Topic 5: photosynthesis

Question 1

describe the function of a chloroplast

Answer 1

where photosynthesis ocuurs
-thykaloid discs containing chlorophyll absorb light to produce carbohydrates and sugars

Question 2

features of chloroplasts

Answer 2

-Features of chloroplasts –> starch grain, ribosomes (70S), outer and inner membrane, stroma, thykaloid, granum

Question 3

thykaloid

Answer 3

Thykaloid –> contains chlorophyll and absorbs light

Question 4

starch grain

Answer 4

Starch grain –> stores polymers of glucose

Question 5

lamellae

Answer 5

Lamellae –> proteins that hold granum in optimum position to absorb light

Question 6

absorbance and reflection by chlorophyll

Answer 6

Chlorophyll reflect green light and absorbs all other colours such as red

Accessory pigment –> maximize the amount of pigment that can be absorbed e.g carotenoids

-chlorophyll is a mixture of pigments each absorbing different wavelengths of light

Question 7

Describe how you would present the data in the table as a graph

Answer 7

discrete data (distinct groups) = bar chart with standard deviation lines

Question 8

In leaves at the top of trees in a forest. CO2 is often the limiting factor for photosynthesis. Explain why

Answer 8

-light = not limiting as there is now shading
-temperature = not limiting as no shading (fast reactions of enzymes in LDR)