Homework 2
1 (a). Colour code/label the equation to show the raw materials, essential
requirements and products of the reaction. (3)
Light
Carbon Dioxide + Water
Glucose + Oxygen
Chlorophyll
(b) Give 3 fates of the sugar produced in photosynthesis.
_________________________________________
_________________________________________
_________________________________________ (3)
(c) What are the 3 limiting factors of photosynthesis?
_________________________________________
_________________________________________
_________________________________________ (3)
2. Copy and complete the note by underlining the correct option in brackets:
The first stage of photosynthesis is {the light reactions/carbon fixation}
and takes place in the {mitochondrion/chloroplast}. {Light/Chemical}
energy is trapped by chlorophyll and converted into {light/chemical}
energy in the form of ATP. Water is split into hydrogen and {carbon
dioxide/oxygen}. The second stage of photosynthesis is
{photolysis/carbon fixation} which is the production of glucose when ATP,
hydrogen and {carbon dioxide/oxygen} react with many enzymes.
(7)
3. The table shows the monthly rainfall and rate of photosynthesis (measured
as the dry mass of leaf discs) of a West Lothian town.
Month
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Rainfall (cm)
20
14
12
10
8
5
3
4
8
14
19
20
Dry mass of leaf discs (g)
2.5
3.0
3.5
4.0
4.0
4.5
5.0
5.0
4.5
4.0
3.0
2.0
(a) Calculate the average dry mass of leaf discs per month.
Working:
Average: ___________ (1)
(b) Name the 3 driest months of the year.
_____________________________________
_____________________________________
_____________________________________ (3)
(c) How many months were wetter than April?
_____________________________________ (1)
Total =
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