Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Science for Medicine > Nitrogen > Flashcards

Nitrogen Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What are the 3 main nitrogen containing molecules?

A

Amino acids, ammonia and urea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 3 stages of dietary protein digestion?

A

Gastric, pancreatic and intestinal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What process occurs in gastric digestion?

A

The protein is denatured by HCl which leaves it more open to the action of pepsin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What process occurs in pancreatic digestion?

A

Pancreatic enzymes create a mix of free amino acids and short peptides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What process occurs in intestinal digestion?

A

Free amino acids are absorbed into a portal system and di/tripeptides are absorbed and broken down into free amino acids in the enterocytes of the brush border membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the only enzyme that gets it’s N from ammonia?

A

Glutamate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How do most amino acids get their N?

A

From pre-existing amino acids through transaminase reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a transaminase reaction?

A

The transfer of a pair of amino acids between a pair of keto acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is each transaminase enzyme specific to?

A

Only 1 pair of amino acids and keto acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens to the remaining C skeletons of broken down proteins?

A

They can be further catabolised into intermediates for glycolysis and the CAC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are glycogenic amino acids intermediates?

A

They converted into glucose via gluconeogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are ketogenic amino acids intermediates?

A

They are catabolised for energy in the CAC or used to form ketone bodies. They provide C to acetyl CoA or actetoacetate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is needed in order for nitrogen to be transported?

A

Alanine and glutamine (both neutral)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why isn’t glutamate needed for nitrogen transport?

A

It has a -ve charge and will require a cation as it ca’t cross the membrane readily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the process by which nitrogen is transported?

A

N created by catabolised protein can be transferred back to the liver by alanine where it is built up as glucose due to transferase enzymes. This also creates urea and ammonia, which are both toxic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where does alanine transport nitrogen?

A

plasma -> liver

17
Q

Where does glutamine transport nitrogen?

A

skeletal muscle -> liver

18
Q

How is ammonia formed?

A

Through oxidative deamination

19
Q

How is urea formed?

A

Glutamate loses its N has ammonia which is fed into the Urea cycle, where it is converted into Urea

20
Q

How is urea excreted?

A

Urea must be detoxified and made water soluble by N

21
Q

What are the 3 substances that use the C of catabolised body protein are used?

A

Turned over amino acids, metabolised amino acids and alanine

22
Q

What happens when turned over amino acids take the C from catabolised body protein?

A

It forms intermediates of glycolysis, gluconeogenesis, CAC or lipid metabolism pathways

23
Q

What happens when metabolised amino acids take up the C from metabolised body protein?

A

Forms pyruvate or CAC intermediates and may become Cs of glucose

24
Q

What happens when alanine picks up the C from metabolised body protein?

A

It is simultaneously transferred from muscle to liver and allows the safe movement of C from pyruvate to glucose

25
Q

How many urea cycle metabolic disorders are there?

A

6, which include OTC, amino acid disorders and PKU

26
Q

What is OTC?

A

It is the most common urea cycle metabolic disorder. It is the only disorder that is sex-linked and causes hyperammonaemia (high blood ammonia level). It is typical in newborns

27
Q

What causes amino acid disorders?

A

A decrease in enzyme activity, so amino acids can’t be metabolised

28
Q

What are the affects of amino acid disorders?

A

Decrease product, increased precursors and alternative routes (may be toxic)

29
Q

What causes PKU?

A

An absence/deficiency of phenylalanine hydroxylase, due to increased phenylalanine levels after breast feeding

30
Q

What type of disorder is PKU?

A

Autosomal recessive

31
Q

What are the affects of PKU?

A

Increases levels of phenylalanine which is toxic, which can result in impaired brain development. Also causes a musty odour

32
Q

How is PKU treated?

A

Reducing protein in the diet using Tyrosine

33
Q

How is PKU diagnosed?

A

+ve screening test and quantitative amino acid analysis

Science for Medicine (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions