B4%20Revision

1
B4 Revision
113 Questions

• GCSE Gateway Biology B

2
Contents
1. Who planted that there? 10 questions
2. Water, water everywhere 19 questions
3. Transport in plants 10 questions
4. Plants need minerals too 19 questions
5. Energy flow 16 questions
6. Farming 22 questions
7. Decay 9 questions
8. Recycling 8 questions
3
Who Planted That There?

• Chapter 1

10 Questions
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4
Question 1
Identify the parts of a plant cell
?
Cell wall
?
Cytoplasm
?
Cell membrane
?
Nucleus
?
Vacuole
Chloroplasts
?
5
Question 2
What is the role of chloroplasts?
To absorb light energy for photosynthesis
6
Question 3
Where does photosynthesis mainly occur?
In the leaves
7
Question 4
What 2 things are needed for photosynthesis?
Water thought the roots Carbon dioxide through
leaf pores
8
Question 5
What is given out by photosynthesis?
Oxygen through leaf pores
9
Question 6
?
?
Locate the parts of a leaf
?
?
?
?
?
?
?
?
?
10
Question 7

1. Broad, so large surface area
2. Thin, so short distance for gases to travel
3. Contain chlorophyll to absorb light
4. Have a network of veins for support and transport
5. Stomata for gas exchange

How are leaves adapted to photosynthesis?
11
Question 8
The exchange of gases in the stomata is by ?
Diffusion
12
Question 9
How is the structure of a leaf palisade cell
related to its function?
It contains many chloroplasts
13
Question 10
How is the cellular structure of a leaf adapted
for efficient photosynthesis? (Complete the
sentence)
1. Epidermis is thin and transparent . . .
To allow more light to reach the palisade cells
14
Question 10
How is the cellular structure of a leaf adapted
for efficient photosynthesis?
2. Thin cuticle made of wax . . .
To protect the leaf without blocking out light
15
Question 10
How is the cellular structure of a leaf adapted
for efficient photosynthesis?
3. Palisade cell layer at top of leaf . . .
Contains most of the chloroplast, to absorb more
light
16
Question 10
How is the cellular structure of a leaf adapted
for efficient photosynthesis?
4. Air spaces in the spongy layer. . .
Allow carbon dioxide to diffuse between the
stomata and photosynthesising cells, and increase
the surface area
17
Question 10
How is the cellular structure of a leaf adapted
for efficient photosynthesis?
5. Palisade cells contain many chloroplasts. . .
To absorb all the available light
18
Water, Water Everywhere

• Chapter 2

19 Questions
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19
Question 1
How does water move in and out of plant cells?
Through the cell wall and membrane
20
Question 2
What is the role of the plant cell wall?
To provide support
21
Question 3
A lack of water can cause?
Plants to droop (wilt)
22
Question 4

1. Absorption from soil through root hairs
2. Transport through the plant to the leaves
3. Evaporation from the leaves (transpiration)

Describe how water travels through a plant
23
Question 5
Healthy plants must do what?
They must balance water loss with water uptake
24
Question 6
The movement of water across a partially
permeable membrane from an area of high
concentration ( ie. dilute solution) to an area
of high concentration (ie. concentrated solution)
What is osmosis?
25
Question 7
Osmosis is a type of ?
Diffusion
26
Question 8
A membrane that allows some small molecules to
pass through but not larger molecules
Explain the term partially permeable
27
Question 9
What is essential for the support of plants?
The inelastic wall and water
28
Question 10
By increasing the surface area, root hairs
increase the ability of roots to take up water by
osmosis
What is so special about root hairs?
29
Question 11

• Cooling
• Photosynthesis
• Support
• 4. Movement of minerals

Transpiration provides plants with water for?
30
Question 12
How is a leaf adapted to reduce excessive water
loss?

• Waxy cuticle
• 2. Small number of stomata on upper surface

31
Question 13

• An animal cell does not have a cell wall It will
• Swell and burst (lysis) when too much water
  enters
• Shrink, causing crenation, when too much water
  leaves

Describe the effects of water uptake and loss on
animal cells
32
Question 14
How are plants supported by the turgor pressure
within cells?
By the wall pressure acting against inelastic
cell wall
33
Question 15
What is essential for the support of plants?
The inelastic wall and water
34
Question 16
Explain the term flaccid
floppy
35
Question 17
The shrinking of a plant cell due to loss of
water, the cell membrane pulls away from the cell
wall
Explain the term plasmolysis
36
Question 18
Plant cells which are full of water with their
walls bowed out and pushing against neighbouring
cells are turgid
Explain the term turgid
37
Question 19

