· Web viewPlants such as hydrilla, ... Teaching Tip: Read the new words out loud and have pupils repeat each word after you so they can learn to pronounce the words correctly

© 2012 Alston Publishing House Pte Ltd Science SMART Teacher’s Guide Grade 6 Chapter 4 Lesson Plans

Lesson PlansChapter 4: AdaptationsTotal number of periods: 28 periods

Overview of Lesson Plans

What Are Adaptations? (3 periods)Lesson Specific Instructional Objectives Cambridge Primary Scientific Enquiry

SkillsProcess Skills 21st Century Skills Number of

Periods4.1 Pupils should:

- know that adaptations are special characteristics that organisms have to survive in their natural habitat

- know that there are two types of adaptations: structural and behavioural adaptations

- know that structural adaptations refer to the physical features of an organism

- know that behavioural adaptations refer to the way an organism acts or behaves to stay alive

Make a variety of relevant observations and measurements using simple apparatus correctly. (Eo1)

Identify simple trends and patterns in results and suggest explanations for some of these. (Eo5)

Explain what the evidence shows and whether it supports predictions. (Eo6)

Link evidence to scientific knowledge and understanding in some contexts. (Eo7)

ObservingInferringClassifying Communicating

Think creativelyReason effectivelyCommunicate clearlyInteract effectively with others

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How Are Animals Adapted to Their Environment? (12 periods)Lesson Specific Instructional Objectives Cambridge Primary Scientific Enquiry



- know how different animals adapt to the conditions in their natural habitats

- know that animals have adaptations for various purposes: moving in water, breathing in water, flight, coping with extreme cold, coping with extreme heat, obtaining food, protection from predators and reproduction


Collect evidence in a variety of contexts. (Ep1)

ObservingInferringClassifyingCommunicatingHypothesisingContrastingAnalysing

Communicate clearlyInteract effectively with othersThink creativelyReason effectivelyUse systems thinkingSolve problems

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Test an idea or prediction based on scientific knowledge and understanding. (Ep2)

Suggest questions that can be tested and make predictions; communicate these. (Ep3)

Design a fair test and plan how to collect sufficient evidence. (Ep4)

Manage projectsApply technology effectivelyWork independentlyBe self-directed learnersCollaborate with others

How Are Plants Adapted to Their Environment? (10 periods)Lesson Specific Instructional Objectives Cambridge Primary Scientific Enquiry



- know how different plants adapt to their environment- know that plants have adaptations for various purposes:

obtaining sunlight, obtaining water, dispersing seeds and pollination




ObservingInferringAnalysingCommunicating

Think creativelyReason effectivelyBe self-directed learnersApply technology effectively Work independently Interact effectively with othersCollaborate with othersCommunicate clearly

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How Are Different Organisms Suited to Their Habitats? (3 periods)Lesson Specific Instructional Objectives Cambridge Primary Scientific Enquiry



- know how organisms are adapted to their habitats - know the adaptations that various organisms in the pond

habitat have - know the adaptations that various organisms in the

garden habitat have





ObservingInferringAnalysingCommunicatingPredicting

Think creativelyReason effectively

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Main Lesson Plans

Lesson 4.1BSCS 5E Lesson Notes Resources

Engage:Pupils are taught about the importance of adaptations to the survival of organisms

Engage:Pupils are given questions to

Background: Pupils learnt in Grade 4 Chapter 2: Introducing Habitats about the different types of habitats and the organisms that can be found in them. Both animals and plants are adapted to the conditions of the habitats in which they live. Adaptations refer to special characteristics that organisms have to help them survive in their natural habitats. It is a feature that is common in a population because it provides some improved functions. Each adaptation has been produced by evolution as the adaptation has developed over many generations. Organisms that are not adapted to their environment will either move away from their habitat or die out. Thus, adaptations are a result of natural selection.

Teaching Tip: Draw the following mind map.

Chapter openerUse the scene in the opener to ask pupils: Do you think Ari can keep a penguin as a pet? Why? (Answer: No, because he will need to simulate the same cold

environment like in the enclosure for the penguin to survive.)

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Cope with physical conditions such as temperature and light

Protect themselves from predators

allow organisms to

allow organisms to

allow organisms to

allow organisms to

Get air, food and water

Adaptations

Reproduce


stimulate thinking and generate interest in the topic

Elaborate: Pupils reinforce their knowledge about the difference between structural and behavioural adaptation

What is the natural habitat of penguins like? (Answer: It is cold and surrounded by water.) How are the penguins able to survive there? (Answer: They have a coat of feathers and a layer of fat under their skin to

keep them warm.) How do penguins reproduce under such harsh conditions? (Answer: Penguins lay eggs and hatch their young before the

coldest part of winter sets in.) How are penguins able to swim fast enough to catch fish in the water? (Answer: Penguins have streamlined bodies to help

them swim fast.)

