Cell metabolism

Question 1

What are the three main nutrient types?

Answer 1

Growth, maintenance, repair

Question 2

What do carbs provide?

Answer 2

Glucose

Question 3

What do proteins provide?

Answer 3

Amino acids

Question 4

What do fats/oils provide?

Answer 4

Fatty acids

Question 5

What is the role of liver cells?

Answer 5

Convert one type of food molecule to another

Question 6

What is the major fuel of the cell?

Answer 6

Glucose

Question 7

Respiration equation

Answer 7

C6H12O6 + 6O2 ->6CO2 + 6H2O
ADP+Pi ->ATP

Question 8

How is excess glucose stored?

Answer 8

• 99% stored as adipose tissue (fat)
• 1% stored in liver and skeletal muscle (glycogen)

Question 9

Chemical reactions

Answer 9

Provide energy needed to maintain homeostasis
Perform essential functions

Question 10

What is catabolism?

Answer 10

Large to small
Energy released

Question 11

What is anabolism?

Answer 11

Small to large
Energy used

Question 12

The molecules formed by anabolism:

Answer 12

• Perform structural maintenance/repair
• Support growth
• Produce secretions
• Build nutrient reserves

Question 13

What are the three stages of oxidation of glucose to produce ATP?

Answer 13

1) Glycolysis - in the cytoplasm - with or without oxygen = anaerobic

2) Krebs cycle aka citric acid cycle
3) ETC - both in the mitochondria - require oxygen = aerobic

Question 14

Carbs are catabolised into

Answer 14

Glucose

Question 15

Fats are catabolised into

Answer 15

Fatty acids and glycerol

Question 16

Proteins are catabolised into

Answer 16

Amino acids

Question 17

Glucose, fatty acids and glycerol and amino acids can enter the krebs cycle…

Answer 17

Releasing energy and Co2

Question 18

Gluconeogenesis:

Answer 18

Glucose created from non-carb carbon sources, to maintain blood glucose levels during fasting or other periods of low carb availability
krebs cycle -> Pyruvate + glycerol + lactic acids + fatty acids + amino acids (60%) -> Glucose

Question 19

Carbohydrate (glucose) catabolism equation

Answer 19

Amino acids from protein breakdown
+
fatty acids liberated from adipose tissue
+
pyruvate from glycolysis
+
oxygen from haemoglobin in blood or from muscle cells
=
34/36 ATP
3436 ATP + H2O + CO2 + Heat

Question 20

Glycolysis

Answer 20

Breaking glucose
Occurs in cytosol
Anaerobic
Pyruvate can enter 2 pathways
2 minutes of energy
(2ATP released)

Question 21

Krebs cycle

Answer 21

Repeating sequence of reactions
Occurs in mitochondria
Anaerobic
One CO2 removed from pyruvate
leaving acetyl group to be picked to -> acetyl CoA

Question 22

ETC

Answer 22

Series of electron transporters embedded in the inner mitochondrial membrane that shuttles electrons from NADH and DADH2 to molecular oxygen

Question 23

Increased loss of nutrients caused by

Answer 23

Malabsorptions
Diarrhoea
Glycosuria
Haemorrhage

Question 24

Reduced nutrient intake caused by

Answer 24

Nausea
Anorexia
Poverty
Pain
Dysphagia

Question 25

Increased use of nutrients in the body

Answer 25

Fever Infection Burns Trauma and surgery