Third Grade Science Support Study Guide

Process Skills

These are the six process skills we will use to explore in science:

Observe: Use your five senses to find properties of objects.

A scientific observation is one that anyone can make and the result will always be the same.

An unscientific observation is an opinion which may not be agreed upon by everyone.

Classify: Group objects according to similar properties. Sometimes it is necessary to classify by two properties.

This is an example of classifying eggs by two properties.

________________________________________________

Sometimes we classify objects or events in a special order.

Objects or events can be put in order by a property like size, shape or color. Another way to place objects or events in order is by which happened first,

second or third. 1

The kitten is black and white. I used my sense of sight to

observe the property of color. This is an example of a scientific

observation.

The kitten is cute. This opinion is an unscientific observation.

Predict: A prediction is an idea about what will happen in the future and an explanation of why it will happen.

I predict it will rain because it is cloudy outside.

Measure: When we measure, we use tools to make an observation about an object.

Tool Use Picture

Beaker, Graduated Cylinder, Graduated Syringe

To measure volume of liquids Milliliters (ml) Liters (l)

Meter Tape, Meter Stick, Ruler

To measure length, width, height, or distance Centimeters (cm) Meters (m)

Forceps, Tweezers To pick up small objects

Tuning Fork To make vibrations

which make sound

Balance To compare mass of

objects Grams (g)

Thermometer To measure

temperature Fahrenheit (oF) Celsuis (oC)

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Infer: To draw a conclusion from data in graphs, tables, and diagrams. An inference is an explanation made without actually observing the object or event.

Communicate: Scientists use graphs, charts and diagrams to share information. The bean plant graph above is an example of the way scientists communicate.

Safety Rules should be followed during science experiments

Wear safety equipment like aprons or goggles when needed. Be careful with sharp objects and glass. Only the teacher should clean up broken

glass. Do not put anything in your mouth unless your teacher tells you to do so. Follow all directions for completing the science investigation. Follow proper handling of animals and plants. Keep your workplace clean and clean up after investigation. Follow all the safety instructions for each investigation Tell the teacher about accidents or spills right away. Be careful when working with hot objects or heat sources. Wash hands after each activity.

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A good inference from observing the graph above is that the older the

bean plant gets, the taller it grows.

A Scientific Investigation

The steps in a scientific investigation are:

Ask a testable question to be investigated. A testable question is one in

which an investigation is needed to find the answer.

Make a prediction (possible answer to the question).

Decide what materials are needed for the experiment.

List steps to carry out the experiment. Remember that only one factor can

change. All others must be kept the same.

Record observations and organize the data during your experiment.

Communicate the results and infer meaning from your data.

Example of a science investigation

Paper Towel Test

Question: Will Bounty brand or school brand paper towel absorb the most water?

Prediction: We predict that Bounty will absorb the most water because it feels softer

and thicker.

Materials: Bounty paper towels, School brand paper towels, two 100 ml beakers,

Water, Pencil, Paper

List of steps: 1. Cut paper towels to 5 inch by 5 inch squares.

2. Place 80 ml of water into 2 beakers

3. Dip store brand paper towel into one beaker and Bounty brand paper

towel into the other until soaked.

4. Lift from water and drip for 15 seconds.

5. Measure the amount of water left in the beaker and subtract it from

the 80 ml of water you started with.

6. Record your data.

7. Repeat procedure two more times.

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Results: The chart shows the amount of water absorbed by each paper towel.

Brand of Towel Test 1 Test 2 Test 3

Bounty 50 ml 57 ml 61 ml

School Brand 22 ml 28 ml 26 ml

Conclusion: We were correct. In all three tests, Bounty absorbed more water.

Only one thing changes in a project. This is what is being tested. For example, in the

project above, the brand of paper towels is the only thing that changed. The size of

the paper towels stayed the same. The amount of water in each beaker stayed the

same. The amount of time each paper towel was allowed to drip stayed the same. So

what is being tested is the absorbency of the brands of paper towels.

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Earth’s Materials and Changes

Rocks – objects made of 2 or more minerals

Sedimentary rock: Usually made up of pieces of rock called sediment that have

been pressed and cemented together. Some have fossils. Sandstone and limestone

are examples of these rocks.

Things to remember… Made by layers of sediment…The word sediment is in the word sedimentary.

Fossils are found in sedimentary rocks because when plants and animals die, they become part of the sediment (broken up rocks, minerals, soil) and the dead plants and animals are buried along with the sediment.

(you can see the layers)

Sedimentary rocks are made of layers and sediment and some have

fossils. You can sometimes see stripes of the different minerals and

layers.

Igneous Rock: Made from cooled lava. Igneous rocks may be glassy or grainy with crystals of different sizes. Granite is an example of Igneous rock.

Igneous rocks are very likely to be found around volcanoes.