Explain that: Penguins have special physical features to help them survive in their environment.

What’s In This Chapter?, What Will I Learn?Emphasise to pupils what their learning journey will be like for this chapter. Adaptations can be structural or behavioural. Both animals and plants can have adaptations.

Teaching Tip: Trace the path of the mind map by reading out loud.

What Are Adaptations?Background: An adaptation is a structural or behavioural characteristic that has developed to allow an organism to survive better in its habitat. A structural adaptation refers to a special physical characteristic of an organism that helps it to survive in its habitat. An example of a structural adaptation is the stripes found on a zebra. These stripes help a zebra camouflage itself so that it is not easily noticed by its predators. A behavioural adaptation refers to the special way an organism acts under certain circumstances that helps it to survive. For example, a squid will eject jet-black ink to protect itself when confronted by an enemy.

Teaching Tip: Draw the following table on the board to help pupils remember the difference between structural adaptation and behavioural adaptation.

Structural adaptation Behavioural adaptationThe special physical feature an organism has that helps it to survive in its habitat

The special way an organism behaves that helps it to survive in its habitat

For example, a duck has webbed feet to help it paddle in the water, while a cactus plant has needle-like leaves to reduce their surface area so that there is less evaporation,

For example, a grizzly bear hibernates during wintertime when food is scarce, while a mimosa plant closes its leaves when something comes into contact with them so as to

Textbook page 62

Textbook pages 63—64

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Explore:Pupils learn more about new concepts by going through different scenarios

thus preventing the loss of water from the plant dislodge insects

Activity: Divide pupils into groups of four or five and have them look at pictures of ways people live, work and play all over the world. Make a list of some ways humans are different from other animals in their abilities to adapt. From the pictures, get each group to choose the most interesting adaptation they come across and share it with the rest of the class.

Teaching Strategy: Relating to real life

Process Skills: Observing, Inferring, Classifying, Communicating

21st Century Skills: Think creatively; Reason effectively; Communicate clearly; Interact effectively with others

Project Idea: Divide pupils into groups of four or five and have them look at how the structural adaptation for a particular purpose differs between a fish, an amphibian and a reptile. Pupils are required to make models to demonstrate the structural adaptation in each animal. The structural adaptation that they choose must be different in at least two of the three animals that they model. For example, they might choose to show the structural adaptations these animals have for moving, eating or surviving in a hot climate.


21st Century Skills: Think creatively; Reason effectively; Communicate clearly; Interact effectively with others

Workbook pages 51—53Activity 1: Amazing Beaks

Consolidation Worksheet 1

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Explain: Pupils learn important concepts and key words

Evaluate: Pupils compare the adaptations between modern day animals and prehistoric marine animals

How Are Animals Adapted to Their Environment?Adaptation for moving in waterTeaching Tip: Draw the following table to summarise the characteristics of adaptations for moving in water. Take note of the key words highlighted in bold.

Adaptations for moving in water Most aquatic animals have a streamlined body shape that reduces water resistance to enable the animal

to move faster in water, e.g. dolphin. Some aquatic animals have a layer of blubber or fat which helps them to stay buoyant in water. Many aquatic animals have modified limbs to help them propel their bodies forward and control their

movement in water, e.g. fish have fins, seals and turtles have flippers, frogs and ducks have webbed feet, water boatman has oar-like legs.

Most fish have swim bladders to help them stay afloat or buoyant in water.

Activity: Share with pupils that, like modern day animals, prehistoric marine animals also had structural and behavioural adaptations in order to survive in the water. Get pupils to click on the interactive timeline at the website provided and explore the prehistoric marine animals according to the periods they existed in or by the continents they lived in. Read the short

write-up and study the 3D model of each animal. Discuss the adaptations special physical features or behaviours — that

helped these animals survive in their respective habitats. Describe some of the challenges that the prehistoric marine animals faced. Have pupils share their findings with the class.

Explain that: Adaptations are important for animals to survive, move and protect themselves.


21st Century Skills: Communicate clearly; Interact effectively with others; Think creatively

Adaptation for breathing in waterBackground: All living things need oxygen. Land animals take in oxygen from the atmosphere, while aquatic animals can

Textbook page 65Textbook pages 65—66

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Elaborate:Pupils expand their knowledge by watching the video

either make use of oxygen from the atmosphere or oxygen dissolved in the water.

Teaching Tip: Draw the following table to summarise the characteristics of adaptations for breathing in water.

