Amino Acids - w1

Question 1

What are the two main molecular groups in an amino acid?

Answer 1

carboxyl group (COO-) and amino group (H3N+)

Question 2

What type of peptide chains are short (<20 AAs)

Answer 2

oligopeptide

Question 3

What is the bond between amino acids?

Answer 3

peptide bond

Question 4

What are zwitterions?

Answer 4

ions that have a positively charged area on one end and a negatively charged area on the other end

Question 5

What initially breaks down dietary proteins in our stomach?

Answer 5

HCl and pepsin

Question 6

What breaks down denatured proteins and peptides?

Answer 6

pancreatic enzymes

Question 7

What is the acronym for essential AAs?

Answer 7

Try THis VIP MaLL

Question 8

How many AAs are essential?

Answer 8

nine

Question 9

What are the three ways the body can get nonessential amino acids?

Answer 9

tricarboxylic acid, glycolysis, from an essential SS

Question 10

If the pH of a medium is higher than the pKa of the amino acid, what happens?

Answer 10

deprotonation (loss of H+)

Question 11

What are the two main acidic AAs?

Answer 11

aspartate and glutamate

Question 12

What causes the acidity in aspartate and glutamate?

Answer 12

another carboxyl acid added

Question 13

What is the precursor AA that begins cysteine biosynthesis?

Answer 13

methionine

Question 14

What does a deficiency in cystathionase cause?

Answer 14

cystathioninuria

Question 15

What is the cause of homocysteinuria?

Answer 15

deficiency of CBS (increases homocysteine)

Question 16

Which cysteine synthesis disease can cause neurologic and cardiovascular disease’;

Answer 16

homocysteinuria

Question 17

What causes the formation of cystine?

Answer 17

oxidation of cysteine, causing disulfide bonds

Question 18

What disease causes kidney stones?

Answer 18

cystinuria

Question 19

What is the precursor essential AA that makes tyrosine?

Answer 19

phenylalanine

Question 20

What is the simplest AA?

Answer 20

glycine (non-polar)

Question 21

What are the two sulfur-containing AAs?

Answer 21

methionine and cysteine

Question 22

What type of AA is water solubles?

Answer 22

polar

Question 23

Which AAs do not have oxygen in their side chains?

Answer 23

non-polar (aliphatic)

Question 24

What molecular group in AAs can be easily protonated?

Answer 24

amino group (NH)

Question 25

What are the three aromatic AAs?

Answer 25

phenylalanine (e), tyrosine (ne), and tryptophan (e)

Question 26

What causes phenylketonuria (PKU)

Answer 26

defect of phenylalanine hydroxylase or defect of co-factor (dihydropteridine reductase)

Question 27

Which pt modification attaches a carbohydrate to an AA?

Answer 27

glycosylation

Question 28

Which pt modification adds a lipid molecule to AAs?

Answer 28

fatty acylation

Question 29

Which pt modification occurs on lysine residues of histone protein in chromatin?

Answer 29

acetylation

Question 30

Which pt modification modifies glutamate to form gamma-carboxyl, and occurs in clotting proteins?

Answer 30

carboxylation

Question 31

Which pt modification transfers a phosphate group on the hydroxyl group of kinases?

Answer 31

phosphorylation

Question 32

What are the three main protein kinase key in phosphorylation?

Answer 32

serine, threonine, tyrosine

Question 33

Which pt modification adds a hydroxyl group to proline and is key in stabilizing collagen?

Answer 33

hydroxylation or oxidation