Practise Adaptations. 14 exam-style questions plus unlimited generated ones on this subtopic, at up to four difficulty levels, with full mark schemes and a progress tracker. Free, no account needed.
Adaptations are features that help an organism survive in the conditions where it normally lives. Expect to classify adaptations as structural, behavioural or functional, and to explain the features of plants, animals and microorganisms (including extremophiles) from information you are given.
Grade by grade
What you need to be able to do, from the first marks up to the top grade.
3
Define an adaptationA feature that helps an organism survive in the conditions where it normally lives.
4
Classify adaptations as structural, behavioural or functionalStructural means body features, behavioural means what it does, and functional means processes inside the body.
5
Define an extremophile and give an exampleAn organism that lives in extreme conditions of temperature, pressure or salt concentration, e.g. bacteria in deep sea vents.
6
Explain adaptations to hot, cold and dry environmentsLink each feature to heat loss or water loss, e.g. spines instead of leaves reduce water loss.
7
Explain adaptations using surface area to volume ratioA large, compact body has a small surface area to volume ratio, so it loses heat more slowly.
8
Explain unfamiliar adaptations from given informationUse the description or data to link each feature to a specific survival problem in that habitat.
Notes
Three types of adaptation
An adaptation is a feature that enables an organism to survive in the conditions where it normally lives.
Structural: features of the body, e.g. thick fur, sharp claws, a thick waxy cuticle on leaves, camouflage colouring.
Behavioural: the way an organism acts, e.g. migrating to warmer places in winter, being active at night to avoid the daytime heat, huddling together to keep warm.
Functional: processes inside the body, such as metabolism and reproduction, e.g. a desert animal producing very little sweat and very concentrated urine to save water, or a mammal lowering its metabolic rate while it hibernates.
Hot, cold and dry places
Cold: thick fur or a layer of fat insulates the body. A large body with small ears has a small surface area to volume ratio, so less heat is lost.
Hot: large ears and thin fur increase heat loss. A large surface area to volume ratio helps an animal lose heat.
Dry (plants): spines instead of broad leaves and a thick waxy cuticle reduce water loss; long or widespread roots absorb as much water as possible; swollen stems store water.
Camouflage, such as white fur in snow or sandy colours in a desert, helps animals hide from predators or approach prey unseen.
Extremophiles
Some organisms live in very extreme conditions, such as high temperature, high pressure or high salt concentration. They are called extremophiles.
Example: bacteria living around deep sea vents survive very high temperatures and pressures.
Their enzymes and other proteins keep working in conditions that would denature the enzymes of most organisms.
Answering adaptation questions
Name the feature, then say how it helps in that environment, e.g. 'thick fur traps air, which insulates the body, so less heat is lost'.
Cheatsheet
Adaptation = a feature that helps an organism survive in its normal conditions
Structural = body features (e.g. thick fur, spines)
Behavioural = actions (e.g. migration, huddling)
Functional = processes inside the body, such as metabolism and reproduction (e.g. concentrated urine)
Small surface area to volume ratio → less heat lost (cold places)
Large surface area to volume ratio → more heat lost (hot places)
Extremophile = lives in extreme conditions of temperature, pressure or salt concentration
Example extremophile: bacteria in deep sea vents
How to answer each type of question
Classify an adaptation
1 mark each4
A body feature you could see or measure is structural.
Something the organism does is behavioural.
A process inside the body is functional.
Example. Classify each adaptation of a camel as structural, behavioural or functional. (a) Long eyelashes that keep sand out of its eyes. (b) Producing very concentrated urine. (c) Resting in the shade during the hottest part of the day.
Identify the problem in the habitat (cold, heat, lack of water, predators).
Name the feature.
Explain how the feature solves the problem, using 'so' or 'which'.
Example. Arctic foxes live in very cold places. They have thick fur, which is white in winter, and small ears. Explain how two of these features help the Arctic fox to survive. (4 marks)
Show the model answer
Any two features explained, for example: Thick fur traps air / insulates the body (1), so less heat is lost (1). White fur camouflages the fox against snow (1), so it can approach prey without being seen (1). Small ears have a small surface area (1), so less heat is lost from them (1).
Suggest how a plant is adapted to a dry habitat
3 marks6
Think about getting water (roots), storing water (stems) and losing less water (leaves, cuticle, stomata).
Match each feature in the information to one of these.
Explain each feature; do not just list them.
Example. Marram grass grows on sand dunes, where the sand holds little water. In dry weather its leaves roll up, with the stomata on the inside of the roll. Its roots can grow more than a metre deep. Suggest how these features help marram grass to survive.
Show the model answer
Rolled leaves trap moist air around the stomata / expose less surface to the air (1), so less water is lost by evaporation from the leaves (1). Deep roots can reach water far down in the sand (1).
Explain how extremophiles survive
2 marks7
Name the extreme condition (temperature, pressure or salt concentration).
