Cell structure and function: Cellular respiration

Question 1

Fuel for ATP

Answer 1

Carbohydrates: broken down to simple sugars
Proteins
fats

Question 2

Glucose fate

Answer 2

food -> bloodstream -> into cell by insulin
1–> cellular respiration -> cell work
2–> storage for harder times (glycogen)- bloodstream via glucagon

Question 3

cell respiration steps

Answer 3

1. glycolysis - cytosol
2. pyruvate oxidation - matrix in mitochondrion
3. citric acid cycle - matrix
4. electron transfer chain - across inner membrane

Question 4

Glycolysis

Answer 4

lysis of glucose into 2 pyruvic acid
requires 2 atp (no oxygen required) and generates 4 atp and 2 NADH

Question 5

pyruvate oxidation

Answer 5

links glycolysis to krebbs.
requires oxygen.
no ATP prod.
gives 1 NADH per pyruvate plus CO2
gives acetyl CoA

Question 6

Krebbs or citric acid cycle

Answer 6

acetyl CoA requires oxygen
gives:
2 ATP
6 NADH
2 FADH2
4 CO2
per glucose molecule
multiple steps where the product of one reaction becomes the start of the next

Question 7

substrate phosphorylation

Answer 7

glycolysis and citric acid cycle:
atp generated by direct transfer (from substrate) of phosphate group to ADP

Question 8

Oxidative phosphorylation

Answer 8

atp generated from oxidation of NADH and FADH2 and the following electron transfer and proton pumping

Question 9

Electron transfer chain

Answer 9

oxidative phosphorylation with no substrate
requires oxygen
multiple proteins
4 complexes (i ii iii iv)
electron carriers oxidise (NADH i and FADH2 ii) and donate electrons to complexes facilitate hydrogen to be pumped into inner membrane space.

Question 10

chemiosmosis

Answer 10

hydrogen ions in intermembrane space rush down through ATP synthase according to concentration gradient.
turns turbine leading to phosphorylation of ADP resulting in 26 or 28 ATP per molecule

Question 11

phsphifructokinase

Answer 11

gate keeper for glycolysis
AMP stimulates it to “open gate” (continue glycolysis)
citrate and ATP inhibits it, so if their is enough ATP, glycolysis will not occur because not needed

Question 12

Blood glucose homeostasis

Answer 12

too much: beta cells trigger pancreas to release insulin
too little: alpha cells trigger secretion of glucagon to break down glycogen

Question 13

diabetes mellitus

Answer 13

inability to produce or respond to insulin. results in abnormal metabolism of carbohydrates and elevated glucose levels
-> no glucose
-> no atp
-> no glucose storage