Adaptations for breathing atmospheric oxygen Adaptations for breathing oxygen dissolved in water Blowholes located on top of their heads to help them

breathe when they are swimming near the water surface, e.g. whale, dolphin

Nostrils at the tip of their snouts; the nostrils are shut when underwater and breathing occurs only when the nostrils are out of the water, e.g. seal, walrus

Breathing tubes that stick out of the water surface to take in atmospheric oxygen, e.g. water scorpion, mosquito larva, mosquito pupa

Carry air bubbles in their adapted wings, legs or hairy bodies, e.g. water spider, water beetle

Gills that help to extract oxygen from the water and release carbon dioxide back into the water, e.g. fish, prawn, tadpole

Special thin layer of skin to help them breathe in the water, e.g. frog, flatworm, salamander

Gill chambers to store water and keep the gills wet all the time so the animal can use oxygen from the water in the gill chambers, e.g. mudskipper, hermit crab

Activity: Show pupils a video of how birds breathe. Explain to pupils that mammals and birds have slightly different ways of breathing. As flying uses a lot of the birds’ energy, they need a much more efficient respiratory system than mammals. Hence, they have developed lungs with numerous air sacs (usually nine air sacs) through which air circulates. This continuous flow of air maximises the efficiency of gas exchange to provide plenty of oxygen which is vital to ensure the proper functioning of the heart, muscles and brain during flight. Ask pupils: How do birds take in air? (Answer: They take in air through their nostrils.) Compare flightless birds with those that can fly. Do you think they breathe in different ways? (Answer: No, both flightless

birds and birds that can fly breathe in the same way using their lungs.) Do you think a penguin breathes the same way as an eagle? (Answer: Yes, both a penguin and an eagle breathe in the

same way using their lungs. The only difference lies in that a penguin is able to hold its breath for a much longer time than an eagle because it needs to dive underwater to catch fish. )

Explain that: The bird's highly-developed respiratory system works very well with its four-chambered heart, which is similar to that of

mammals.

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Explore:Pupils apply what they have learnt to design and create something that can fly

Process Skills: Observing, Inferring, Communicating

21st Century Skill: Think creatively

Adaptation for flightTeaching Tip: Draw the following table to summarise the characteristics of adaptations for flight.

Adaptations for flight Most flying animals have strong wings, e.g. birds, insects. Most flying animals have light body weight, e.g. bats, birds, insects. Birds that fly have powerful flight muscles to enable them to flap their wings. Most birds that fly have light feathers that keep the muscles warm so they can work effectively. They also

have large wing feathers to increase the surface area so they can stay in the air by gliding. Birds that fly have bones with hollow air spaces to reduce body mass. Some flying animals have modified limbs with sheets of skin covering the limbs to act like wings, e.g. bat,

flying squirrel, flying frog. Many flying animals have a streamlined body, e.g. birds.

Project Idea: Divide pupils into groups of four or five and get them to design an object that can fly by recycling materials that they can find in the classroom or in their home. Encourage them to read up beforehand about the adaptations of birds to help them fly and discuss how they can then apply these to their project. After they are done with designing, get them to suggest further improvements that could be made to their model. The winner would be the group that is able to keep their object in the air for the longest time.

Process Skills: Observing, Inferring, Hypothesising

21st Century Skills: Think creatively; Reason effectively; Use systems thinking; Solve problems; Interact effectively with others; Manage projects

Adaptation for coping with extreme cold Background: Adaptations are used to cope with physical conditions of the environment which include temperature, light, water, air and food. Temperature changes affect animals and how they adapt to stay alive.

Teaching Tip: Draw the following table to summarise the characteristics of adaptations for living in extreme cold.


Workbook pages 55—56Activity 2: Best Body Shape


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Animals Adaptations for living in extreme coldWalrus It does not have much hair on its tough skin but has thick layers of fat (blubber) to keep it warm.Polar bear It has thick layers of fat under its skin. Its thick fur traps air close to its body, and the air and layers of fat

act as insulators to protect the animal against cold temperatures. The polar bear has black skin and white fur. Its black skin absorbs heat, but its white fur reflects heat. Hence, when a polar bear gives off heat from its body, the white fur reflects the heat back to the skin and the black skin absorbs the heat, keeping the bear warmer. It has a small nose and ears as well to reduce heat loss.

Penguin Like Arctic birds, it has a coat of fine feathers and a layer of fat under its skin to keep it warm.Grizzly bear It hibernates to survive in the winter months when the environment becomes too cold and food is scarce.

When it hibernates, life processes such as respiration and digestion slow down to conserve body heat and energy.

Musk ox It has a thick fur coat to keep it warm in the winter. It also huddles with several of its kind in a circle with the calves in the middle. This way, it conserves body heat and is also able to protect its calves from predators.

Arctic tern It migrates southwards to warmer regions before winter arrives to find food elsewhere and to escape from the cold.

You can show pupils pictures of the animals above as you describe the adaptations of each animal.

