Dessert animals have
adapted to save water
and keep cool
Animals that live in hot, dry
conditions need to keep cool and
use water efficiently
Large surface area compared to volume
This lets desert animals lose
more body heat which helps to
stop them overheating
Efficient with water
Desert animals lose less water by
producing small amounts of
concentrated urine
They also make very little sweat.
Camels are able to do this by
tolerating big changes in body
temperature while kangaroo rats live
in burrows underground where its
cool
Good in hot conditions
Desert animals have very thin
layers of body fat and a thin coat
to help them lose body heat e.g.
camels keep nearly all their fat in
their humps
Camoflage
A sandy colour gives good
camouflage to help them avoid
predators or sneak up on prey
Arctic animals have adapted to reduce heat loss
Animals that live in really
cold conditions need to
keep warm
Small surface area compared to volume
Animals living in cold conditions have
a compact shape to keep their surface
area to a minimum this reduces heat
loss
Well insulated
They also have a thick layer of blubber
for insulation this also acts as an energy
store when food is scarse
Thick, hairy coats keep body
heat in and greasy fur sheds
water (this prevents cooling due
to evaporation)
Camouflage
Arctic animals have
white fur to help
them avoid
predators or sneak
up on prey
Plants are adapted to their environment
Desert plants have adapted to having little water
Desert dwelling
plants make best use
of what little water is
available
Small surface area compared to volume
Plants lose water vapour from
the surface of their leaves.
Cacti have spines instead of
leaves to reduce water loss
They also have a small surface area
compared to their size (about 1000 times
smaller surface area than normal plants)
which also reduces water loss
Water storage tissue
a cactus stores water in its thick stem
Maximising water absorbtion
Some cacti have shallow
but extensive roots to
absorb water quickly over a
large area. Others have
deep roots to access
underground water
Some plants and animals are adapted to deter predators
There are various special features
used by plants and animals to help
protect them from getting eaten
Some plants and animals have armour - like roses
Others produce poisons - bees and poison ivy
And some have amazing warning colours to scare off predators - like wasps
Microorganisms have a huge variety of adaptions
Some microorganisms are known
as extremophiles - they are
adapted to live in seriously
extreme conditions like super hot
volcanic vents, in very salty lakes
or at high pressure on the sea bed
Competition and Environmental change
Organisms compete for resources to survive
Organisms need things from their
environment and from other organisms to
survive and reproduce
Plants need light, space, water and minerals from the soil
Animals need space, food, water and mates
Organisms compete with
other species for the same
resources
Environmental changes are caused by different factors
The environment in which plants and animals
live changes all the time. These changes are
caused by living and non-living factors such
as:
Living
A change in the
occurrence of infectious
diseases
A change in the number of predators
A change in the
number of prey or the
availability of food
sources
A change in the number of types of competitors
Non-living factors
A change in average temperature
A change in average rainfall
A change in the level of air of water pollution
Environmental changes affect populations in different ways
Population size increases
Population size decreases
e.g. the number of bees in the US is falling rapidly
Population distribution changes
A change in distribution means a change in where on organism live
Measuring Environmental Change
You can measure
environmental change
using living indicators
Some organisms are very sensitive to
changes in their environment and so can be
studied to see the effect of human activities
these organisms are known as indicator
species
For example air pollution can be
monitored by looking at particular types
of lichen that are very sensitive to the
concentration of sulfur dioxide in the
atmosphere. The number and type of
lichen at a particular location will
indicate how clean the air is
If raw sewage is released into a river the
bacterial population in the water increases and
uses up oxygen. Some invertebrate animals
like mayfly larvae are good indicators for water
pollution because they are very sensitive to the
concentration of dissolved oxygen in the water.
If you find mayfly larvae in a river it indicates
that the water is clean
Other invertebrate species have adapted
to live in polluted conditions so if you see a
lot of them you know theres a problem
Non living indicators
They use satellites to
measure the
temperature of the sea
surface and the amount
of snow and ice cover.