Explain that their enzymes and proteins are not denatured in that condition, so their reactions can continue.
Example. Some bacteria live in hot springs at 80 °C. Suggest why most organisms cannot survive at this temperature, but these bacteria can.
Show the model answer
In most organisms, enzymes are denatured at 80 °C / their active sites change shape (1). These bacteria have enzymes that keep their shape at high temperatures, so reactions such as respiration can continue (1).
Shortcuts and memory tricks
S-B-F: Structural = what it looks like, Behavioural = what it does, Functional = what goes on inside.
Big and round keeps heat around: large, compact bodies have a small surface area to volume ratio.
For every feature, ask 'so what?': feature → effect → how that helps survival.
Where marks are lost
Listing features without explaining how each one helps the organism survive.
Saying the organism 'adapted itself' or 'chose' to change. Adaptations come about by natural selection over many generations.
Mixing up surface area with surface area to volume ratio: in the cold, a small ratio reduces heat loss.
Calling migration or huddling a structural adaptation. They are behavioural.
Writing that extremophiles 'live in extreme places' without naming the condition (temperature, pressure or salt).
Exam technique
Explain questions usually give 1 mark for the feature and 1 mark for how it helps. Always pair them up.
Unfamiliar organisms are common. The clues you need are usually in the question.
Use scientific words: insulation, camouflage, surface area to volume ratio, water loss, denatured.
Sample questions
Written for this site in the style of AQA exam questions. They are not taken from real past papers.
Question 1Easy4 marks
Organisms have adaptations that enable them to survive in the conditions in which they normally live.
(a) Which is a behavioural adaptation? Tick (✓) one box.[1]
A hedgehog hibernates during the winter.
A polar bear has a thick layer of fat.
A cactus stores water in its stem.
A desert rat produces very concentrated urine.
(b) Which is a functional adaptation? Tick (✓) one box.[1]
A camel has long eyelashes.
An Antarctic fish makes antifreeze proteins in its blood.
Penguins huddle together in cold weather.
A cactus has spines instead of leaves.
(c) Bacteria that live near deep-sea vents are extremophiles. Give two extreme conditions that these bacteria are adapted to.[2]
Show the answer and mark scheme
(a)Answer: A hedgehog hibernates during the winter.
(b)Answer: An Antarctic fish makes antifreeze proteins in its blood.
(c)
high temperature
high pressure
no light
high concentrations of dissolved chemicals / minerals
Question 2Medium7 marks
Cacti are plants that live in hot deserts where there is very little rain.
(a) Cacti have spines instead of broad, flat leaves. Explain how this helps a cactus to survive in the desert.[2]
(b) The stem of a cactus is thick and swollen. Suggest why.[1]
(c) The stem is covered by a thick layer of wax. Explain how this helps the cactus to survive.[1]
(d) Some cacti have long roots that grow deep into the ground. Others have shallow roots that spread over a wide area. Suggest how each type of root helps a cactus to obtain water.[2]
(e) The stem of a cactus is green. Suggest why this is important for the cactus.[1]
Show the answer and mark scheme
(a)
smaller surface area (for evaporation) / fewer stomata
(so) less water is lost by transpiration / evaporation
(b)
it stores water
(c)
it reduces water loss by evaporation / it is waterproof
(d)
deep roots reach water far below the surface
shallow, widespread roots absorb rainwater quickly over a large area (before it evaporates)
(e)
the stem photosynthesises / contains chlorophyll, because the spines cannot photosynthesise (so the stem must make glucose)
Question 3Hard8 marks
A small rodent lives in a hot, dry desert. During the day the air temperature can reach 45 °C, and at night it can fall to 10 °C. There is very little rain and there are few plants. Owls and snakes hunt the rodents. Some features of the rodent are listed:
it stays in a deep burrow during the day and comes out to feed at night
its kidneys produce a very small volume of very concentrated urine
its faeces are very dry
it obtains almost all its water from the seeds it eats and from respiration
it has large ears with many blood vessels close to the surface
it has sandy-coloured fur.
(a) Explain how the features of the rodent adapt it to survive in the desert.[6]
(b) Suggest why having large ears could be a disadvantage to the rodent when it comes out at night.[2]
Show the answer and mark scheme
(a)
staying in a burrow during the day avoids the highest temperatures; the burrow is cooler and more humid, so less water is lost by evaporation (behavioural)
feeding at night when it is cooler reduces water loss and the risk of overheating
very concentrated urine / a small volume of urine conserves water (functional)
dry faeces mean less water is lost in egestion
getting water from seeds and respiration means it does not need to drink, as there is little water available
large ears give a large surface area; blood close to the surface transfers heat to the surroundings, cooling the rodent (structural)
sandy fur camouflages it against the sand, so it is less likely to be seen by owls or snakes
Marked with levels of response: the full level descriptors are in the app.
(b)
large surface area so more heat is lost when the air is cold (10 °C)
(so) it must respire more / use more food to keep its body temperature constant