Teaching Strategy: Giving examples

Adaptation for coping with extreme heat Ask pupils: What are the conditions of a desert environment during the day and at night? (Answer: The desert is extremely hot and

dry in the day and extremely cold and dry at night. The extreme fluctuations in temperature are due to a lack of cloud cover to retain heat when night falls.)

What adaptations might animals have for living in hot places? (Answer: Accept all reasonable answers, such as having large ears to dissipate heat, having a coat or body covering that is pale in colour to absorb less heat, being active only at night when it is cooler, etc.)

What adaptations might animals have for living in dry places? (Answer: Accept all reasonable answers, such as being able to go without water for long periods of time, producing little sweat or urine to conserve water, etc.)

Teaching Tip: Draw the following table to summarise the characteristics of adaptations for living in extreme heat.

Workbook pages 57—58Activity 3: Surviving the Cold!

Workbook page 73Worksheet 3: Home for the Winter


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Explain: Pupils learn the correct concept to prevent any misconception

Engage: Pupils carry out an experiment and test their predictions

Animals Adaptations for living in extreme heatCamel It has a thin body covering that shields and insulates it from the scorching heat in the day in the desert. It

drinks a lot of water at a time, and sweats and urinates very little to prevent water loss.Fennec fox It has big oversized ears that have a large surface area to help it get rid of excess heat.Giraffe It drinks water when available but can survive for weeks without it. It relies on morning dew and the water

content in the leaves it feeds on. Other animals in the savannahs have very similar adaptations — they can go without water for a long time, e.g. the elephant and the zebra.

Wallaroo It has furry pads on the underside of its feet to help it climb rocks and search for water.

You can show pupils pictures of the animals above as you describe the adaptations of each animal.

Teaching Strategy: Giving examples

Common Misconception: Many people think that camels store water in their humps. Actually, fat is stored in camel humps. The fat can be broken down into energy and water to sustain the camels when food or water is scarce.

Project Idea: Explain to pupils that the surface temperatures of desert soil can be extremely hot. Desert vegetation is sparse and cloud cover is minimal. Thus, the soil is exposed directly to the heat from the Sun. About half of the Sun's heat is absorbed by the first few inches of soil and the other half is reflected back into the atmosphere. The temperature of the soil is also worsened by the low humidity — there is little water to evaporate and thus dissipate the heat. While desert daytime temperatures may be high, night-time temperatures may drop dramatically. Heat from the Sun rapidly warms the soil and air during the day, but then escapes rapidly into the atmosphere at night due to the lack of clouds in the sky. Desert animals have adapted to hot and dry conditions in a number of ways. They avoid the hot desert ground by resting in the shade of a bush, on branches above ground, or in underground burrows. Adopting a nocturnal lifestyle is another way to avoid the heat and conserve body fluids.

Divide pupils into groups of four or five and get them to discuss the best way of carrying out an experiment, using the given materials, to find out how temperature varies with the depth of sand. Ask them to think about what measurements they should take and how to ensure that the experiment is fair. Guide them to carry out the following experiment.

Materials

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Empty milk carton Ruler Marker Scissors or penknife 2 thermometers Sand Lamp

Procedure1. Mark an empty milk carton at a height of 7.5 cm and 15 cm measured from the bottom. Cut a slit at each mark, large

enough to insert a thermometer. 2. Insert a thermometer in each slit.3. Fill the open carton completely with sand. 4. Position a lamp directly over the top of the sand. 5. Record the initial temperatures on both thermometers and record them in a table. 6. Next, turn on the lamp. 7. Record the temperatures at each level in the table after 10 minutes, 20 minutes and 30 minutes have passed. 8. Repeat the experiment two more times. Be sure to let the sand cool off before carrying out the experiment again.

Ask pupils: From your observations, were the initial temperatures at both levels the same? (Answer: Yes, they were the same.) From your observations, how does the temperature at each level change with time? (Answer: For both levels, the

temperature increases with time. However, there is a greater increase in the temperature nearer the surface of the sand than nearer the bottom.)

What is the relationship between the depth of sand and its temperature? (Answer: The greater the depth of sand, the lower the temperature.)

Why would desert animals live in burrows? (Answer: They live in burrows to look for shade and avoid the heat given off by the desert soil nearer the surface.)

Process Skills: Observing, Contrasting, Inferring, Hypothesising

21st Century Skills: Think creatively; Reason effectively; Interact effectively with others

Adaptation for obtaining food Background: Animals must be able to get food to feed themselves and their young in order to survive.

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Explore:Pupils discover how animals adapt to find their food

The table below lists some common structural and behavioural adaptations animals have to obtain food.

Structural adaptations for obtaining food Behavioural adaptations for obtaining food Birds have different kinds of beaks that suit their own

feeding habits, e.g. the flesh-eating eagle and owl have powerful and sharp beaks; the seed-eating parrot and macaw have short, thick, strong and pointed beaks.

