Nitrogen 1

Question 1

What percentage of air is nitrogen?

Answer 1

Approx. 80%

Question 2

Define diazotrophs.

Answer 2

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

Question 3

What is the fixation step of the nitrogen cycle?

Answer 3

Nitrogen -> Ammonium

Question 4

What are the assimilation steps of the nitrogen cycle?

Answer 4

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

Question 5

What are the degradation steps of the nitrogen cycle?

Answer 5

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

Question 6

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

Answer 6

Lightening

Question 7

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

Answer 7

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

Question 8

Define cyanobacteria.

Answer 8

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

Question 9

What enzyme is deactivated by oxygen in the nitrogen cycle?

Answer 9

Nitrogenase

Question 10

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

Answer 10

Anaerobically, uncoupled, increase.

Question 11

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

Answer 11

Leghaemoglobin

Question 12

What is the nitrification process?

Answer 12

Nitrite -> Nitrate

Question 13

What binds with ammonium to form glutamate?

Answer 13

Alpha-ketoglutarate

Question 14

What are the 4 most common amino acids?

Answer 14

Alanine
Glutamine
Glutamate
Aspartate

Question 15

Define transanimation

Answer 15

Conserving nitrogen by transferring amino group between different molecules.

Question 16

What do all aminotransferases rely on?

Answer 16

Pyridoxal phosphate cofactor (PLP)

Question 17

What does L-glutamine act as?

Answer 17

Temporary storage for nitrogen.

Question 18

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

Answer 18

Vitamin B6

Question 19

Aminotransferases are ______ enzymes.

Answer 19

Intracellular

Question 20

What are the steps of oxidative catabolism?

Answer 20

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

Question 21

Describe amino acid digestion in the stomach.

Answer 21

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

Question 22

Describe amino acid digestion in the intestine.

Answer 22

Membrane bound proteins degrade proteins further.