• Changes in guard cell turgidity to regulate
  stomatal apertures
• 2. Number, distribution, position and size of
  stomata

How is the cellular structure of a leaf adapted
to reduce water loss?
38
Transport In Plants

• Chapter 3

10 Questions
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39
Question 1
What is the role of the
Stem Support, transport Leaf Photosynthesis Fl
ower Reproduction Root Water and mineral
uptake, anchorage
40
Question 2
Describe the arrangement of xylem and phloem in a
dicotyledonous root, stem and leaf
Vascular bundles
41
Question 3
Transpiration, movement of water and minerals
from the roots to the shoot and leaves
What is the function of xylem?
42
Question 4
Translocation, movement of food substances
(sugars) up and down stems to growing and storing
tissues
What is the function of phloem?
43
Question 5
What do xylem and phloem form?
Continuous systems in leaves, stems and roots
44
Question 6
Thick strengthened cellulose wall with a hollow
lumen (dead cells)
Describe the structure of xylem
45
Question 7
Describe the structure of phloem
Columns of living cells
46
Question 8
What is transpiration?
The evaporation and diffusion of water from
inside leaves
47
Question 9

• Increase in light intensity
• 2. Increase in temperature
• 3. Increase in air movement
• 4. Decrease in humidity

Transpiration rate is increased by?
48
Question 10
Why does the rate of transpiration increase when
(Complete the sentence)
1. There is an increase in light intensity?
Because the stomata opens up. This allows more
water to escape
49
Question 10
Why does the rate of transpiration increase when
2. There is an increase in temperature?
Because as the temperature increases, the random
movement of water molecules increases and more
water escapes
50
Question 10
Why does the rate of transpiration increase when
3. There is an increase in air movement?
Because wind causes more molecules near stomata
to be removed. This increases evaporation and
diffusion from inside the leaf
51
Question 10
Why does the rate of transpiration increase when
4. There is an decrease in humidity?
Because in dry conditions there is a very low
concentration of water molecules outside the
leaf. This causes more diffusion of water from
inside the leaf to the outside
52
Plants Need Minerals Too

• Chapter 4

19 Questions
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53
Question 1

• Nitrates
• Phosphates
• Potassium
• 4. Magnesium compounds

Fertilisers contain mineral such as ?
54
Question 2
Poor plant growth may be caused by ?
A lack of one or more minerals in the soil
55
Question 3
Dissolved minerals are absorbed by ?
The roots from the soil
56
Question 4
Why do plants require nitrates?
For protein, which are needed for cell growth
57
Question 5
Why do plants require phosphates?
For respiration and growth
58
Question 6
Why do plants require potassium compounds?
For respiration and photosynthesis
59
Question 7
Why do plants require magnesium compounds?
For photosynthesis
60
Question 8
What would a lack of nitrate cause?
Poor growth and yellow leaves
61
Question 9
What would a lack of phosphate cause?
Poor root growth and discoloured leaves
62
Question 10
What would a lack of potassium cause?
Poor flower and fruit growth, and discoloured
leaves
63
Question 11
What would a lack of magnesium cause?
Yellow leaves
64
Question 12
Where are minerals usually present?
In soil, in quite low concentration
65
Question 13
Why is nitrogen required?
To make amino acids and proteins
66
Question 14
Why is phosphorus required?
To make DNA and cell membranes
67
Question 15
Why is potassium required?
To help enzymes (in photosynthesis and
respiration)
68
Question 16
Why is magnesium required?
To make chlorophyll
69
Question 17
How are minerals taken up into root hair cells?
By active transport
70
Question 18
Active transport can move substances from low
concentration to high concentration
Describe active transport
71
Question 19
Active transport uses energy from ?
Respiration
72
Energy Flow

• Chapter 5

16 Questions
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73
Question 1
What does producer mean?
An organism that makes organic material
74
Question 2
What does consumer mean?
Organisms in an ecosystem that use up organic
matter produced by other organisms
75
Question 3
Where does the energy in a food chain come from?
It comes from plants absorbing sunlight
76
Question 4
What do plants produce when they photosynthesise?
Biomass
77
Question 5
Name three fuels that come from biomass