Some animals have adapted feet to assist them in obtaining food, e.g. the hawk has sharp and powerful curved claws for catching and holding prey.

Some animals have sharp, pointed teeth called fangs to help them tear flesh apart, e.g. tiger, wolf.

Some animals have teeth to help them cut and grind grass, e.g. cow, zebra.

Some animals have long and sticky tongues that can capture insects flying near them, e.g. frog, lizard.

Some animals hunt in pairs to make catching prey easier, e.g. lion, leopard.

Some animals hunt in groups, e.g. wolves. Some birds fly very high to spot prey that are a distance

away, e.g. hawk, eagle.

Activity: Get pupils to carry out Discover More! Ask pupils to do an Internet search to find out other adaptations that animals have to obtain food. Then, list them down and classify them into structural and behaviourial adaptations. Find out if there are any animals that have both structural and behavioural adaptations to help them obtain food.

Process Skills: Observing, Analysing

21st Century Skills: Apply technology effectively; Work independently; Be self-directed learners

Adaptation for protection from predators Background: Animals that are prey must be able to protect themselves from predators in order to survive.

The table below lists some structural and behavioural adaptations of animals to protect themselves from danger.

Structural adaptations for protection from predators Behavioural adaptations for protection from predators Tough body covering to protect themselves from

predators, e.g. crocodiles have scales, turtles have Hiding, e.g. tortoises hide inside their shells. Living in groups, e.g. deer form herds.


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Explore:Pupils discover how animals adapt to protect themselves against their predators

Explore:Pupils discover how animals engage in different courtship displays

shells and hedgehogs have spines. Warning colours to indicate to predators that they are

poisonous or bad-tasting, e.g. coral snakes and poison dart frogs are brightly-coloured.

False features to make them look bigger or more frightening to predators, e.g. some moths have eyespots on their wings.

Camouflage, e.g. cuttlefish can change colour to match their surroundings, leaf insects and stonefish have a body shape and structure that allows them to blend with the surroundings.

Moving away quickly from danger, e.g. squid force out a jet of water to help them swim away quickly.

Changing appearance, e.g. pufferfish appear bigger and spiky when threatened.

Distracting predators, e.g. lizards can drop off their tails and the tails wriggle to distract their predators.

Teaching Tip: Show a video about the adaptations certain animals have to protect themselves against predators.

Adaptation for reproduction Background: Reproduction ensures the continuity of a species. In order to reproduce, animals need to mate. Those that are more successful in attracting mates have better chances of reproducing.

The table below lists some adaptations for reproduction in animals.

Structural adaptations for reproduction Behavioural adaptations for reproduction Colourful body coverings, e.g. peacock Parts of their bodies can light up to attract a mate, e.g.

glow worm

Makes mating calls, e.g. frog Showing off to attract a mate, e.g. peacock displays its

feathers, frigate bird vibrates its throat sac, claps its bill and waves its wings

Activity: Ask pupils to visit the website and use the information there to write a report about the different courtship displays that animals engage in to attract potential mates.

Process Skills: Observing, Inferring, Contrasting, Communicating

21st Century Skills: Reason effectively; Communicate clearly; Work independently; Be self-directed learners

Activity: Get pupils to carry out Discover More! Ask pupils to do an Internet search to find out other adaptations that animals

URL 4.3


URL 4.4

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Engage: Pupils are tasked to carry out a show-and-tell session

have to protect themselves against predators. Then, list them down and classify them into structural and behaviourial adaptations. Find out if there are any animals that have both structural and behavioural adaptations for protection from predators.

Process Skills: Observing, Analysing21st Century Skills: Apply technology effectively; Work independently; Be self-directed learners

Activity: Get pupils to carry out Build Your Skills! Divide pupils into groups of four or five and get each group to choose an animal and discuss how it survives in its habitat. Encourage pupils to think about what adaptations the animal has to move in its environment, obtain food, escape from predators, reproduce and cope with environmental changes in its habitat. Then, get pupils to present their findings to the class in the form of a show-and-tell session.

Teaching Strategy: Show-and-tell


21st Century Skills: Reason effectively; Collaborate with others; Interact effectively with others; Communicate clearly

Textbook page 79


Internet links for Lesson 4.2

URL 4.1: Interactive Timeline for the film ‘Sea Monsters: A Prehistoric Adventure’http://www.nationalgeographic.com/seamonsters/timeline/index.html#introduction

URL 4.2: Video of how birds breathehttp://projectbeak.org/adaptations/internal_breathing.htm

URL 4.3: Video of the adaptations certain animals have for protection against predators http://www.youtube.com/watch?v=6Gq4pFjWemE

URL 4.4: Courtship displayhttp://www.bbc.co.uk/nature/adaptations/Courtship_display

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http://www.bbc.co.uk/nature/adaptations/Courtship_display

http://www.youtube.com/watch?v=6Gq4pFjWemE

http://projectbeak.org/adaptations/internal_breathing.htm

http://www.nationalgeographic.com/seamonsters/timeline/index.html#introduction



Engage:Pupils are introduced to the topic with an activity

Explain: Pupils learn about the different

How Are Plants Adapted to Their Environment?Activity: Display and label pictures of three environments on the board: desert, pond and tropical rainforest. Give pupils 10 minutes to draw or name plants they think can be found in these three environments. Then, ask pupils to share with their partners what plants they have drawn or named and how they think each plant is adapted to its particular environment.

