Cellular Respiration

Question 1

2 forms of energy

Answer 1

Potential energy (stored energy)
Kinetic energy(energy due to motion)

Question 2

Cellular respiration

Answer 2

Definition: A chemical process in which glucose is broken down gradually in the presence of oxygen(aerobic respiration) or in the absence of oxygen(anaerobic respiration) to release energy

Releases the energy in food, so that the organism can get the energy it requires

Question 3

2 types of cellular respiration

Answer 3

1. Aerobic: takes place in presence of oxygen (oxygen available to cell) and lots of energy is released and stored as ATP
2. Anaerobic: takes place in the absence of oxygen(oxygen is NOT available) and very little energy is released

Question 4

Where is aerobic respiration completed?

Answer 4

In the mitochondrion

Question 5

Defime Metabolism?

Answer 5

A chemical process that takes place inside our body which are controlled by enzymes

Question 6

Difference between catabolic and anabolic?

Answer 6

Catabolic: metabolic process in which complex molecules are broken down into simple ones to release energy
Anabolic: the synthesis of more complex molecules from simple molecules

Question 7

Aerobic respiration formula

Answer 7

C⁶H¹²O⁶+6O²~enzymes>6CO²+6H²O+Energy

Glucose+oxygen~enzymes>carbon dioxide+water+38ATP

Question 8

In aerobic respiration energy is released. Where is this energy stored?

Answer 8

In the mitochondria as adenosine triphosphate ATP

Question 9

ATP is a chemical containing an energy-rich bond. What happens when this bond breaks?

Answer 9

Energy is released

During aerobic respiration; 1 glucose molecule will produce a net product of 38 high energy ATP molecules

Question 10

What are the 3 stages of aerobic respiration?

Answer 10

1. Glycolysis (occurs in cytocol)
2. Krebs cycle (occurs in the mitochondria)
3. Oxidative phosphorylation (occurs in the mitochondria)

Question 11

Explain what happens during glycolysis

Answer 11

• glucose is broken down to form pyruvic acid in the cytosol
• pyruvic acid contains energy-rich hydrogen atoms
• pyruvic acid molecules move into the mitochondrion
• a net of 2ATP molecules are produced

Question 12

Explain what happens during the Krebs cycle

Answer 12

• pyruvic acid enters the mitochondrion and joins a cyclic series of reactions
• CO² and energized hydrogen atoms are released
• CO² is released from the cell, while the energized hydrogen atoms are used in the next stage

Question 13

Explain what happens during Ocidative phosphorylation

Answer 13

• the energized hydrogen atoms are used to make 36 ATP molecules
• the de-energised hydrogen atoms combine with the oxygen to for water

Question 14

What are energy carries in cells

Answer 14

ATP is a carrier of energy in cells
When energy is required, ATP breaks down to ADP+P (adenosine diphosphate and phosphate) and the energy released is available to the cell.
ATP is formed when ADP+P+energy forms ATP

Question 15

What is anaerobic respiration

Answer 15

A catabolic (breaking down) reaction that occurs in both plants and animals, when oxygen in NOT available in the cell.
Reaction occurs in the cytosol
Products are different in plants and animals

Question 16

What is the product of anaerobic respiration in plants cells

Answer 16

In plants and yeast cells, energy-rich glucose is broken down to ethanol (alcohol).
Carbon dioxide and some energy(2ATP) is released
Process is called Alcoholic fermentation (e.g beer and bread making)

Question 17

What is the product of anaerobic respiration in animal cells

Answer 17

Anaerobic respiration in animals also known as lactic acid fermentation.
Where food(glucose) is broken down to yield some energy and lactic acid
- build up of lactic acid in muscles leads to pain and muscle cramps

Question 18

What happens to lactic acid when oxygen becomes available

Answer 18

Lactic acid can be converted back into pyruvic acid when oxygen becomes available, so that aerobic respiration may occur

Question 19

Similarities between aerobic and anaerobic respiration

Answer 19

• glucose is the source of energy
• energy in the for of ATP is released
• the reactions are controlled by enzymes

Question 20

Differences between aerobic and anaerobic respiration

Answer 20

1. Presence of oxygen— absence of oxygen
2. Starts in cytosol and ends in mitochondria— occurs in cytocol
3. One glucose molecule releases 38ATPs(net)— one glucose molecule releases only 2ATPs(net)
4. ATP,CO² and water are products in plant and animal cells— ATP,CO² and ethanol are products in plant cells while ATP and lactic acid are products in animal cells