Cellular respiration

Question 1

Law of conservation of energy

Answer 1

All energy on Earth and in the universe remains constant. It cannot be created or destroyed. All energy on earth originally comes from the sun

Question 2

Cell respiration

Answer 2

Process from releasing energy from an organic compound such as glucose

Question 3

Aerobic respiration

Answer 3

• oxygen must be present
• glucose gets broken down
• carbon dioxide and water are formed
• lots of energy is stored in the form of ATP
• respiration is catalysed by enzymes as without them, reactions would be too slow to produce enough energy to keep the organism alive

Question 4

Mitochondria

Answer 4

Site where cellular respiration occurs. Found in all living cells but number depends on energy requirements of cell. Active cells have lots of mitochondria

Question 5

ATP

Answer 5

Adenosine triphosphate and is the energy carrier of the cell. It consists of adenine, ribose sugar and three phosphates.

Question 6

ADP

Answer 6

Occurs when end phosphate in ATP is removed, therefore becoming Adenosine Diphosphate. Energy is released between the second and third phosphate. Known as the ENERGY ACCEPTOR

Question 7

Anaerobic respiration

Answer 7

Occurs when our cells do not get enough oxygen, meaning that the glucose in cells is broken down into lactic acid and a small amount of energy

Question 8

Oxygen debt

Answer 8

Caused by anaerobic respiration. Lactic acid diffuses into the blood and is detected by chemoreceptors in our brain. This stimulates our body to breathe more deeply and quickly so carbon dioxide is removed and oxygen is taken in (hence why we breathe heavily after exercise)

Question 9

Efficiency of anaerobic respiration

Answer 9

Not an efficient process due to the fact that
1. glucose is not completely broken down so only a small amount of energy is released for use in the cells leading to less ATP being formed
2. Lactic acid accumulates in cells as an end product of anaerobic respiration, it is toxic to the cells and has a paralysing effect on muscle

Question 10

Alcoholic fermentation

Answer 10

Anaerobic respiration that occurs in plants and micro-organisms. When glucose ferments (in absence of oxygen), ethanol, carbon dioxide and very small amounts o energy are released