GCSE AQA: Biology 1.4

Core Science: biology 1.4

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B1.4 Adaptations
To survive and reproduce, organisms need a supply of materials from their surroundings and other living organisms
Plants often compete with each other for light and space, and for water and nutrients from the soil
Animals often compete with each other for food, water, mates and territory. In the wild territorial disputes
between species or members of a species are common; the best adapted animals will survive.
In most UK woodlands, the North American grey squirrel has displaced the native red squirrel mostly because it
gets more food; the grey squirrel can feed more at ground level and digest acorns which red squirrels can't.
Organisms, including microorganisms have features (adaptations) that enable them to survive in the conditions in
which they normally live.
So-called extremophiles may be tolerant to high levels of salt, high temperatures or high pressures
There are creatures that happily live on the deep ocean beds where the pressure from the water above is
Animals and plants may be adapted for survival in the conditions where they normally live, e.g. deserts, the
Animals may be adapted for survival in dry and arctic environments by means of:
Changes to surface area - heat/water transfer factor
Desert animals tend to have a large surface area/volume ratio to allow excess body heat to be readily lost; this
helps overheating, particularly as they do not sweat much and produce smaller volumes of concentrated urine,
both helping to reduce water loss.
Animals living in very cold climates tend to have a smaller surface area to minimise heat loss; their bodies need
to compact with a minimum volume - 'roundish' to minimise the surface area through which heat is lost. The
arctic fox and wolves have short a snout and ears to minimise surface area, hence minimise heat loss.
Thickness of insulating coat
Desert animals have thinner coats than animals in colder a climate, which aids heat loss.
Animals living in very cold climates have a long winter coat with thick dense under fur to minimise heat loss-
it's an extremely good insulator, but the fur must be in good condition to trap insulating air and keep cold
water away from the skin. Animals like the arctic fox and bears have this fur, meaning they can survive at
freezing temperatures.
Amount of body fat
Desert animals have thin layers of body fat compared to animals in colder climates, which aids heat loss.
Animals in arctic regions have thick layers of insulating fat or blubber and these also act as an important energy
store - fat has a very high calorific value, useful in lean times and scarcity of food
Desert animals have sand coloured coats which give good camouflage to minimise being seen and attacked by
predators and enables them to camouflage themselves to hunt prey
Arctic animals like polar bears have white fair to blend in with the snowy background to increase the chances of
a kill. Smaller white coated animals are less likely to seen and caught. Birds like the ptarmigan stand a better
chance of survival from predators turning white in colour in winter, and brown in the summer, thereby blending
into the landscape with the change in seasons
Plants may be adapted to survive in dry environments by means of:
Changes to surface area, particularly of the leaves - through which water is naturally lost by transpiration
To reduce the surface area, to reduce water loss, plants like cacti have thin spines instead of broader leaves.
Water-storage tissues
Plants like cacti have relatively thick fleshy stems which contain groups of specialised cells that store water
Extensive root systems
Cacti generally have one of two kinds of root system. Some have relatively few roots, but roots that can
burrow deep into the ground to seek out underground water. Other cacti have many shallow spread out roots
that can rapidly absorb water e.g. if it rains, which may be very infrequent in desert regions.

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Animals and plants may be adapted to cope with specific features of their environment; these specialised
features include thorns, poisons and warning colours to deter predators' e.g.…read more


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