Respiration

Question 1

In order for energy from carbohydrates to be utilised, all di and polysaccharides must be ……. To form a monosaccharide (glucose = 80%, fructose and galactose = 20%)

Answer 1

Hydrolysed

Question 2

Fructose and galactose are converted by the …… into glucose

Answer 2

Liver

Question 3

homeostatic mechanisms maintain blood glucose at approximately ……mmol/L (100mg/ dL)

Answer 3

5.6

Question 4

Glucose is the body’s preferred energy source for the production of ATP, but it is also used for:

Answer 4

-amino acid synthesis
-glycogen synthesis
-triglyceride synthesis

Question 5

Glucose movement into a cell

Answer 5

-before glucose can be used it use enter a cell
-it passes through the plasma membrane and enters the cytosol
-cell markers allow glucose to enter the cell, the glucose is then altered so the marker wont let it out again

Question 6

What are the steps of aerobic respiration and anaerobic respiration and where do they occur?

Answer 6

Question 7

What are the two other names for the krebs cycle

Answer 7

-citric acid cycle
- tricarboxylic acid (TCA) cycle

Question 8

Describe glycolysis

Answer 8

1. Glucose phosphorylated to glucose phosphate
   -Using inorganic phosphates from 2 ATP
2. Hydrolysed to 2 x triose phosphate
3. Oxidised to 2 pyruvate
   -2 NAD reduced
   -4 ATP regenerated (net gain of 2)

Question 9

Describe the NAD regeneration

Answer 9

1. Pyruvate converted to lactate (animals & some bacteria) or ethanol (plants & yeast)
2. Oxidising reduced NAD → NAD regenerated
3. So glycolysis can continue (which needs NAD) allowing continued production of ATP

Question 10

Lactate is produced in …….. when the conc of…….is low to regenerate NAD+ and allow anaerobic energy production

Answer 10

-muscle
-02

Question 11

Describe the link reaction and kreb cycle

Answer 11

LINK REACTION

1. Pyruvate oxidised (and decarboxylated) to acetate
   -CO2 produced
   -Reduced NAD produced (picks up H)
2. Acetate combines with coenzyme A, forming Acetyl Coenzyme A

(Products per glucose molecule: 2 x Acetyl Coenzyme A, 2 X CO2 and 2 X reduced NAD)

KREBS CYCLE

1. Acetyl coenzyme A (2C) reacts with a 4C molecule
   - Releasing coenzyme A
   -Producing a 6C molecule that enters the Krebs cycle
2. In a series of oxidation-reduction reactions, the 4C molecule is regenerated and:
   -2xCO2lost
   - Coenzymes NAD & FAD reduced
   -ATP produced

Question 12

Describe oxidative phosphorylation

Answer 12

1. Reduced NAD/FAD oxidised to release H atoms → split into protons (H+) and electrons (e-)
2. Electrons transferred down electron transfer chain (chain of carriers at decreasing energy levels)
   -By redox reactions
3. Energy released by electrons used in the production of ATP from ADP + Pi (chemiosmotic theory):
   -Energy used by electron carriers to actively pump protons from matrix → intermembrane space
   -Protons diffuse into matrix down an electrochemical gradient, via ATP synthase (embedded)
   -Releasing energy to synthesise ATP from ADP + Pi
4. In matrix at end of ETC, oxygen is final electron acceptor (electrons can’t pass along otherwise)
   -So protons, electrons and oxygen combine to form water

Question 13

Answer 13

Question 14

Answer 14

Question 15

Which cycle is this ?

Answer 15

Cori cycle