Proteins

Question 1

Which amino acids are precursors for catecholamine?

Answer 1

Phe and Tyr

Question 2

What is marasmus?

Answer 2

severe malnutrition caused by nutrient deficiencies, especially proteins and carbohydrates

Question 3

Which amino acid does melatonin come from?

Answer 3

tryptophan

Question 4

Which amino acid does nitric oxide come from?

Answer 4

arginine

Question 5

Which amino acid is an important methyl donor?

Answer 5

Met

Question 6

Which amino acid does niacin come from?

Answer 6

tryptophan

Question 7

Which amino acids are purely ketogenic?

Answer 7

Leu and Lys

Question 8

What is the chemical difference between pyruvate and alanine?

Answer 8

NH3 group

Question 9

Name the positively and negatively charged amino acids.

Answer 9

positive: Lys, Arg, His
negative: Asp, Glu

Question 10

Name the six polar uncharged amino acids.

Answer 10

Ser, Thr, Cys, Met, Asp, Gln

Question 11

Which amino acids can disrupt normal secondary protein structure?

Answer 11

Pro, Gly

Question 12

Which amino acid does dopamine come from?

Answer 12

tyrosine, which comes from phenylalanine

Question 13

Which amino acids are both ketogenic and glucogenic?

Answer 13

Tyr, Ile, Phe, Trp

Question 14

What are the ten essential amino acids?

Answer 14

Phe, Val, Thr, Trp, Ile, Met, His, Arg, Lys, Leu

Question 15

Where in the cell does protein synthesis occur?

Answer 15

cytoplasm

Question 16

Is the urea cycle reversible?

Answer 16

no

Question 17

What two amino acids are acidic and negatively charged at body pH?

Answer 17

Asp, Glu

Question 18

Which group of amino acids is associated with maple syrup disease?

Answer 18

branched chain amino acids (Val, Leu, Ile)

Question 19

Which two amino acids are essential during growth, but not the rest of the time?

Answer 19

Arg, His (conditionally essential)

Question 20

Which amino acids does heme come from?

Answer 20

porphyrin comes from glycine

Question 21

NH4 + CO2, leads to ___, which enters the urea cycle where?

Answer 21

carbamoyl phosphate

enters at the conversion of ornithine to citrulline

Question 22

Which reactions of the urea cycle happen in the mitochondria?

Answer 22

carbamoyl phosphate is formed and is added to ornithine to make citrulline

Question 23

What amino acid is a precursor of GABA?

Answer 23

Glu

Question 24

Disulfide bonds are created between adjacent molecules of which amino acid?

Answer 24

Cysteine

Question 25

Which amino acid does norepinephrine and epinephrine come from?

Answer 25

tyrosine, via dopamine

Question 26

What is an enzyme that hydrolyzes a peptide bond called?

Answer 26

proteolytic enzyme

Question 27

List six nonpolar, aliphatic amino acids.

Answer 27

Gly, Ala, Val, Leu, Ile, Pro

Question 28

Name the five steps of the urea cycle, starting with aspartate.

Answer 28

aspartate to arginosuccinate to arginine to ornithine to citrulline to arginosuccinate

Question 29

What organs does the urea cycle occur in?

Answer 29

primarily in the liver, also kidney

Question 30

Which amino acids can be glycosylated? What is the clinical significance?

Answer 30

Ser, Thr, and Lys The lysine moiety of heme gets glycosylated in hyperglycemia (HbA1c)

Question 31

What is the function of the urea cycle?

Answer 31

dispose of excess nitrogen

Question 32

What are the three secondary structural conformations for proteins?

Answer 32

alpha helix, beta sheet, random coil

Question 33

Which amino acid does thyroxine come from?

Answer 33

tyrosine, which comes from phenylalanine

Question 34

Which amino acid can form serotonin and niacin?

Answer 34

Trp

Question 35

What part of the cell does the urea cycle occur in?

Answer 35

1st 2 rxns: mitochondria the rest in the cytoplasm

Question 36

What are the immediate precursors of both molecules that make up urea (ammonium and aspartate)?

Answer 36

glutamate provides free ammonium and is also converted into aspartate

Question 37

Name the three aromatic amino acids.

Answer 37

Phe, Tyr, Trp

Question 38

Name the two purely ketogenic amino acids.

Answer 38

Leu, Lys

Question 39

How many nitrogen are in urea?

Answer 39

2

Question 40

What amino acid does creatinine come from?

Answer 40

Arg

Question 41

Define negative nitrogen balance.

Answer 41

nitrogen loss exceeds incorporation

Question 42

Which amino acid does NADP come from?

Answer 42

Trp, via niacin

Question 43

What role does alanine play in nitrogen transport?

Answer 43

alanine carries nitrogen groups from muscles to liver

Question 44

What is kwashiorkor?

Answer 44

protein malnutrition resulting in skin lesion, edema, liver malfunction (fatty change)

Question 45

Which amino acid does urea come from?

Answer 45

Arg (NH3 is donated by glutamate)

Question 46

Which amino acid is involved in the detoxification of ammonia?

Answer 46

Gln

Question 47

Which amino acids are also important excitatory neurotransmitters?

Answer 47

Asp, Glu

Question 48

Name the nine hydrophobic amino acids.

Answer 48

Gly, Ala, Val, Leu, Ile, Pro, Phe, Tyr, Trp

Question 49

Which amino acid does histamine come from?

Answer 49

His

Question 50

Which amino acid does serotonin come from?

Answer 50

Trp

Question 51

Which amino acid is an important physiological (pH) buffer?

Answer 51

His