Ask pupils: What are the characteristics of plants found in each of the environments? (Answer: Accept all possible answers, such as

some plants found in deserts have waxy surfaces to reduce water loss; some plants found in ponds may have stems filled with air spaces to help them float; some plants found in tropical rainforests can grow up to great heights to ensure that they get sufficient sunlight.)

Explain that: These characteristics allow the plants to survive the conditions of their natural habitats. Each characteristic is unique to the adaptation of the plants to enable them to adapt and survive in their environment.

Process Skills: Observing, Inferring, Analysing, Communicating

21st Century Skills: Think creatively; Reason effectively; Be self-directed learners

Adaptation for obtaining sunlight Background: Most plants have strong woody stems to hold them upright to reach for sunlight. Plants with weak stems, however, have adaptations to help them obtain sufficient sunlight. Climbers climb up a support using tendrils (e.g. cucumber) or clasping roots (e.g. money plant) to reach for sunlight. Creepers (e.g. sweet potato) have long and thin stems that spread out on the ground horizontally. These stems cover a large area of the ground to enable the plants to get more sunlight.

Adaptation in water plants Background: As the amount of sunlight entering the water decreases with increasing depth, aquatic plants have special adaptations to help them obtain sufficient sunlight.

Teaching Tip: Draw the following table to summarise the characteristics of adaptations of water plants.

Type of plant Adaptations

Textbook page 79


Textbook page 81

Workbook pages 59—60Activity 4: Help Me Float!

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adaptations that pond plants have

Explore:Pupils discover the adaptations that pond plants have to help them stay afloat

Floating plants Plants such as water hyacinth have spongy and swollen leaf stalks that contain air spaces to keep the plants afloat so that the leaves get plenty of sunlight.

Partially submerged plants Plants such as arrowhead have leaves that grow above the water surface to obtain sunlight. Water lilies have large waxy leaves that float on the water surface to get sunlight.

Completely submerged plants Plants such as hydrilla, elodea and cabomba have tiny air spaces in their leaves and stems to help them float as near as possible to the water surface so that they can obtain more sunlight.

Activity: Get pupils to carry out Discover More! Visit the website to find out more about how the hairs on the leaves help some pond plants such as the water lettuce to stay afloat. Pupils can also find out what other adaptations pond plants have to help them stay afloat.


21st Century Skills: Apply technology effectively; Work independently; Be self-directed learners

Adaptation in desert plants Background: Many desert plants are dull and gray. The leaves of some plants, such as sagebush, are covered with tiny hairs. These hairs reflect the rays of the Sun and protect the leaves from being dried out by the wind. Other plants, such as the rabbitbrush, have very small leaves as big leaves would allow too much water to escape through evaporation due to the large surface area. Whenever the water supply is plentiful in the desert, the prickly pear cactus collects moisture in the spongy tissue of its enlarged stems, called pads. The cactus can then draw on this stored supply of water when the weather turns dry.

Adaptation for dispersing seeds Background: Dispersal is necessary because new generations of plants cannot easily occupy the same physical space their parents occupy. Otherwise, overcrowding would result and the plants would compete with one another for space, water, light and minerals. Unlike most animals, plants have limited abilities to seek out favourable environments. Consequently, plants have evolved adaptations for dispersal by means of seeds, spores or vegetative outgrowths.

Many plants produce large numbers of seeds to ensure that enough of them will settle at favourable sites. Plants have evolved dispersal mechanisms that take advantage of various forms of kinetic energy, including gravity, wind, the flow of water and the movement of animals. There is also ballistic/mechanical dispersal, whereby a seed pod explodes open and flings its seeds far away from the parent plant.

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Evaluate: Pupils’ understanding of plant adaptations is assessed through this fun charade

Teaching Tip: Show pupils a video of the various methods of seed dispersal.

