Cell Biology Homework – Key Area Respiration
Homework Exercise 10 Respiration
1. The process of aerobic respiration in a cheek cell is shown
below.
Glucose
Stage 1
Product Y
Stage 2
Carbon dioxide
and Product X
(a) Name Stage 1.
(1)
(b) Where in the cell does Stage 1 occur?
(1)
(c) Name Product Y form Stage 1.
(1)
(d) ATP is formed during respiration and broken down for use in cells.
(i) How many molecules of ATP are formed from each glucose molecule
during each stage?
(e)
Stage 1 only ___________________
(1)
Stage 2 only __________________
(1)
Which gas must be available for stage 2 to occur?
(1)
(f) In which cell organelle does Stage 2 occur?
(1)
(g) Name Product X produced during Stage 2.
(1)
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Cell Biology Homework – Key Area Respiration
2. The experiment shown below was set-up to demonstrate aerobic respiration
in peas that are germinating (starting to grow) at a temperature of 15oC.
tap
tap
closed
closed
tube
tube
X
Y
Boiled and
Germinating
sterilised
peas
peas
Chemical to
Chemical to
absorb
carbon
dioxide
absorb carbon
Coloured
dioxide
liquid
After two days, the level of liquid had risen in the tube Y however there
was no change in the liquid level in tube X.
The higher the liquid rises the greater the rate of respiration.
(a) Explain the purpose of A as a control in this experiment.
(1)
(b)* Predict the effect on the level of the liquid in tube Y if a greater
mass of peas is used.
(1)
(c)* State the effect of increasing the temperature from 15oC to 25oC
on the rate of respiration.
(1)
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Cell Biology Homework – Key Area Respiration
3(a). Lactic acid is a waste product from one type of respiration. What
type of respiration produces lactic acid?
(1)
(b) The lactic acid content of the blood of a professional cyclist was
measured while cycling at different speeds.
The graph shows the results of these measurements taken at the start
of the racing season and at the end.
(i) What was the lactic acid concentration when the cyclist was travelling
at 15 miles per hour?
……………….nM
(1)
(ii) At the start of the season, what was the speed of the cyclist when he
was producing 50% of his maximum lactic acid concentration?
……………….. miles per hour
(1)
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Cell Biology Homework – Key Area Respiration
4. The following list contains some features of aerobic respiration and
fermentation in germinating peas.
List
W
Does not use oxygen
X
Produces carbon dioxide
Y
Yields a large amount of ATP per glucose molecule
Z
Produces ethanol
Copy and complete the table below by writing the letters from the list into the
correct columns.
Each letter may be used once or more than once.
Aerobic respiration in
Fermentation in
germinating peas
germinating peas
(4)
5. Complete the word equation for aerobic respiration.
Glucose + ________
ATP + ________+_________
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(2)