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Evolution and the Environment. Biology Adaptations Friday, 12 September 2014. Learning Outcomes. You should be able to: State that organisms need a supply of materials from their surroundings in order to survive and reproduce

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Evolution and the Environment

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Evolution and the Environment

Biology

Adaptations

Friday, 12 September 2014


Learning Outcomes

  • You should be able to:

    • State that organisms need a supply of materials from their surroundings in order to survive and reproduce

    • Describe how organisms are adapted to the conditions in which they live

    • Explain how microorganisms have a wide range of adaptations enabling them to live in a wide range of conditions - extremophiles


How do you know where these animals live from their appearance?

Write one point

for each animal

What physical or behavioral

adaptations might they have


carnivore

What makes an animal an animal and a plant a plant – what’s the difference?

Where do they get the

things they need?

herbivore

http://www.youtube.com/watch?v=BQ1JaYxBH40


Flanimals

  • Create a creature.

    • Include a fact file on

      • Where it lives

      • What is eats

      • How it mates

      • How it finds its food

      • How it breathes

      • How it sees


How are these adapted to their environment?

  • Use the books to help annotate these animals adaptations. You have one minute to write as many adaptations down as possible

    • Polar bear

    • Arctic fox

    • Camel

    • Cactus


What are the benefits of animal being adaptable?


Needs

Reason why

Needs

Reason why

Animal and plant needs


What are these?


Microbes...

  • There are millions of different types

  • They live everywhere imaginable on earth!

  • They are Pathogens as well as useful microorganisms

  • A Pathogen is something that disrupts the bodies normal systems in a negative way


Living on the edge

http://www.teachersdomain.org/resource/ess05.sci.ess.eiu.lifecondtn/

Some organisms live in extreme environments, e.g. where there are high levels of salt, high or low temperatures or high pressures. These organisms are known as extremophiles.


Deep under the ocean there are hydrothermal vents where heated seawater escapes from cracks in the earth’s crust.

This environment has high temperatures, high pressure and no sunlight, yet life manages to adapt to these conditions.

375°C

bacteria which live here can turn hydrogen sulfide in the water into nutrients, they live in giant tubeworms.


  • Any idea what these words mean?

  • Thermophiles,

  • Hyperthermophiles,

  • Psychrophiles,

  • Halophiles,

  • Acidophiles,

  • Alkaliphiles,

  • Barophiles,

  • Endoliths.


Any idea what these words mean?

Thermophiles – like heat

Hyperthermophiles - like extreme heat

Psychrophiles – like cold

Halophiles – like salty conditions

Acidophiles – like acidic conditions

Alkaliphiles – like alkaline conditions

Barophiles – like high pressure conditions


Any idea what these words mean?

Thermophiles – like heat

Hyperthermophiles - like extreme heat

Psychrophiles – like cold

Halophiles – like salty conditions

Acidophiles – like acidic conditions

Alkaliphiles – like alkaline conditions

Barophiles – like high pressure conditions


Mini test

  • What is an extremophile?

  • What are some of the environmental challenges facing these organisms?

  • Explain how some organisms meet these challenges.

  • After learning about the conditions under which extremophiles live, do you think it is reasonable to argue that life could probably exist on other planets? Explain

.


Learning Outcomes

  • You should be able to:

    • State that organisms need a supply of materials from their surroundings in order to survive and reproduce

    • Describe how organisms are adapted to the conditions in which they live

    • Explain how microorganisms have a wide range of adaptations enabling them to live in a wide range of conditions - extremophiles


Adaptation in animals


Learning Outcomes

  • All student should be able to:

    • Define the term ‘adaptation’.

  • Most students should be able to:

    • Describe how animals are adapted to survive in cold climates.

    • Describe how animals are adapted to life in a dry climate.

  • Some students should also be able to:

    • Suggest how organisms are adapted to the conditions in which they live, when provided with appropriate information.


Plasticine

  • Make the smallest shape possible

  • Then the biggest?


Surface area Vs volume ratio

  • Take a 1cm cube:

  • Volume        = 1 x 1 x 1 = 1cm3Surface area = 6 faces x (1 x 1) = 6cm2

  • So for 1cm3 of volume there are 6cm2 of surface area to lose heat from, 6 / 1 = 6cm2 per 1cm3.

  • surface-area : volume ratio is 6:1

  • Now take a 3cm cube, identical shape:

  • Volume         = 3 x 3 x 3 = 27cm3Surface area  = 6 faces x (3 x 3) = 54cm2

  • So for 27cm3 of volume there are 54cm2 of surface area to lose heat from, 54 / 27 = 2cm2 per 1cm3.

  • surface-area : volume ratio is 2:1

This means that for identically shaped animals of

different sizes, the large one will keep its temperature

more easily. Being big means being warmer.


Where animal live

  • Look at the volume ration to surface area, and where the animal might live – is there a pattern?


Effect of insulation on heat loss

  • Animals coats will effect how much heat they lose. You are going to investigate HOW big that effect will be.

  • Method

    • Fill three conical flasks of the same volume of hot water.

    • One flask is left uncovered, second one should be surrounded by an insulating layer of cotton wool, and the third one with bubble wrap.

    • Choose a variable to measure

You need to plan it first


Include

  • Aim

  • Hypothesis

  • prediction,

  • variables

  • Results table

  • Graph

  • Analysis

  • Conclusion


Plenary

  • Using the key words below, write a brief paragraph on how coats have an effect on how much heat an animal will lose.

  • Key words

    Adaptation, surface area, volume, coat thickness, air pockets, insulation


Learning Outcomes

  • All student should be able to:

    • Define the term ‘adaptation’.