Adaptation for pollination Background: Flowers need to be pollinated. Pollination is the process of moving the pollen grain from the anther of a stamen to the stigma of a carpel. There are a few flowers that can self-pollinate on their own, but this limits them to in-breeding. Most species rely upon some kind of pollinator to accomplish pollination. The pollinator can be any agent that can move pollen from anther to stigma. Water or wind function as the pollinators in certain species, but many species do not depend upon the random or downstream-only pollination pathways offered by these vectors. Indeed, such pollinators are only useful in situations where large populations of a very limited number of species are present. Most species are pollinated insects, although birds and bats may also be pollinators in some species.

Teaching Tip: Show pupils a video of the adaptations which plants have for pollination to occur.

Project Idea: You can use this activity as a review of plant adaptations. Review the concept of adaptations and how plants have adapted to their surroundings.

Divide pupils into groups of four or five. Assign each group a description of a plant adaptation to act out. Each group will have five minutes to plan how they will act out the description. Then, each group will act out their description in front of the rest of the class. The other groups can call out or raise their hands to guess the specific adaptation. Points can be awarded to the group with the correct answer. You can mention examples of plants with the specific adaptation or award bonus points to the group which can give an example of a plant with the specific adaptation.

Some suggested plant adaptations and their respective examples:• Plants with prickly thorns to repel animals that feed on them (e.g. prickly pear, mesquite)• Plants that orientate themselves towards or away from the Sun (e.g. compass plant, some sunflowers)• Plants with seed pods that disperse their seeds by explosive action (e.g. peas, lady’s finger, orange-spotted touch-me-not,

bluebonnet, jewelweed, Ruella (Mexican petunia), oxalis (wood sorrel))• Plants with waxy surfaces to protect them from water loss (e.g. cacti, agave, yucca)• Plants with flower parts that deposit pollen on visiting insects (e.g. foxglove, bluebonnet)• Plants with hairy parts to protect them from extreme heat and cold (e.g. bluebonnet, Indian blanket)• Plant parts that stick to animals so they can be carried to new places for the plants to grow (e.g. Texas star seeds, grass

burr seeds, beggar’s ticks seed pods)• Plants that cause itching to keep predators away (e.g. stinging nettle, poison ivy)


URL 4.6

Textbook page 85

URL 4.7

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Engage: Pupils are tasked to carry out a show-and-tell session

21st Century Skills: Think creatively; Reason effectively; Interact effectively with others; Collaborate with others

Activity: Get pupils to carry out Build Your Skills! Divide pupils into groups of four or five and get each group to choose a plant and discuss how it survives in its habitat. Encourage pupils to think about what adaptations the plant has to obtain sunlight, disperse seeds, attract pollinators and cope with its environmental conditions. Then, get pupils to present their findings to the class in the form of a show-and-tell session.

Teaching Strategy: Show-and-tell

Process Skills: Analysing, Observing

21st Century Skills: Reason effectively; Collaborate with others; Interact effectively with others; Communicate clearly

Workbook pages 69—70Worksheet 1: Living in Heat and Under Covers

Workbook pages 71—72Worksheet 2: How Have I Adapted?


Internet links for Lesson 4.3

URL 4.5: How some pond plants float (corresponds with Internet Link 4.1 in Textbook) http://pondutah.wetpaint.com/page/Floating+Water+Plants

URL 4.6: Seed Dispersal http://www.youtube.com/watch?v=zbQ1jWl3AOM

URL 4.7 Flower Pollination http://www.youtube.com/watch?v=ge3EM8AERV0

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http://www.youtube.com/watch?v=ge3EM8AERV0

http://www.youtube.com/watch?v=zbQ1jWl3AOM

http://pondutah.wetpaint.com/page/Floating+Water+Plants



Elaborate: Pupils reinforce their knowledge about the relationship between an organism’s habitat and its adaptations

How Are Different Organisms Suited to Their Habitats?Pond habitatBackground: All animals are physiologically adapted to their particular environment. Therefore, pond organisms have developed specialised structures to enable them to breathe, move, obtain food and otherwise survive in an aquatic habitat.

Teaching Tip: Using the table below, prompt students to think about how some organisms move in the water, highlighting the links between habitat, diet and movement.

Part of the pond

Organism What it eats How it moves Adaptation

Above the surface

Duck Pondweed, insects, snails, larvae, tadpoles, small fish

Flies, dives and paddles

Wings, waterproof feathers, webbed feet

Adult dragonfly/mayfly

Insects Flies, hovers Two pairs of wings, streamlined shape

Pond edge Frog Plants, algae, dead matter, insects

Jumps, swims Muscular legs, webbed feet

Newt Dead plants and animals Crawls, skates across water surface

Long-splayed legs, water-repellent hairs

Mid-water Fish Plants, water fleas, tadpoles, shrimp

Swims Gills, fins, streamlined body

Tadpole Plants, insects, dead matter

Swims Gills, tail, streamlined body

Great diving beetle Water fleas, snails, water boatmen, larvae, leeches

Walks, dives and swims

Streamlined body, fringed jointed legs

Water boatman Shrimp, worms, tadpoles Rows using legs

Paddling legs, hair-lined body traps air

Leech Snails, larvae, tadpoles Swims Sucker, flattened bodyDragonfly/mayfly larval stages

