Bioenergetics

Question 1

What do plants use photosynthesis for?

Answer 1

To trap light energy

Question 2

What type of reaction is photosynthesis?

Answer 2

Endothermic

Question 3

What chemical within a leave allows it to absorb light?

Answer 3

Chlorophyll

Question 3

Where does photosynthesis take place?

Answer 3

In the chloroplasts in the leaves of a plant

Question 4

What is the word equation for photosynthesis?

Answer 4

carbon dioxide + water → glucose + oxygen

Question 5

What is the symbol equation for photosynthesis?

Answer 5

6CO2 + 6H2O → C6H12O6 + 6O2

Question 6

How would we know if light intensity was the limiting factor of photosynthesis?

Answer 6

If increasing the light intensity also increased the rate of reaction

Question 6

How does the amount of light and carbon dioxide affect the rate of photosynthesis?

Answer 6

The more light and carbon dioxide, the faster the reaction

Question 7

How would we know when light intensity was no longer the limiting factor?

Answer 7

When the rate of photosynthesis stops increasing in correlation with the added light intensity.

Question 8

Other than light intensity, what are the possible limiting factors of photosynthesis?

Answer 8

Carbon dioxide, temperature, chlorophyll

Question 9

What affects the amount of chlorophyll in a plant

Answer 9

Disease like tobacco mosaic virus and environmental stress like lack of nutrients

Question 10

What do plants use glucose for

Answer 10

Respiration, making cellulose, making proteins by making amino acids, storing it as fats and starch

Question 11

At what temperature do the enzymes needed for photosynthesis denature

Answer 11

About 45 degrees celsius

Question 12

What does the inverse square law state?

Answer 12

Light intensity decreases in the proportion to the square of the distance

Question 13

What is the equation of the inverse square law?

Answer 13

Light intensity is proportional to 1/distance^2

Question 14

How do greenhouses work?

Answer 14

They trap the sun’s heat meaning the temperature is not the limiting factor. Heaters can be added in the winter and blinds and ventilators in the summer (so the enzymes aren’t denatured)

Question 15

How do farmers increase light?

Answer 15

Using artificial lights after the sun goes down

Question 16

How do farmers increase carbon dioxide?

Answer 16

Using paraffin heaters - paraffin makes carbon dioxide as it burns

Question 17

What is respiration?

Answer 17

The process of transferring energy from the breakdown of sugar

Question 17

Where and when does respiration take place?

Answer 17

In every cell in the body all of the time

Question 18

What type of reaction is respiration?

Answer 18

Exothermic

Question 19

How do organisms use the energy they get from respiration?

Answer 19

To build large molecules from small ones (e.g. amino acids -> proteins), for muscle contractions, in mammals and birds to keep the body temperature steady

Question 20

What are some examples of smaller molecules forming large ones?

Answer 20

Glucose turning into: starch (stored in plant cells), glycogen (stored in animal cells) and cellulose (strengthens plant cell walls)

Question 21

How are proteins formed?

Answer 21

Glucose reacts with nitrate ions to make amino acids which join together to make proteins

Question 22

What is metabolism?

Answer 22

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

Question 22

What are some examples of larger molecules being broken down into smaller ones?

Answer 22

Glucose is broken down in respiration

Question 23

What is aerobic respiration?

Answer 23

respiration using oxygen - most efficient way to release energy from glucose

Question 24

Where does aerobic respiration take place?

Answer 24

In the mitochondria

Question 25

What is the word equation for aerobic respiration?

Answer 25

glucose + oxygen -> carbon dioxide + water

Question 25

What is the word equation for anaerobic respiration in animals?

Answer 25

Glucose -> Lactic Acid

Question 26

What is the symbol equation for aerobic respiration?

Answer 26

C6H12O6 + 6O2 -> 6CO2 + 6H2O

Question 27

When does anaerobic respiration take place?

Answer 27

When the body can’t supply enough oxygen to the muscles during vigorous exercise

Question 28

What is anaerobic respiration?

Answer 28

Respiration without oxygen. The incomplete breakdown of glucose, making lactic acid

Question 29

What is anaerobic respiration in yeast cells called?

Answer 29

Fermentation - It’s used in bread and alcoholic drinks like beer and wine

Question 30

What is the equation for anaerobic respiration in plants?

Answer 30

Glucose -> Ethanol + Carbon Dioxide

Question 31

Why does breathing rate increase during exercise?

Answer 31

To get more oxygen in the blood.

Question 32

Why does the heart rate increase when exercising?

Answer 32

To get the oxygenated blood around the body faster and remove carbon dioxide quicker

Question 33

What is oxygen debt?

Answer 33

The amount of extra oxygen the body needs to react with the lactic acid from anaerobic respiration to remove it, forming carbon dioxide and water

Question 34

How does the liver help remove lactic acid?

Answer 34

The blood that enters the muscles transports the lactic acid to the liver which converts it to glucose