Chapter 18

Question 1

Most amino acids are metabolize in the __________

Answer 1

Liver

Question 2

_____________ participates in the transfer of alpha-amino groups to alpha-ketoglutarate

Answer 2

Pyridoxal phosphate

Question 3

In the first step of catabolism of an L amino acids is the removal of the amino group which is catalyzed by enzyme called ______________

Answer 3

Aminotransferase

Question 4

In the ______________ reaction of the removal of the amino acid, the alpha amino group is transferred to the alpha carbon atom of alpha-ketoglutarate, which formed an alpha alpha keto acid in the process

Answer 4

Transamination

Question 5

The purpose of the transamination reactioon is to collect the amino group from many different amino acid in the form of ______________ which then acts as an amino group donor for other pathways or exertion pathways that eliminate amine (NH3+)

Answer 5

Glutamate

Question 6

When an amino acid & ketoglutarate react they exchange the amino group & the_____________ (so the amino acid becomes the keto acid & ketoglutarate turns into glutamate (transamination reaction)

Answer 6

keto group

Question 7

In many aminotransferase reactions, alpha ketoglutarate is the amino group __________ (all aminotransferase pyridoxal phosphate (PLP) as a cofactor) (or prosthetic group)

Answer 7

Pyridoxal phosphate

Question 8

The enzyme are named for the aminotransferase based on the ____________ amino acid being used

Answer 8

Specific (alanine aminotransferase)

Question 9

____________ releases its amino group ammonia in the liver

Answer 9

Glutamate

Question 10

In an a transamination reaction the amino group & keto group ___________

Answer 10

Switches

Question 11

Glutamate is transported from the cytosol into mitochondria where it undergoes oxidative deamination which is catalyzed by__________________

Answer 11

L-glutamate dehydrogenase (Glu-dHase) (uses NAD+ or NADP+ as a cofactor)

Question 12

The combined action of an aminotransferase & glutamate dehydrogenase is referred to as __________________

Answer 12

Transdeamination

Question 13

Glutamine transport _______________ in the bloodstream

Answer 13

ammonia

Question 14

___________ is critical to intracellular amino group metabolism because its converted to glutamine

Answer 14

Glutamate

Question 15

The free amino produced with glutamate to yield glutamine is catalyzed by ___________________

Answer 15

Glutamine synthase

Question 16

Excess ammonia in tissues is added to glutamate to form glutamine a process catalyzed by________________ & after transport in the bloodstream enters the liver & NH4+ is released in mitochondria by the enzyme ____________

Answer 16

glutamine synthase, glutaminase

Question 17

The NH4+ is released in the mitochondria where the enzyme glutamine synthase converts glutamine to glutamate & NH4+ is transported in the blood to the liver where it’ll be disposed of by ____________

Answer 17

Urea synthesis

Question 18

______________ transports am onia from skeletal muscles to the liver

Answer 18

Alanine

Question 19

Alanine transports amino group to the liver via the ________________

Answer 19

glucose alanine cycle

Question 20

The glucose alanine cycle allows the energetic burden of _________________ to be imposed on the liver rather than the muscle & all available ATP in the muscle is devoted to muscle contraction

Answer 20

gluconeogenesis

Question 21

All the __________ in our body gets trapped by ketoglutarate & ketoglutarate is converted to glutamate with the amine

Answer 21

amine (NH3)

Question 22

The cycle between ketoglutarate turning into _________________ & glutamate going through its reaction to release the amine & convert back to ketoglutarate is constant

Answer 22

glutamate

Question 23

Asperate will react to form ______________ as its keto acid

Answer 23

Oxalacetate

Question 24

Glu, Gln will react to form _________________ as its keto acid

Answer 24

alpha-ketoglutarate

Question 25

Alanine will react to form _______________ as its keto acid

Answer 25

Pyruvate

Question 26

The enzyme responsible for removing the amino off the glutamate to form ketoglutarate is _________________

Answer 26

Glu-dHase (glutamate dehydrogenase)

Question 27

In the cycle reaction between _______ _________& glutamate the glutamate turns back into ketoglutarate by reacting with NADP+ to make NAPH which then make an intermediate & that intermediate reacts with water to release the amine (NH4-) to form ketoglutarate (This reaction is catalyzed by the Glu-dHase enzyme)

Answer 27

ketoglutarate