Metamorphic Rock: Was once either a sedimentary or igneous rock. Heat and pressure caused the minerals to change in the rock…creating a

metamorphic rock. .. Rocks that have pressed down could have minerals line up in rows or bands. Marble and Slate are examples of metamorphic rocks. Things to remember Metamorphic rock is known as “changed rock” Made by heat and pressure deep underground

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Metamorphic rock was once sedimentary or igneous and was changed by

heat and pressure.

Some rocks that are Natural Resources:

Natural resources – objects found in nature that man uses Ores are rocks that contain a lot of metals Coal is a rock that can be used as fuel. Oil can also be used for fuel. Granite is used in building. Sand is used to make glass.

Minerals

Minerals – solid, nonliving materials found in the earth, that have properties we

can use to identify them.

Ways to Identify Minerals

Hardness

Hardness refers to whether the mineral can be scratched or can scratch something else.

The harder the mineral, the fewer the things that can scratch it. The hardness is numbered 1-10 with 1 being the softest and 10 being the

hardest. Diamond is the hardest mineral.

Hardness is how hard or soft a mineral is.

Color

Color can be used along with other properties to help identify a mineral. Since many minerals have the same color, it cannot be used as the only property

for identification.

Color alone cannot identify a mineral.

Luster

Some minerals are very shiny, pearly, metallic, or glassy and other minerals are dull.

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Example Quiz Question: A student notices that a mineral shines in the light.

What property is being observed?

*Be able to answer question using identification key

Example Quiz Question: Which mineral has a hardness of 2 and is dull?

Gypsum

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Fossils

Fossils are molds, casts, or preserved parts of things that lived long ago and turned into rock. They are important because they help us to learn about what the world was like long ago.

Fossil Mold : A cavity or opening in a rock that has the shape of once living things.

Fossil imprints of leaves and other thin objects, such as wings, feathers, and footprints

are also molds.

The mold is the hole left by either a footprint or the animal that died and

rotted away. The mold is the hole the shape of the once living thing.

Fossil Cast: A mold that has been filled in with sediments which harden and take the

shape of the once living thing. It has the shape of the real thing!

An animal dies and rots away, leaving the shape of its body (a mold).

Sediment fills the mold and hardens, taking the shape of the once living

thing. This is the cast.

Preserved parts: Actual parts of the living thing such as shells, bones, or teeth that

have turned to stone. For example, sometimes an insect long ago was trapped in tree

sap. That sap hardened into a rock called amber. The insect was preserved in the

amber stone.

Preserved fossils are the actual plants or animals that get trapped in tree

sap and are preserved…they do not rot or decay.

Fossil Fuels

Fossil Fuels are fossils that we can burn for energy to heat homes and power cars. It was formed from the remains of plants and animals that lived long ago.

Coal is a solid fossil fuel. Petroleum oil is a liquid fossil fuel that we make gasoline from.

Classify Soils

Humus

Humus is soil that is made up of decayed (rotten) parts of once-living organisms. It is dark, soft, and very crumbly.

The rotten things contain nutrients that plants need to “eat”.

Humus is really good for growing plants because the decayed plants

and animals put nutrients back into the soil.

Sand

Sand has large grains with large spaces between the grains. This lets water leave it quickly. Sand feels gritty.

Clay

Clay has very small grains, much smaller than sand or silt, and holds water easily. This makes clay sticky when wet, but when it dries, it forms hard clumps. It is packed together so tightly that plant roots have a hard time breathing Silt

Silt has pieces that are smaller than sand. It feels like powder. Silt is found around rivers and lakes Loam

Loam is a mixture of soils made with sand, silt and lots of humus. Loam is dark and rich for plants to grow in. In the chart below you can see that loam is best for plants because it has air for plant roots, lots of humus for plants to “eat” and holds water for plants to “drink”.

Type of Soil Has Humus A Lot of Air Hold Water

Loam yes yes yes

Sandy Soil no yes no

Clay yes no yes

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Natural Resources

Fuels

Earth materials come from inside Earth and are used as fuels. For example, fuels such as oil and coal can be burned to produce heat or made into

gasoline to help run cars and other vehicles.

Rocks and Minerals as Building Materials

Earth materials can be mined from Earth and used to make building blocks or other building materials.

For example, granite, marble, and sandstone have been used to make blocks for homes and office buildings.

The mineral calcite is used to make cement for building.

Soil for growing plants

Earth materials can be used for growing plants. For example, soil is made up of weathered pieces of rocks, minerals, and humus

which supply water, nutrients and support for growing plants. Different types of soil are needed depending upon the type of plants that need to grow in the soil.

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Processes that change the Earth Gradually or Slowly

Weathering

When weathering is occurring, Earth Materials, for example rocks, are being broken apart.

Weathering is caused by water, wind, ice, temperature, and plants.

Weathering is a SLOW change to Earth.

Erosion: When erosion is occurring, Earth materials, like rock, sand, and soil, are

being carried away from their original location. Water and wind are often causes of

erosion.

Erosion is a slow change to Earth. The Grand Canyon was created by

erosion.