1. Wood
2. Alcohol
3. Biogas

78
Question 6
A diagram to show the number of living organisms
present at each trophic level in an ecosystem
What is a pyramid of numbers?
79
Question 7
A diagram to show the masses of living organisms
present at each trophic level in an ecosystem
What is a pyramid of biomass?
80
Question 8
How does energy from the sun flow through food
chains?
By photosynthesis and feeding
81
Question 9
Name two less useful forms that energy is
transferred to at each stage in the food chain

• Heat from respiration
• 2. Egestion

82
Question 10
Name two methods of transferring energy from
biomass

• Burning fast growing trees
• 2. Fermenting biomass using bacteria or yeast

83
Question 11
The level at which an organism gets its
food. Primary producers are level one Primary
consumers are level two Secondary consumers are
level three
What does the word trophic mean?
84
Question 12
The shape of a pyramid of biomass shows that the
energy level decreases with increasing trophic
level
Explain how the efficiency of energy transfer
explains the shape of pyramids of biomass
85
Question 13
As each trophic level loses up to 90 of the
available energy, the length of a food chain is
limited to a small number of links
Explain how the efficiency of energy transfer the
limited length of food chains
86
Question 14
Efficiency Energy used for growth Energy
supplied
What is the formula to calculate the efficiency
of energy transfer ?
87
Question 15
Give three reasons for developing biofuels

• Renewable
• 2. Reduces air pollution
• 3. Energy self-reliance

88
Question 16
Discuss choice of use of biofuel

• Eating it
• 2. Feeding it to livestock
• 3. Using it as a fuel
• 4. Growing the seeds

89
Farming

• Chapter 6

22 Questions
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90
Question 1
What do pesticides do?
Kill pests
91
Question 2
What do herbicides do?
Kill plants (weeds)
92
Question 3
Give two examples of pesticides
1. Insecticides (to kill insects) 2. Fungicides
(to kill fungi)
93
Question 4
1. Greenhouses 2. Hydroponics 3. Fish farms 4.
Battery hens
Some farmers use special methods to increase
their production of food such as ?
94
Question 5
1. No artificial fertilisers 2. No herbicides 3.
No pesticides
Describe organic farming methods
95
Question 6
Describe how pests can be controlled biologically
by introducing predators
By introducing a new predator or removing an old
one
96
Question 7
Trying to produce as much food as possible from
the land, plants and animals available
Describe intensive farming
97
Question 8
What is an advantage of intensive farming?
It is efficient
98
Question 9
1. It raises ethical dilemmas 2. Pesticides may
enter and accumulate in food chains 3. Pesticides
may harm organisms which are not pests
What are disadvantages of intensive farming?
99
Question 10
Describe how plants can be grown without soil
(hydroponics)
The plant roots are in specially treated water
that contains the required amounts of fertiliser
and oxygen
100
Question 11
Describe possible uses of hydroponics
1. Glasshouse tomato 2. Plant growth in areas of
barren soil
101
Question 12

• Use of animal manure and compost
• 2. Crop rotation
• 3. Use of nitrogen-fixing crops
• 4. Weeding
• 5. Varying seed planting times

Describe organic farming techniques
102
Question 13
Explain an advantage of biological control
No harmful chemicals used
103
Question 14
Explain a disadvantage of biological control
Takes a long time and often do not kill all the
pests
104
Question 15
Some animal populations may increase because
fewer are eaten while others may decrease because
predators are short of food and have to eat
something else
Explain how removing one organism from a food
chain or web may affect other organisms
105
Question 16
How do intensive food production improve the
efficiency of energy transfer by reducing energy
transfer?

• Reduce energy transfer to competing plants
• 2. Reduce energy transfer to pests
• 3. Reduces heat loss from animals

106
Question 17
Explain how intensive food production improves
the efficiency of energy transfer
1. To competing plants?
Because there are fewer weeds in crops
107
Question 17
Explain how intensive food production improves
the efficiency of energy transfer
2. To pests?
Because there are fewer pests to attack and east
crops or cause disease in livestock
108
Question 17
Explain how intensive food production improves
the efficiency of energy transfer
3. As heat?
Because less heat is lost from animals kept in
sheds and their movement is restricted
109
Question 18
The pesticide in the organisms low down the food
chain gets passed on to predators higher up in
the chain, and they get a lethal dose
How can pesticides accumulate in food chains?
110
Question 19
1. Better control of mineral levels 2. Better
control of disease
Describe two advantages of hydroponics
111
Question 20
1. Lack of support for plants 2. Requires
additional fertilisers
Describe two disadvantages of hydroponics
112
Question 21
1. Expensive chemicals do not have to be
bought 2. No chemical build pollution or build up
in food chains 3. Some people think the products
taste better
Describe three advantages of organic farming
methods
113
Question 22
Describe two disadvantages of organic farming
methods
1. Biological control methods are slow and do not
kill pests 2. Crop yields are reduced and cost of
products are higher
114
Decay

