4.4 Bioenergetics

Question 1

What is the word equation for photosynthesis?

Answer 1

Carbon dioxide + water —-> glucose + oxygen

Question 2

What type of reaction in photosynthesis?

Answer 2

Endothermic

Question 3

During photosynthesis what is the energy from sunlight converted to?

Answer 3

Chemical energy in the form of glucose molecules

Question 4

What factors affect photosynthesis?

Answer 4

Temperature
Carbon dioxide concentration
Light intensity
Chlorophyll concentration

Question 5

How does temperature affect rate of photosynthesis?

Answer 5

Increase temp mean increased rate. This is because more energy is provided for the reaction. As the temperature reaches 45 degrees the rate of photosynthesis drops to zero because the enzymes become denatured

Question 6

How does carbon dioxide levels affect the rate of photosynthesis?

Answer 6

As carbon dioxide increase so does the rate

This is because carbon dioxide is needed in the reaction

After a certain point it is no longer the limiting factor

Question 7

How does light intensity affect rate of photosynthesis?

Answer 7

As light intensity increases, so does the rate

More energy is provided for the reaction

Question 8

How does chlorophyll concentration affect rate of photosynthesis?

Answer 8

As it decrease so does rate

Less light can be trapped

Question 9

What is it called when you double the distance between lamp and pondered and the light intensity reduces by a quarter?

Answer 9

Inverse square law

Question 10

What can the glucose produced in photosynthesis be used for?

Answer 10

Used for respiration
Converted into insoluble starch for storage
Used to produce fat or oil for storage
Used to produce cellulose which strengthens cell walls
Used to produce amino acids for protein synthesis

Question 11

What type of reaction is respiration?

Answer 11

Exothermic

Question 12

What does respiration do?

Answer 12

Releases energy from glucose molecules for use by the body

Question 13

Why do organisms need the energy released during respiration?

Answer 13

Chemical reactions to build larger molecules

For movement

To keep warm

Question 14

Respiration in cells can be __________ (with oxygen) or _____________ (without oxygen)

Answer 14

Aerobic

Anaerobic

Question 15

What is the word equation for aerobic respiration?

Answer 15

Glucose + oxygen —–> carbon dioxide + water

Question 16

In aerobic respiration, what is not fully broken down?

Answer 16

Glucose

Question 17

Energy transfer is much ________ in anaerobic respiration than aerobic respiration

Answer 17

Less

Question 18

What is the word equation for the anaerobic respiration that occurs in animals?

Answer 18

Glucose —–> lactic acid

Question 19

What is the word equation for anaerobic respiration in plants and yeast?

Answer 19

Glucose —-> ethanol+ carbon dioxide

Question 20

What is anaerobic respiration in yeast called?

Answer 20

Fermentation

Question 21

What is anaerobic respiration important for in manufacturing?

Answer 21

Bread and alcoholic drinks

Question 22

What does the body demand more during exercise?

Answer 22

More energy

Question 23

During exercise the body demands more energy. So what happens?

Answer 23

Rate of respiration increases

Question 24

What all increase when the respiration rate increases?

Answer 24

Heart rate
Breathing rate
Breath volume

Question 25

Why do Heart rate, Breathing rate and Breath volume all increase during exercise?

Answer 25

To supply the muscles with more oxygen and glucose for the increase in aerobic respiration

Question 26

When does anaerobic respiration start to happen?

Answer 26

During vigorous activity when the muscle are not getting enough oxygen

Question 27

What does anaerobic respiration cause in the body?

Answer 27

Build up of lactic acid and creates oxygen debt

Question 28

What does the build up of lactic acid cause in the body?

Answer 28

Muscles to hurt and stops them contracting efficiently

Question 29

Why does lactic acid need getting rid of quickly?

Answer 29

It is poison

Question 30

Once exercise is finished, the oxygen debt must be __________

Answer 30

'Repaid'

Question 31

What happens to the lactic acid after exercise?

Answer 31

Blood flowing through muscles transports the lactic acid to the liver where it is broken down

Question 32

What is oxygen debt?

Answer 32

The amount of extra oxygen the body needs after exercise to react with the lactic acid and remove it from cells

Question 33

What is metabolism?

Answer 33

The sum of all the chemical reactions in a cell or in the body

Question 34

What are the chemical reaction in a cell or body controlled by?

Answer 34

Enzymes and many need a transfer of energy

Question 35

What is the energy in respiration used for in metabolism?

Answer 35

Energy is transferred by respiration and used to make new molecules

Question 36

What is the energy transferred by respiration used to build specifically?

Answer 36

The conversion of glucose to starch, glycogen and cellulose Formation of lipid molecules from a molecule of glycerol and three molecules of fatty acids The use of glucose and nitrate ions to form amino acids, which are used to synthesise proteins The breakdown of excess proteins into urea for excretion