Bioenergetics 1

Question 1

What type of reaction is photosynthesis?

Answer 1

Photosynthesis is an endothermic reaction (because it takes in light energy)

Question 2

What is photosynthesis?

Answer 2

Photosynthesis is the process in which plants use to trap light energy.

Question 3

What is the function of the chlorophyll in the chloroplasts?

Answer 3

The function of the chlorophyll is to absorb light energy.

Question 4

What do chloroplasts contain?

Answer 4

Chloroplasts contain chlorophyll

Question 5

What is the equation for photosynthesis?

Answer 5

Carbon dioxide + water ➨ glucose + oxygen.

Question 6

The light energy taken in by the leaf is used to convert carbon dioxide and water into?

Answer 6

The light energy taken in by the leaf is used to convert carbon dioxide and water into glucose and oxygen.

Question 7

What are some of the things needed for photosynthesis to take place?

Answer 7

carbon dioxide, water, chlorophyll and sunlight

Question 8

What was the limiting factor if we increase the light intensity and the rate of photosynthesis also increases?

Answer 8

If we increase light intensity and the rate of photosynthesis also increases that tells us light intensity was the limiting factor.

Question 9

What happens if we keep increasing the light intensity? and what does this mean?

Answer 9

If we keep increasing the light intensity there comes a point where the rate of photosynthesis is no longer increasing. (levels of in a graph). This means light intensity is no longer the limiting factor. (something else is now in short supply for example water).

Question 10

What are the 5 uses of glucose produced from photosynthesis?

And what is your mnemonic to help you remember this?

Answer 10

The first use of glucose produced from photosynthesis is to release energy for respiration. The second use of glucose is it can be converted and stored as starch. The third use is to produce fats and oils. The fourth use is to make cellulose for the plant cell wall. The fifth use is to produce amino acids.

“SCARF”

Each letter represents the 5 different uses of glucose:

Starch – glucose can be converted and stored as starch
Cellulose – strengthens the plant cells wall
Amino acids – produce amino acids
Respiration – releases energy for respiration
Fat – produces fats and oils

Question 11

What happens to the leaf if we increase the temperature too much during photosynthesis?

Answer 11

If we increase the temperature too much then the enzymes in the leaf will start to denature and the rate of photosynthesis will fall.

Question 12

What type of reaction is respiration?

Answer 12

Respiration is an exothermic reaction because it releases energy (respiration takes place continuously in all living cells)

Question 13

What is the equation for aerobic respiration?

Answer 13

Glucose + oxygen ➨ carbon dioxide + water

Question 14

What is the equation for anaerobic respiration?

Answer 14

Glucose ➨ lactic acid

Question 15

What causes lactic acid to build up?

Answer 15

Shortage of oxygen causes lactic acid to build up.

Question 16

What happens to the glucose during anaerobic respiration?

Answer 16

During anaerobic respiration glucose is converted to lactic acid.

Question 17

What does anaerobic respiration not require that aerobic respiration does?

Answer 17

Anaerobic respiration does not require any oxygen.

Question 18

What is the equation for anaerobic respiration in yeast cells or in other words FERMANTATION?

Answer 18

Glucose ➨ ethanol + carbon dioxide

Question 19

What is anaerobic respiration in yeast cells called? and what is this reaction used for?

Answer 19

Anaerobic respiration in yeast cells is called fermentation and this reaction is used to make alcoholic drinks and bread.

Question 20

In which part of a cell does aerobic respiration occur?

Answer 20

Aerobic respiration occurs in the mitochondria.

Question 21

Why does respiration take place?

Answer 21

Respiration takes place in all living organisms to release energy for movement, growth and repair.

Question 22

Why is less energy released in anaerobic respiration?

Answer 22

Less energy is released in anerobic respiration as the glucose in anaerobic respiration is not completely oxidised.

Question 23

What’s an effect / symptom of lactic acid build up and what does it cause during exercise?

Answer 23

An effect / symptom of lactic acid build up is, it causes the muscles to become fatigued and this causes the muscles to stop contracting efficiently.

Question 24

What is aerobic respiration?

Answer 24

Aerobic Respiration is a chemical reaction which takes place in all livings cells and produces energy by using oxygen and releases energy from glucose.

Question 25

Where does anaerobic respiration take place?

Answer 25

Anaerobic respiration takes place in the cytoplasm.

Question 26

What is anaerobic respiration?

Answer 26

Anaerobic respiration is a process that allows cells to produce energy without oxygen but by breaking down sugars such as glucose.