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Flashcards in Nitrogen 1 Deck (22)
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1
Q

What percentage of air is nitrogen?

A

Approx. 80%

2
Q

Define diazotrophs.

A

Take gaseous nitrogen and turn it into molecules containing nitrogen for plants/animals.

3
Q

What is the fixation step of the nitrogen cycle?

A

Nitrogen -> Ammonium

4
Q

What are the assimilation steps of the nitrogen cycle?

A

Ammonium -> Glutamate -> Other amino acids -> proteins

5
Q

What are the degradation steps of the nitrogen cycle?

A

Proteins -> Other amino acids -> Glutamate -> Ammonium -> Nitrogen

6
Q

What is the only natural thing with enough energy to break a N2 bond?

A

Lightening

7
Q

What man made process can be used to break the N2 bond? What are the necessities for the process to work?

A

Haber process (400 degrees celsius, 200 atm with iron catalyst).

8
Q

Define cyanobacteria.

A

Nitrogen fixing bacteria found in lakes and root nodules of legume.

9
Q

What enzyme is deactivated by oxygen in the nitrogen cycle?

A

Nitrogenase

10
Q

Nitrogen fixing bacteria live ______ with ______ mitochondria to ______ electron flow and burn off oxygen.

A

Anaerobically, uncoupled, increase.

11
Q

What do leguminous plants produce to bind to oxygen and keep concentration low enough to not inhibit nitrogenase?

A

Leghaemoglobin

12
Q

What is the nitrification process?

A

Nitrite -> Nitrate

13
Q

What binds with ammonium to form glutamate?

A

Alpha-ketoglutarate

14
Q

What are the 4 most common amino acids?

A

Alanine
Glutamine
Glutamate
Aspartate

15
Q

Define transanimation

A

Conserving nitrogen by transferring amino group between different molecules.

16
Q

What do all aminotransferases rely on?

A

Pyridoxal phosphate cofactor (PLP)

17
Q

What does L-glutamine act as?

A

Temporary storage for nitrogen.

18
Q

What is the cofactor involved in the nitrogen cycle derived from?

A

Vitamin B6

19
Q

Aminotransferases are ______ enzymes.

A

Intracellular

20
Q

What are the steps of oxidative catabolism?

A

Leftover amino acids degraded
Dietary a/a exceed protein synthesis needs degraded
Proteins broken down when carbs in short supply

21
Q

Describe amino acid digestion in the stomach.

A

Acidic environment + enzymes -> free a/a + di/tri peptides

22
Q

Describe amino acid digestion in the intestine.

A

Membrane bound proteins degrade proteins further.