Cambridge IGCSE™
GE S
Biology SA M
PL
E
PA
WORKBOOK
Mike Smith and Heidi Foxford
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Contents
Contents Section 1: Characteristics and classification of living organisms Characteristics of living organisms Concept and uses of classification systems Features of organisms
x x x x
Section 2: Organisation of the organism Cell structure Size of specimens
x x x
Section 3: Movement into and out of cells x Diffusion x Osmosis x Active transport x
GE S
Section 4: Biological molecules Biological molecules
x x
x Section 5: Enzymes Enzymes x
PA
x Section 6: Plant nutrition Photosynthesis x x Leaf structure
SA M
PL
E
Section 7: Human nutrition x Diet x x Digestive system x Physical digestion Chemical digestion x Absorption x Section 8: Transport in plants x Xylem and phloem x x Water uptake Transpiration x Translocation x x Section 9: Transport in animals Circulatory systems x Heart x x Blood vessels Blood x Section 10: Diseases and immunity Diseases and immunity
x x
Section 11: Gas exchange in humans Gas exchange in humans
x x
Section 12: Respiration x Respiration x Aerobic respiration x
3
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Contents
Anaerobic respiration
x
Section 13: Excretion in humans Excretion in humans
x x
Section 14: Coordination and response x Coordination and response x x Sense organs Hormones x Homeostasis x Tropic responses x Section 15: Drugs x Drugs x
GE S
Section 16: Reproduction Asexual reproduction Sexual reproduction Sexual reproduction in plants Sexual reproduction in humans Sexual hormones in humans Sexually transmitted infections
x x x x x x x
PL
E
PA
Section 17: Inheritance x x Chromosomes, genes and proteins Mitosis x Meiosis x Monohybrid inheritance x
SA M
Section 18: Variation and selection x Variation x Adaptive features x Selection x Section 19: Organisms and their environment x x Energy flow Food chains and food webs x Nutrient cycles x Populations x Section 20: Human influences on ecosystems x Food supply x Habitat destruction x Pollution x Conservation x Section 21: Biotechnology and genetic modification x Biotechnology and genetic modification x Biotechnology x Genetic modification x
Answers for all the questions in this Workbook are available from http://www.collins.co.uk/internationalresources. 4
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Section 1: Characteristics and classification of living organisms | Characteristics of living organisms
Characteristics of living organisms Student’s Book pages 11–13 | Syllabus learning objectives 1.1.1
1
a
The boxes on the left below show some of the characteristics of living organisms.
The boxes on the right show some descriptions of characteristics.
GE S
Draw lines to link each characteristic to its description. Draw four lines. characteristic
description
ability to detect and respond to changes in the environment
PA
movement
breakdown of nutrient molecules to release energy
PL
E
reproduction
SA M
respiration
change of position or place
increase in size or dry mass making more of the same kind of organism
sensitivity
[4 ] b
Circle the characteristics that are shown by all living organisms. digestion nutrition
excretion
photosynthesis
growth sight
transpiration
[3 ]
5
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Section 1: Characteristics and classification of living organisms | Concept and uses of classification systems
Concept and uses of classification systems Student’s Book pages 13–18 | Syllabus learning objectives 1.2.1–1.2.4; SUPPLEMENT 1.2.5–1.2.7
1
a
Fig. 1.1 shows part of a dichotomous key.
GE S
It can be used to identify some different African mammals.
PA
Complete the key by writing suitable questions in the three boxes.
no
E
yes
SA M
PL
giraffe
yes
no
elephant
yes zebra
Fig. 1.1
no lion
[3 ]
6
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S
Section 1: Characteristics and classification of living organisms | Concept and uses of classification systems
b
Complete the sentences about lions using words from the list. Each word can be used once, more than once or not at all. binomial classification genus international organism species
African lions have the scientific name Panthera leo. This name is also known as a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ........
name because it is made up of two parts. The first
part, Panthera, is the . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................................................... name. The second part, leo, is the . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................. name.
GE S
African lions are very similar to Asiatic lions found in Asia. Asiatic lions also have the scientific name Panthera leo. This means that Asiatic and African lions are the same species. One reason that scientists have decided that the lions are the same species is because they have compared DNA from Asiatic and African lions.
PA
c
[ 3]
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...............................................................................................................................................
PL
1
E
Suggest two other reasons why scientists have decided that African and Asiatic lions are the same species.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
2
SA M
s
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...............................................................................................................................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
d SUPPLEMENT
[2 ]
European cave lions, Panthera spelaea, became extinct about 13 000 years ago. i Explain what this scientific name shows about the evolutionary relationship between European cave lions, African lions and Asiatic lions.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................................................................................................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................................................................................................................
[2 ]
7
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Section 1: Characteristics and classification of living organisms | Features of organisms
ii Explain how scientists could use DNA to confirm the evolutionary relationship between European cave lions, African lions and Asiatic lions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................................................................................................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...............................................................................................................................................
