Bioenergetics

Question 1

Where does photosynthesis occur?

Answer 1

Chloroplasts

Question 2

What’s the balanced equation for photosynthesis?

Answer 2

6CO2 + H2O ————> C6H12O6 + 6O2

Question 3

What do plants use glucose for?

Answer 3

Respiration (for energy)
Making cellulose (to make cell walls)
Making amino acids (to make proteins)
Stored as oils and fats, lipids. 
Stored as starch (to use when photosynthesis can’t occur)

Question 4

What factors affect photosynthesis?

Answer 4

Light intensity
Temperature
CO2
Sometimes chlorophyll

Question 5

How can we measure the effect of light intensity on photosynthesis?

Answer 5

Set up a boiling tube containing of sodium hydrogencarbonate solution.
Cut a piece of the pondweed.
Place the pondweed in the boiling tube.
Position the pondweed 10 cm away from the boiling tube. Allow the boiling tube to stand for five minutes. Count the number of bubbles emerging in one minute.
Repeat the count five times and record your results.
Calculate the average number of bubbles produced per minute.
Repeat the experiment at different distances away from the light source.

Question 6

What e the link between light intensity and distance?

Answer 6

light intensity is inversely proportional to distance2

Question 7

Why are greenhouse useful?

Answer 7

It can create conditions for farming.
You can control temperature inside with a heater or shaded/ventilator, light by using artificial light, carbon dioxide by using a paraffin heater, and keep plants free from diseases.
A downside is it’s expensive.

Question 8

What’s respiration?

Answer 8

The process of transferring energy from glucose

Question 9

What’s the energy used for?

Answer 9

Building larger molecules
Allows muscles to contract (animals)
Keep body temperature constant (animals and birds)

Question 10

What’s metabolism?

Answer 10

All the chemical reactions in the cells of an organism.

Question 11

Give an example of larger molecules being made from small ones.

Answer 11

Lots of small glucose molecules can form starch, glycogen, and cellulose when joined together.

Question 12

Give an example of large molecules being broken down into smaller ones.

Answer 12

Excess protein is broken down to produce urea

Question 13

What are the two tires of respiration?

Answer 13

Anaerobic and aerobic

Question 14

What’s the difference between anaerobic respiration and aerobic respiration?

Answer 14

Aerobic respiration uses oxygen whilst anaerobic is without oxygen.

Question 15

What’s the word equation for aerobic respiration?

Answer 15

glucose + oxygen ——> carbon dioxide + water

Question 16

What’s the word equation for anaerobic respiration?

Answer 16

glucose ———> lactic acid

Question 17

When do you use anaerobic respiration?

Answer 17

When your body can’t supply enough oxygen to your muscles.

Question 18

What’s anaerobic respiration called in yeast cells and what’s the word equation?

Answer 18

Fermentation

glucose ——-> ethanol + carbon dioxide

Question 19

What happens when you exercise?

Answer 19

Your muscles contract more frequently so you need more energy, which comes from increased respiration. But we also need more oxygen so our breathing rate, breathing volume and heart rate all increase to take more oxygen and get it around the body faster.

If the exercise is very vigorous, you’ll start breathing anaerobically but it causes lactic acid in your muscles, causing pain. When you’re done exercising, you’ll have an oxygen debt

Question 20

What’s oxygen debt?

Answer 20

The amount of extra oxygen needed to react it with the lactic acid and remove it from the cells. (it produces carbon dioxide and water)