• Chapter 7

9 Questions
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115
Question 1
1. Presence of micro organisms 2. Temperature 3.
Oxygen 4. Moisture
What four things are needed in the process of
decay?
116
Question 2
How can materials be recycled?
Materials can decay and can therefore be recycled
117
Question 3

• Two samples of soil are collected
• 2. One sample is heated but not burned
• 3. Both samples are weighed and then put in
  sealed flasks containing limewater
• 4. After two days the soil samples are re-weighed
• 5. Only the fresh soil sample loses mass
• 6. The limewater in the flask containing the
  fresh soil turns from clear to milky.
• 7. This shows that carbon dioxide is produced

Describe an experiment to show that decay is
caused by decomposers (bacteria and fungi)
118
Question 4
1. Breaking down human waste (sewage) 2. Breaking
down plant waste (compost)
Name two things that micro organisms can be used
for
119
Question 5
1. Canning 2. Cooling 3. Freezing 4. Drying 5.
Adding salt / sugar 6. Adding vinegar
Name six food preservation techniques that reduce
the rate of decay
120
Question 6
What do detritivores feed on and give examples?
They feed on dead and decaying material
(detritus), such as earthworms, maggots,
woodlice, etc
121
Question 7
How do detritivores increase the rate of decay?
They produce larger surface area
122
Question 8
Explain how the following food preservation
method reduces the rate of decay
1. Canning
The food is heated to kill bacteria. The food is
then put into cans and sealed while it is still
hot. This forms a vacuum and prevents the entry
of oxygen and bacteria
123
Question 8
Explain how the following food preservation
method reduces the rate of decay
2. Cooling
The high temperature kills bacteria
124
Question 8
Explain how the following food preservation
method reduces the rate of decay
3. Freezing
Freezing kills and slows down the growth of
others. Freezing food stops bacteria from
reproducing
125
Question 8
Explain how the following food preservation
method reduces the rate of decay
4. Drying
Without water, bacteria and fungi cannot feed and
grow
126
Question 8
Explain how the following food preservation
method reduces the rate of decay
5. Adding salt or sugar
A high concentration of sugar or salt solution
kills some bacteria and fungi and stops the
growth of others. This is an example of osmosis
127
Question 8
Explain how the following food preservation
method reduces the rate of decay
6. Adding vinegar
Vinegar is an acid. Very few bacteria can grow in
acid conditions. Food such as pickled eggs and
chutney are preserved in this way
128
Question 9
Explain the term saprophyte
An organism that breaks down dead organic matter
129
Recycling

• Chapter 8

8 Questions
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130
Question 1
As plants and animals grow, what happens?
They take in chemicals and incorporate elements
from these into their bodies
131
Question 2
What happens when plants and animal die and decay?

• The elements are recycled. These elements
  include
• Carbon
• 2. Nitrogen

132
Question 3

• Plants remove carbon dioxide from air by
  photosynthesis
• 2. Feeding passes carbon compounds along a food
  chain or web
• 3. Plants and animals release carbon dioxide into
  the air, as a product of respiration
• 4. Soil bacteria and fungi, acting as
  decomposers, release carbon dioxide into the air
• 5. Burning of fossil fuels (combustion) releases
  carbon dioxide

Explain how carbon is recycled in nature
133
Question 4

• Plants take in nitrates from the soil to make
  protein for growth
• 2. Feeding passes nitrogen compounds along a food
  chain or web
• 3. Nitrogen compounds in dead plants and animal
  are broken down by decomposers into nitrates and
  returned to the soil

Explain how nitrogen is recycled in nature
134
Question 5
What percentage of the air is nitrogen
78
135
Question 6
Why can nitrogen not be used directly by animals
or plants?
It is too unreactive
136
Question 7
What do soil bacteria and fungi release and how?
Soil bacteria and fungi, acting as decomposers,
release carbon dioxide into the air by respiration
137
Question 8

• Marine organisms make shells made of carbonates
• 2. Shells become limestone
• 3. Carbon returns to air as carbon dioxide during
  volcanic eruption or weathering

Explain how carbon is recycled in the sea
138
End Of B4 Revision
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