

Answer 43

Glucose can be synthesized from noncarbohydrate precursors predominantly in the liver

Question 44

Precursor molecules to glucose

Answer 44

Lactate, pyruvate, glycerol, and keto-acids

Question 45

Ketone bodies

Answer 45

Acetoacetate, beta-hydroxybutyrate, and acetone Concentrations can rise in ketosis or ketoacidosis Brain and heart use ketone bodies as a direct energy source through reconversion to acetyl-coa

Question 46

Propionyl vs acetyl-CoA

Answer 46

If the original fatty acid molecule contains an even number of carbons, then acetyl-CoA is the only product. If the fatty acid chain contains an odd number of carbons, then the terminal product is propionyl-CoA.

Question 47

Cause of DNA damage, missing base

Answer 47

Removal or purine nucleotides by heat or acid

Question 48

Cause of DNA damage, altered base

Answer 48

Alkylating agents, ionizing radiation

Question 49

Cause of DNA damage, wrong base

Answer 49

Deamination

Question 50

Cause of DNA damage, deletion or insertion

Answer 50

Intercalating chemicals

Question 51

Cause of DNA damage, cyclobutyl dimer

Answer 51

UV irradiation

Question 52

Cause of DNA damage, strand breaks

Answer 52

Ionizing radiation, chemicals

Question 53

Cause of DNA damage, strand-cross linking

Answer 53

Chemicals