  • Most students should be able to:

    • Describe how animals are adapted to survive in cold climates.

    • Describe how animals are adapted to life in a dry climate.

  • Some students should also be able to:

    • Suggest how organisms are adapted to the conditions in which they live, when provided with appropriate information.


Adaptations in Plants

  • Learning Outcomes

    • All students should be able to

    • give an adaptation of a cactus

    • Most students should be able to:

    • Describe the adaptations shown by plants that live in dry environments.

    • Some students should also be able to:

    • Explain how these adaptations reduce the quantity of water lost by the plant.

    • Explain the importance of water-storage tissues in desert plants.


5 minutes to discuss these questions

  • Why is water so important to a plant

  • How does it get this water

  • What does it do with it?

  • What is transpiration


Transpiration

Plants take in water through their roots in the soil…


…it moves up through the plant…

Transpiration


…..and is lost through the leaves in the transpiration stream.

Transpiration

Corel 178(NT)


Transpiration


There are small openings called stomata in the leaves of a plant.

Stomata


These open to allow gases in and out for photosynthesis and respiration. But at the same time water is lost by evaporation.

Stomata


When it is hot and dry, photosynthesis andrespiration take place quickly. As a result,plants also very quickly lose water.

Rate of transpiration


The potometer

A potometer can be used to measure the rate of transpiration.


What is a succulent?


Succulents

·These are water-retaining plants.

·They are adapted to arid (dry) climates or soil conditions, such as deserts.

·Succulent plants store water in their leaves, stems and/or roots.

·The storage of water often gives succulent plants a more swollen or fleshy appearance than other plants

·

·Can you think of any?

Aloe Vera

They have other water-saving features


Draw a cacti and

Label these things

On the diagram….


1) Fewer stomata:


2) A compact, cushion-like growth:

3) Stems, rather than leaves,

as the main site of photosynthesis.


How can succulents go days without water

4) Hairy or spiny outer surface

to reduce water loss:


5) Ribs to allow rapid increases in plant volume:


Distribution of succulents

  • What does this map show?


Cactus

  • King of the succulents.

  • Can you remember some of their adaptations?


How is a cactus adapted?

How is a cactus adapted to life in a very hot, dry climate?

  • water is stored in a fleshy stem, and a thick, waxy cuticle reduces water loss

  • leaves are narrow spines to reduce water loss and protect from predators

  • roots are either very deep, or shallow and widespread to catch surface water

  • rounded shape means that the surface area to volume ratio is low, and this reduces water loss.


Observing Stomata

Paint your leaf with nail varnish

Allow to dry

Gently peel off

Observe and draw under the microscope

What do you notice about the

different leaves and their stomata?


Plant adaptations

Plants lose water from the surface of their leaves. Pines and cacti are specially adapted to minimize water loss.

A rubber plant lives in hot, wet conditions. Its leaves are smooth and waxy to allow water to run off quickly. This unblocks the stomata and allows gas exchange.

It also produces a sticky sap, which glues together the mouth parts of insects who try to eat it!


Curled leaves.

Adaptations for plants growing in a dry environment

  • Stomata on the

  • curled side only.

  • Moist air trapped

  • inside the curl.

  • Thick waxy cuticle.


Marram grass leaves will even uncurl slightly in the wet and curl up more in the dry.

Adaptations for plants growing in a dry environment

Corel 46(NT)


What do flowers do?

Flowers enable plants to reproduce sexually. For this to happen, pollen from one flower must be carried to another flower – either on the same plant or on a different plant.

This is called pollination.

In what ways can pollination take place?

  • Pollen is carried by insects from one flower to another.

  • Pollen is blown by wind from one flower to another.


Adaptations for insect pollination

How are flowers adapted for pollination by insects such as bees and butterflies?

nectar, a source of food for insects, is deep within the flower

large, sticky pollen grains become attached to the insect’s body

stiff anthers and stigmas are positioned where insects must brush past them

colourful, scented petals attract insects


Adaptations for wind pollination

How are flowers adapted for pollination by the wind?

huge numbers of light, tiny pollen grains

small, dull-coloured petals

anthers hang loosely outside flower so wind can blow pollen

long, feathery stigma hanging outside flower so pollen can be trapped


Unusual plant adaptations

Plants can livein acid or waterlogged soils where there is little nitrate. Some plants have evolved a rather cunning adaptation to obtain the nutrients they need.

Pitcher plants have a large hollow filled with fluid that traps insects or other small organisms that may fall in.

Hairs on the slippery inside of the plant are angled down to ensure that the victim cannot escape!

The plant digests its victims to absorb the nitrates it needs!


Plenary


The potometer

A potometer can be used to measure the rate of transpiration.


Graph of bubble movement against time.

Transpiration rate


The steeper the graph, the faster the transpiration rate!

Transpiration rate


Which potometer experiment was run in drier air?

Transpiration rate


The drier the air, the faster the transpiration rate!

Transpiration rate


Plenary

  • A amateur cactus enthusiast Daiv Freeman, has written to ‘Cacti Weekly’ to ask what the best conditions are for him to grow his Cacti.

The editor has asked you to write him a response explaining why these conditions are bets and how the cacti are suited to them.


Adaptations in Plants

  • Learning Outcomes

    • All students should be able to

    • give an adaptation of a cactus

    • Most students should be able to:

    • Describe the adaptations shown by plants that live in dry environments.

    • Some students should also be able to:

    • Explain how these adaptations reduce the quantity of water lost by the plant.

    • Explain the importance of water-storage tissues in desert plants.


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