[2 ]
TIP
GE S
If a question has 2 marks, try to make at least two distinct points in your answer.
Features of organisms
2
Which statement describes plants but not animals? Circle your answer.
SA M
1
PL
E
PA
Student’s Book pages 19–32 | Syllabus learning objectives 1.3.1–1.3.3; SUPPLEMENT 1.3.4–1.3.7
A
cells usually contain a nucleus
B
made of many cells
C
make food by photosynthesis
D
need to find food to eat
[1 ]
Which statement describes animals but not plants? Circle your answer. A
cells have a cell wall
B
made of many cells
C
make food by photosynthesis
D
usually able to move from one place to another
[1 ]
8
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Section 1: Characteristics and classification of living organisms | Features of organisms
3
Place ticks (✓) in the table to identify the feature or features of each vertebrate group listed. Each row may contain one or more ticks. Vertebrate group Feature
Amphibians
Birds
Fish
Mammals
Reptiles
Dry scaly skin External fertilisation
GE S
Feathers Fur or hair
PA
Wet scales
PL
Fig. 1.2 shows three different arthropods. Choose a name from the list to identify the group to which each arthropod belongs.
SA M
4
E
[6 ]
arachnid crustacean insect myriapod Write the names of the groups on the lines in Fig. 1.2.
............................................................................
............................................................................
............................................................................
Fig. 1.2 [3 ]
9
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Section 1: Characteristics and classification of living organisms | Features of organisms
5 SUPPLEMENT
Most members of the prokaryote and protoctist kingdoms are single-celled organisms. State two differences between single-celled prokaryotes and protoctists.
1
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...............................................................................................................................................
2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...............................................................................................................................................
[2 ]
TIP In answers, be clear what you are writing about; try not to refer to just ‘it’ or ‘they’. In question 5, make it clear whether you are referring to prokaryotes or protoctists.
SUPPLEMENT
Fig. 1.3 shows three different plants. Choose a name from the list to identify the group to which each plant belongs.
GE S
6
PA
dicotyledon fern monocotyledon
SA M
PL
E
Write the names of the groups on the lines in Fig. 1.3.
............................................................................
............................................................................
............................................................................
Fig. 1.3
[2 ] 7 SUPPLEMENT
There are many different types of virus. However, they all have the same simple structure. Describe the simple structure of a virus.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................................................................................................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................................................................................................................
[2 ]
10
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Section 2: Organisation of the organism | Cell structure
Cell structure Student’s Book pages 41–51 | Syllabus learning objectives 2.1.1–2.1.7
1
Fig. 2.1 shows a plant cell. cell membrane mitochondria
W X
chloroplast Y
ribosome
a
PA
Fig. 2.1
State the names of structures W, X, Y and Z in Fig 2.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
X
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
.................................................................................................
Z
.................................................................................................
PL
SA M
[4 ]
.................................................................................................
[3 ]
Identify three structures shown in Fig. 2.1 that are not found in animal cells.
1
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .....
2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .....
c
Y
E
W
b
GE S
Z
3
Describe the functions of the following cell structures. cell membrane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................................................................................................................................... mitochondria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................................................................................................................................... ribosomes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................................................................................................................
d
[3 ]
State the name of one structure found in bacterial cells that is not shown in Fig. 2.1.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
[1 ]
11
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Section 2: Organisation of the organism | Size of specimens
2
Complete the sentences about cells using words from the list. Each word can be used once, more than once or not at all. divide grow organisms organs specialise tissues
New cells are formed when existing cells .................................................................................................... . Similar cells are grouped together to form .................................................................................................... . 3
[2 ]
State the functions of the following specialised cells:
neurone . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..............
[3 ]
PA
red blood cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................
GE S
palisade mesophyll cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .....................................................
PL
E
Size of specimens
SA M
Student’s Book pages 52–53 | Syllabus learning objectives 2.2.1–2.2.2; SUPPLEMENT 2.2.3
1
a
Complete the formula for magnification.
magnification = _________________
[2 ]
12
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Section 2: Organisation of the organism | Size of specimens
b
A student uses a microscope to take an image of a cell. The length of the cell image is 60 mm. The magnification of the image is ×200.
GE S
Calculate the actual length of the cell in mm.
c
mm
[3 ]
PA
....................................................................................................
Give the actual length of the cell in micrometres ( μm).
SA M
PL
E
SUPPLEMENT
....................................................................................................
[1 ]
µm TIP
When doing a calculation, always show your working. That way, even if your final answer is incorrect, you may still gain some marks.
13
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Section 3: Movement into and out of cells | Diffusion
Diffusion Student’s Book pages 61–65 | Syllabus learning objectives 3.1.1–3.1.5
1
Which statement describes diffusion? Circle your answer. A Net movement of particles from a region of high concentration to another region of high concentration.
GE S
B Net movement of particles from a region of high concentration to a region of low concentration. C Net movement of particles from a region of low concentration to another region of low concentration.
Define the term net movement.
