nitrogen

Question 1

State the main nitrogen containing molecules in the body.

Answer 1

Nitrogen is found mainly in amino acids, ammonia and urea within the body.

Question 2

how does the very stable N2 get into our systems

Answer 2

its ‘fixed’ to ammonium where it then goes through nitrification and gets into our system via glutamate

Question 3

how dose nitrogen get in and out the cell

Answer 3

via glutamate

it binds with alpha-ketoglutarate

Question 4

what energy is required for ammonium and alpha-ketoglutarate to form glutamate

Answer 4

ATP and NADPH

Question 5

what are glutamine and aspartate

Answer 5

amino acids

but also neurotransmitter

Question 6

what is nitrogen assimilation

Answer 6

the process of converting nitrogen into other usable substance

Question 7

what is transamination

what are the 2 molecules always involved

Answer 7

the movement of a amino acid(nitrogen) from one molecule to another

an amino acid and a keto acid

robbing peter to pay Paul

Question 8

what are the transamination enzyme crucial for

Answer 8

creation of amino acids and in turn proteins

synthesis and degradation

Question 9

is transamination reversible or not

Answer 9

its readily reversible

Question 10

what is pyruvate

what does it become during transamination

Answer 10

an alpha-keto acid

alanine

Question 11

what does L-GlutaMINE act as

Answer 11

temporary nitrogen

donates amino acid

Question 12

what dose alpha-ketoglutarate typically do

Answer 12

accepts amino groups

Question 13

what are the transamination enzymes called

what does it rely on

Answer 13

aminotransferase

pyridoxal phosphate cofactor

Question 14

what is PLP

what’s it an example of

Answer 14

made of vitamin B6
holds on to the amino acid

ping pong reaction

Question 15

when do amino acids undergo oxidative catabolism q

Answer 15

leftover amino acids
dietary amino acids

proteins in the body are broken down – CARBS IN SHORT SUPPLY – starvation

Question 16

where are dietary proteins broken down in to peptides

by what

what size do they become

Answer 16

in the stomach

PEPSIN

di- or tri- peptides

Question 17

what hydrolysis occurs in the small intestine

Answer 17

peptides - smaller peptides = trypsin and chymotrypsin

small peptides – amino acids
= amino/carboxy PEPTIDASE

Question 18

how are digested amino acids transported

Answer 18

through the blood

Question 19

wherever nitrogen is coming from it can always be…

Answer 19

brokend down to ammonia and excreted as urea

Question 20

why is nitrogen secreted as urea

Answer 20

ammonia is toxic

ureay has very high solunility

Question 21

what is uric acid made from

Answer 21

purines

Question 22

how is ammonia transported around the blood even though its toxic

Answer 22

transported as Glutamine

Question 23

where is excess glutamine processed

Answer 23

liver, kidneys

Question 24

how is alanine formed

Answer 24

pyruvate and glutamate

Question 25

what happens during strenuous exercise to the muscle

Answer 25

muscle degradation amino acid release transamination reaction to glutamate

Question 26

when dose the glucose-alanine cycle occur

Answer 26

at the same as pyruvate is turned into lactate

Question 27

why is alanine and glutamine used for amino acid transfer

Answer 27

have no charge compared to glutamate which is negative | easier transport

Question 28

where is excess glutamate metabolised

Answer 28

in the mitochondria of hepatocytes

Question 29

what is the protein turn over per day how much is eaten

Answer 29

250g 75g

Question 30

what is ornithine

Answer 30

the carbon skeleton made by the release of urea nitrogen is added to make citrulline

Question 31

where is glutamate broken down what is produced

Answer 31

mitochondria alpha ketoglutamate aspartate and citruilline

Question 32

what is special about arginosuccinate

Answer 32

it has 2 notrogens fromed by aspartates (1 nitrogen) citrulline (1 nitrogen)

Question 33

how is urea produced

Answer 33

arginosuccinate is hydrolysed to produce Urea with the two nitrogens AND a carbon skeleton called ORNITINE - back to mitochondria

Question 34

where do amino acids entere metabolism

Answer 34

citric acid cyle intermediates pyruvate alpha ketoglutamte acytly coa

Question 35

what do the ketogenic amino acids entre metabolism what do they become

Answer 35

acetoacetyl coa acetyl coa ketone bodies

Question 36

where do glucaneogenic amino acids enter metabolism what do they become

Answer 36

citric acid cycle intermediates pyruvate glucose

Question 37

what enzyme forms glutamate

Answer 37

glutamate dehydrogenase