Bioenergetics- Photosynthesis

Question 1

Photosynthesis transfers _____ energy into ________ energy inside plants.

Answer 1

Photosynthesis transfers light energy into chemical energy inside plants.

Question 2

Photosynthesis is an ____________ reaction.

Answer 2

Photosynthesis is an endothermic reaction.

Question 3

The reactants in photosynthesis are ______ _______ and _____.

Answer 3

The reactants in photosynthesis are carbon dioxide and water.

Question 4

The products of photosynthesis are _______ and ______.

Answer 4

The products of photosynthesis are glucose and oxygen.

Question 5

What is the chemical symbol for Carbon Dioxide?

Answer 5

Carbon dioxide - CO2

Question 6

What is the chemical symbol for Water?

Answer 6

Water - H2O

Question 7

What is the chemical symbol for Oxygen?

Answer 7

Oxygen - O2

Question 8

What is the chemical symbol for Glucose?

Answer 8

Glucose - C6H12O6

Question 9

Glucose made in photosynthesis is used for: production of c_______ c___ w____, producing a____ a____, producing f___ and o___ and can be stored as i_________ s_____.

Answer 9

Glucose made in photosynthesis is used for: production of cellulose cell walls, producing amino acids, producing fats and oils and can be stored as insoluble starch.

Question 10

The rate of photosynthesis can be affected by: c_____ d______ concentration, _____ intensity, t__________ and the amount of c_________.

Answer 10

The rate of photosynthesis can be affected by: carbon dioxide concentration, light intensity, temperature and the amount of chlorophyll.

Question 11

Limiting factors for photo synthesis are important to the _________ of growing in greenhouses.

Answer 11

Limiting factors for photo synthesis are important to the economics of growing in greenhouses.

Question 12

Limiting factors interact to gain maximum ______ ____ and ______.

Answer 12

Limiting factors interact to gain maximum growth rate and profit.

Question 13

where does photosynthesis take place

Answer 13

inside the leaves of the plant where the chloroplasts are found

Question 14

required practical - photosynthesis

Answer 14

1. take a boiling tube and place it 10cm away from an LED light source
2. fill the boiling tube with sodium hydrogen carbonate solution.
3. place a piece of pond weed into the boiling tube and cut the top off
4. leave for 5 minutes to allow pond weed to acclimatize
5. start a stop watch and count the number of bubbles produced in one minute
6. repeat two more times and calculate the mean number of bubbles
7. repeat experiment from the start but do it at 20cm, then 30, then 40

Question 15

why is an LED light source used

Answer 15

it doesn’t change the temperature of the experiment

Question 16

what are the two main problems with this practical

Answer 16

bubbles can be too fast to count accurately
bubbles are not always the same size meaning a large bubble would be the same as a small

Question 17

How can you overcome these problems

Answer 17

by measuring the volume of oxygen produced

Question 18

explain the practical again whilst improving the problems

Answer 18

place the pondweed under a funnel and catch the bubbles in a measuring cylinder filled with water

Question 19

when producing a graph after this experiment what’s the key point and what is it called

Answer 19

if we double the distance, then the number of bubbles per minutes falls by a factor of 4. This is known as the inverse - square law

Question 20

what’s the reason for the inverse - square law

Answer 20

If we double the distance, the light intensity falls by four times and because we need light for photosynthesis that also causes the number of oxygen bubbles to fall by four times