Bioenergetics

Question 1

What is photosynthesis?

Answer 1

An endothermic reaction in which energy is transferred to chloroplasts from the environment by light

Question 2

What is the word equation for photosynthesis?

Answer 2

Carbon dioxide + water > glucose + oxygen

Question 3

What is the formula equation for photosynthesis?

Answer 3

6CO2 + 6H2O > C6H12O6 + 6O2

Question 4

What are the 4 uses of glucose in plants?

Answer 4

1: respiration - energy is transferred from glucose
2: strengthening cell walls - glucose is converted into cellulose, which is used to make strong cell walls
3: protein synthesis - glucose and nitrate ions (from soil) are used to make amino acids, which are then made into proteins
4: energy storage - glucose is turned into lipids or insoluble starch to store energy

Question 5

How do you increase the rate of photosynthesis?

Answer 5

1: light intensity
2: temperature
3: CO2 concentration
4: amount of chlorophyll
Any of these factors can become the limiting factor (thing that stops photosynthesis happening any faster)

Question 6

What is the inverse square law?

Answer 6

Light intensity [weird alpha symbol] 1/distance (d)^2

Question 7

What 4 things are in a greenhouse to control limiting factors?

Answer 7

1: heaters (paraffin ones for CO2)
2: shades
3: lamps
4: ventilation

Question 8

What is respiration?

Answer 8

The process of transferring energy from glucose. It’s an exotérmica reaction that goes on continuously in living cells

Question 9

what 3 things is respiration used for?

Answer 9

1: to contract muscles for movement
2: to keep warm (in mammals and birds)
3: to build up larger molecules from smaller ones

Question 10

What is the word equation for aerobic respiration?

Answer 10

Glucose + oxygen > carbon dioxide + water

Question 11

What is the formula equation for aerobic respiration?

Answer 11

C6H12O6 + 6O2 > 6CO2 + 6H20

Question 12

What is anaerobic respiration?

Answer 12

Respiration without oxygen
It transfers much less energy than aerobic respiration because glucose isn’t fully oxidised

Question 13

What is anaerobic respiration in muscle cells?

Answer 13

Glucose > lactic acid

Question 14

What is anaerobic respiration in plant and yeast cells?

Answer 14

Glucose > ethanol + carbon dioxide

Question 15

What is anaerobic respiration called in yeast cells?

Answer 15

Fermentation

Question 16

What is metabolism?

Answer 16

The sum of all the reactions that happen in a single cell or the body.
Metabolic reactions use energy from respiration to make new molecules

Question 17

What are 3 metabolic reactions?

Answer 17

1: Glucose and nitrate ions combines to make amino acids, then made into proteins
2: Lipids broken down into glycerol and fatty acids
3: glucose molecules joined together to make bigger carbohydrates (eg, starch or glycogen)

Question 18

What are the effects or exercise on the body?

Answer 18

Exercise > more energy needed > more aerobic respiration needed > more oxygen needed

Question 19

What 3 things can be increased to get more oxygen into the body?

Answer 19

1: heart rate
2: breathing rate
3: breath volume

Question 20

What is oxygen debt?

Answer 20

The amount of extra oxygen needed to react with built-up lactic acid and remove it from cells.
During vigorous exercise, not enough oxygen is supplied to the muscles.

Question 21

What does not getting enough oxygen to the muscles mean?

Answer 21

Anaerobic respiration takes place in muscles > lactic acid builds up in muscles > oxygen debt created > heart rate and breathing rate stay high after exercise to repay oxygen debt

Question 22

How does the liver help with oxygen debt?

Answer 22

Blood goes to the muscle, takes out the lactic acid, returns to the liver. In the liver the lactic acid is converted into glucose.