Small fish, water fleas, shrimp, tadpoles, micro-

Swims, crawls Gills on abdomen

Textbook page 86Textbook pages 86—87

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Evaluate: Pupils’ understanding is assessed through a game of bingo

organismsBottom of the pond

Freshwater worm Micro-organisms, dead and decaying matter

Swims Haemoglobin, thin body wall, segmented body

Water flea Rows using antennae

Antennae, flattened body

Freshwater shrimp Swims Side-flattened body, swimming legs, gills

Activity: Make copies of the bingo sheet found in Appendix 1 and hand them out to pupils. Explain the rules of the game. You will describe an adaptation of a particular pond animal and how this unique characteristic helps it to survive in an aquatic habitat. Pupils must cross off the animal described from their bingo sheet. Pupils should shout ‘Bingo!’ when they have a full column (vertical, not horizontal) of crossed-off animals. The first pupil to get a full column of correctly identified animals wins. The winner must call out the animals that make up the winning column to ensure each animal was matched to its adaptation correctly.

Clues you can use when playing this game: This animal is able to breathe air through a breathing tube attached to its tail, which punctures the water surface, acting

like a snorkel. (Answer: Mosquito larva) This animal has long, thin, splayed legs allowing it to walk upon the surface of the water, taking advantage of the water

surface tension. (Answer: Pondskater) This animal is red due to the haemoglobin in its blood, which carries oxygen transferred across the skin through diffusion.

(Answer: Freshwater worm) This animal has oar-like side swimming legs and breathes underwater by carrying an air bubble trapped by the hairs that

line its body. (Answer: Water boatman) This animal has a side-flattened body and swims on its side using five pairs of swimming legs which propel water across its

gills. (Answer: Freshwater shrimp) This animal has gills that allow it to breathe underwater and a streamlined body and tail to help it swim as it looks for

plants or insects to eat. (Answer: Tadpole) This animal has a streamlined body and fringed jointed legs allowing it to move very fast as it dives through the water to

hunt its prey. (Answer: Great diving beetle) This animal has a flattened body and moves in the water by rowing its antennae. (Answer: Water flea)


21st Century Skills: Think creatively; Reason effectively

Appendix 1

21


Engage: Pupils are given questions to stimulate thinking and generate interest in the new topic

Green habitatAsk pupils: What is one difference in the environment between a pond and a garden? (Answer: Accept all possible answers, such as a

pond is wetter than a garden.) Can the orchid plant survive in the pond habitat for long? Why? (Answer: No, the roots of the orchid plant will rot if they

are exposed to too much water.) Can the frog survive in the garden habitat for long? Why? (Answer: No, the frog needs to keep its skin wet to prevent it

from drying out. Besides, the frog lays its eggs in water. It cannot survive nor reproduce in the garden habitat.)

Explain that: Different types of organisms are suited to specific habitats. This is why changes in the environment of a natural habitat

can have adverse effects on the organisms living in it.

Wrap up the chapter with the following:

Talk It OutTeaching Tip: Read the new words out loud and have pupils repeat each word after you so they can learn to pronounce the words correctly. Then, have pupils pair up to test each other on the meaning of the words.

Map It OutTeaching Tip: Go through the concepts with pupils after finishing the chapter. Trace the path of the mind map by reading out aloud. You may wish to draw the map as you speak. Plants and animals have adaptations to obtain air, food and water, protect themselves from predators, reproduce and

cope with changes in the environment. Adaptations can be structural or behavioural. Animals have adaptations for breathing in water, moving in water, flight, coping with extreme cold and heat, obtaining

food, protection from predators and reproduction. Plants have adaptations for obtaining sunlight, obtaining water, dispersing seeds and pollination.

Work It OutGo through the worked example with pupils. Read the hint when answering the question.

Process Skills: Analysing, Predicting


Workbook pages 61—66Activity 5: Great Adaptations

Workbook pages 67—68Activity 6: Out of Place


Fun and Games

Exam Practice

Textbook page 89

Textbook page 90

Textbook page 91

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Explore: Pupils discover how Man can apply the adaptations of animals for our own benefit

Science @ WorkTeaching Tip: To boost pupils’ reading and speaking confidence, have pupils take turns reading the passage, e.g. each pupil could read one paragraph. Encourage pupils to read with enthusiasm and emotion.

21st Century Skill: Think creatively

Textbook page 92

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Documents

· Web viewPlants such as hydrilla, ... Teaching Tip: Read the new words out loud and have pupils repeat each word after you so they can learn to pronounce the words correctly