Transcript B1b 5 Adaptation for Survival

B1b 5 Adaptation for
Survival
5.1 Adaptation in animals
Lesson objectives
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Understand how animals adapt to their
environment
Understand the relationship between body size
and surface area
Variety of conditions
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The Earth has a massive variety of conditions
Arctic wasteland
 Desert
 Tropical Rainforest
 Moorland
 Deep ocean
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Extreme conditions – all have life
Adapted to the conditions
Extreme cold
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Arctic animal are adapted to deal with it
Biggest problem – keeping warm
The amount you lose depends on how much
skin you have
Surface area/volume ratio (SA/V)
Lower the ratio – less you lose
Polar Bear
Polar Bear
Small ears help to reduce heat
loss.
Thick fur and a thick layer of
body fat insulate from the cold.
White fur acts as
camouflage??????
Large feet spread the body’s
weight. The wide paws act as good
paddles
and snow shoes.
Polar Bear
Eyes have brown irises
to reduce the glare from sunlight
reflection.
Greasy fur repels water and
keeps the bear dry.
Skin is actually black
to absorb any heat transmitted
through
the hairs.
Body surface area is
small compared to volume
to reduce heat loss.
Hot climate
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Very difficult
Very dry
Scorching during day
Freezing during night
Body temperature
must be stable
Best way is sweating
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Lose water
Need other
adaptations
How is a camel adapted?
Brown coat for camouflage.
Fat is stored in the hump. There is
no other body fat to prevent
overheating.
Loses little water through
sweating or urine.
Long, thin legs mean the body
surface area is large compared to
volume
to increase heat loss.
Wide feet for spreading
body weight over soft
shifting sand.
Adapting to a desert environment
Nostrils can close when
needed to protect the
camel in sandstorms.
A very varied diet, ranging
from grass and bark to
thorns and bones, is eaten.
Ears are lined with
fur to prevent sand and dus
from
getting in.
Long eyelashes
protect the eyes from
sand and dust.
How are leaves adapted?
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Broad and flat
Veins carry water to the leaf and
take food from the leaf
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help to support the leaf.
Plant cells contain chloroplasts
with chlorophyll.
Small holes called stomata in the
underside of a leaf allow gases
in and out
Water evaporates from leaves
Prickly customers
Thick, waxy surface to
reduce water loss succulents
Leaves are narrow spines
that reduce water loss and protect
from predators.
Stores water in fleshy stem.
Plant surface area is
small compared to volume to
reduce water loss.
Some have shallow,
spreading roots for surface
water, others
have deep roots.
Learning outcomes
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How are animals adapted to their environment?
Why is SA/V ratio important?
What adaptations do plants have?