Cell Metabolism

Question 1

Metabolic rate definition

Answer 1

The speed at which metabolic reactions take place

Question 2

Catabolic reactions

Answer 2

Breaking large molecules into smaller ones
eg. digestions
glucose } CO2 + water

Question 3

Anabolic reactions

Answer 3

Joins smaller molecules to form larger ones

eg. amino acids } proteins

Question 4

Enzymes

Answer 4

Protein biological catalysts that speed up the rate of reactions
Synthesised within the ribosomes
Active site binds with substrate

Question 5

Factors affecting enzyme activity

Answer 5

1. Temperature
2. pH
3. Enzyme concentration
4. Cofactors (vitamins)

Question 6

Optimal enzyme conditions

Answer 6

Conditions that allow the fastest substrate processing
The further from optimal conditions, the slower they react
Become denatured in extreme conditions

Question 7

Substrates - lock and key theory

Answer 7

Enzymes carry out a specific reactions because the active site is shaped for an certain substrate
Amylase - protein (substrate), polypeptides (end product)

Question 8

Activation Energy

Answer 8

A certain energy level must be reached before a reaction can take place - energy is provided by heat
Enzymes reduce the energy of reactions they catalyse

Question 9

Cellular respiration

Answer 9

Energy released from glucose breakdown is unusable

Converts ADP to ATP, when converted back to ADP, usable energy is released

Question 10

Anaerobic respiration

Answer 10

Occurs when too little oxygen is available for aerobic respiration
Pyruvate is produced in glycolysis, converted to lactic acid
Produces around 2-6 ATP
Lactic acid is broken down in the liver with oxygen

Question 11

Aerobic respiration

Answer 11

produces 38 ATP

• 2 produced in glycolysis (cytoplasm)
• 36 produced through Kreb’s cycle, electron transport chain (mitochondria)

Question 12

Cell metabolism definition

Answer 12

Chemical reactions that take place within cells