PL
2
[1 ]
E
PA
D Net movement of particles from a region of low concentration to a region of high concentration.
SA M
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................................................................................................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................................................................................................................
3
[1 ]
What provides the energy for diffusion? Circle your answer. A
energy from respiration
B
energy from sunlight
C
enzyme activity
D
kinetic energy
[1 ]
14
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Section 3: Movement into and out of cells | Diffusion
4
Describe the importance of the diffusion of oxygen in animals.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
5
[3 ]
Some students investigate diffusion using the apparatus shown in Fig. 3.1.
They cut a small cube of beetroot of size 1 cm3, which they wash and then place in clean water.
GE S
As the coloured substance diffuses out of the beetroot, it turns the water pink.
PA
The students time how long it takes to turn the water a certain shade of pink. This indicates the rate of diffusion. beaker water
E
cube of beetroot
PL
Fig. 3.1
SA M
The students want to investigate how surface area affects the rate of diffusion. They do this by repeating the experiment several times. Each time they start with a fresh 1 cm3 cube of beetroot, but cut each cube into a different number of smaller pieces. a
Identify two variables the students should control.
1
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................................................................................................................
2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................................................................................................................................................
b
Suggest one way the students can make sure the water is the same shade of pink each time when they stop timing.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
c
[2 ]
[1 ]
Suggest the conclusion that the students will make from their results.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
[1 ] 15
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Section 3: Movement into and out of cells | Osmosis
Osmosis Student’s Book pages 66–73 | Syllabus learning objectives 3.2.1–3.2.6; SUPPLEMENT 3.2.7–3.2.9
1
Complete the sentences about water using words from the list. Each word can be used once, more than once or not at all. digestion impermeable osmosis permeable
GE S
solute solution solvent transport Water acts as a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................... in the body, allowing the movement of dissolved substances, for example during the .................................................................................................... of
PA
substances through the blood.
E
Water diffuses in and out of cells by . . . . . . . . . . . . . ....................................................................................... through their [4 ]
Fig. 3.2 shows two images of the same plant. One image shows the plant after it has not been watered for two weeks. The other image shows the plant after it has been watered regularly.
SA M
2
PL
partially . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............. membranes.
after no watering for two weeks
after regular watering
Fig. 3.2
16
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Section 3: Movement into and out of cells | Osmosis
Explain why watering the plant affects its appearance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
3
[3 ]
Some students investigated osmosis. They cut identical blocks from a potato and measured their lengths. They left the blocks in three different solutions as shown in Fig. 3.3. After 30 minutes, they removed the blocks and measured their lengths again. dilute sugar solution
water
GE S
concentrated sugar solution
PA
potato block
E
Fig. 3.3
a
SA M
PL
The students found that one block increased in length, one decreased and one stayed the same. Place ticks (✓) in the table to show their results.
Place one tick in each row.
Increased in length
Decreased in length
Stayed the same length
Concentrated sugar solution Dilute sugar solution Water
[2 ]
17
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Section 3: Movement into and out of cells | Osmosis
b
Apart from the length of the potato blocks, state one other feature that the students could have measured to show the effects of different concentrations.
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4
[1 ]
Some investigations of osmosis involve dialysis tubing.
It has variable permeability.
B
It is fully permeable.
C
it is impermeable.
D
It is partially permeable.
[1 ]
PA
5
A
GE S
Which property makes dialysis tubing suitable for investigations of osmosis? Circle the correct answer.
Define osmosis. Refer to water potential in your answer.
PL
E
SUPPLEMENT
SA M
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[3 ]
Fig. 3.4 shows a turgid plant cell. In the space alongside, draw the same cell when it SUPPLEMENT is plasmolysed. 6
cell wall cell membrane vacuole cytoplasm
turgid cell
plasmolysed cell
Fig. 3.4 [2 ] 18
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Section 3: Movement into and out of cells | Active transport
7
Red blood cells can be stored for use in blood transfusions. The cells are stored in a sodium chloride solution that has the same water potential as that inside healthy red SUPPLEMENT blood cells. Explain why it is important that the sodium chloride solution has the same water potential as healthy red blood cells. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................................................................................................................................
Active transport
[2 ]
GE S
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PL
E
PA
Student’s Book pages 73–74 | Syllabus learning objectives 3.3.1; SUPPLEMENT 3.3.2–3.3.3
Describe two ways in which the process of active transport is different from diffusion.
1
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SA M
1
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2
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[2 ]
TIP Make sure that your answer is as clear as possible. Try to write ‘active transport’ or ‘diffusion’ instead of ‘it’ so that there is no confusion about what you are referring to.
19
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Section 3: Movement into and out of cells | Active transport
2
The root hair cells of plants use active transport to take in mineral ions from the soil.
SUPPLEMENT
Explain why root hair cells need to use active transport to take in mineral ions from the soil.
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3
[2 ]
State the role of protein carriers in active transport.
SUPPLEMENT
[1 ]
SA M
PL
E
PA
GE S
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20
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