Deposition: Earth material that has been carried away by erosion and dropped off in

a new location. When winds stop blowing, sand and soil may be put down in piles as

large as dunes. Water may deposit its material at the end of a river and form a delta.

Think “deposit” is when something is dropped off. Deposition is a SLOW

change to the Earth’s surface.

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A chant to remember:

Weathering will break rocks down

Erosion moves it all around

Put it here and then we’re done

Now we have Deposition

Processes that change the Earth Rapidly or Fast

Landslides

When a landslide is occurring, Earth’s materials, like rock, sand, and soil, on the side of a slope or cliff drop down to a lower location. Water soaking into the ground often makes this happen.

Landslides are a FAST change to the Earth’s surface. Wet soil and

earthquakes can cause landslides.

Volcanic eruptions

When a volcanic eruption is occurring, Earth material called lava comes out of the volcano and flows down the side of the mountain. This lava hardens forming new land or making the volcano larger.

Volcanic eruptions are a FAST change to Earth’s surface.

Floods

When a flood is occurring, a lot of water causes rivers and streams to overflow, surrounding land around them. Heavy rainfall in the area is usually the cause of a flood.

Floods are a fast change to Earth’s surface.

Earthquakes

When an earthquake is occurring, the surface of the ground shakes and rolls causing damage to the Earth’s surface, like cracks and other openings, and damage to roads and buildings. Earthquakes cause the Earth to change fast.

Earthquakes are fast processes that cause the ground to shake.

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Saltwater and freshwater features:

Glacier - a huge area of moving ice.

Oceans - large areas of salt water that cover over 75% of the earth

Sea- a body of salt water that is not as large as an ocean

River - a large, moving stream of fresh water

Stream – a small, moving stream of fresh water

Lake – a large body of fresh water that is almost totally surrounded by land

Pond – a small body of fresh water that is almost totally surrounded by land

Land features:

Mountain - a very high place on the earth’s surface that has a pointed or

rounded top. Older mountains have rounded tops. Younger mountains have

pointed or jagged tops.

Volcano - a mountain that is formed when lava and other materials pour out of

an opening in the ground.

Valley - a low area between mountains.

Canyon – a deep valley with steep sides often with a stream flowing through it

Cavern – a cave that is large and mostly underground

Island – a small area of land surrounded by water but not large enough to be a

continent.

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Heat and Changes in Matter Study Guide

Mass

Mass is how much matter is in an object. Mass can be measured with a tool called a balance. An object with large mass feels heavier than an object with smaller mass.

Volume

Volume is the amount of space an object takes up. Volume of liquid can be measured with a beaker, graduated cylinder or a

graduated syringe. An object that takes up more space has greater volume.

Matter

Anything that has mass and volume

The three types of matter you will need to know are: solids, liquids and gases. Properties of matter that can be used to describe matter are either observable

(using your 5 senses) or measurable (using tools)

Observable (using senses) Properties

Measurable (using tools) Properties

Using Sight: Color, size, shape, shininess or luster Using Touch: texture, hotness or coldness Using Smell: odor or no odor

Balance for measuring mass Beaker, Graduated Cylinder or Syringe for measuring volume Thermometer for measuring temperature Ruler for measuring length

Solids

Have a definite volume and shape Volume and shape do not change easily

Liquids

Have a definite volume but they take the shape of their containers

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A baseball has more mass than a cotton ball. The baseball will feel heavier.

An elephant has more volume than a mouse. The elephant takes

up more space than the mouse.

A rock is an example of a solid. Its volume and shape stay the

same.

Milk is an example of a liquid. Its volume stays the same

but its shape will change depending upon what container it

is in.

Gases

Do not have a definite shape or volume Take the shape and volume of their container

State of Matter Definite Volume Definite Shape

Solids Yes Yes

Liquids Yes No

Gases No No

Melting

Melting happens when a solid is heated enough to change to a liquid. When solid ice melts, it changes to liquid water. Ice melts at Oo Celsius or 32o Fahrenheit

Freezing Freezing happens when a liquid gets cold enough (heat is removed) to form a

solid. When water freezes, it changes to solid ice. Water will expand (or have greater volume) when it freezes; other substances

contract (have less volume) when they freeze. Water freezes at Oo Celsius or 320 Fahrenheit.

Boiling Boiling changes a liquid to a gas quickly with bubbles of gas forming in the liquid

because a lot of heat is being added. Water boils at 100o Celsius or 212o Fahrenheit. When substances are heated they will expand and take up more space.

Celsius Temperatures 30o C is hot 200 C is nice 10o C is cold

0oC is ice

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Air is a gas. It takes the shape and the size of the

container it is in.

Snow will melt when the temperature outside rises above

32 degrees Fahrenheit.

The water puddle will freeze to ice when the

temperature falls below 32 degrees Fahrenheit.

Evaporation Evaporation happens when liquids change to gases because heat is added.

The water in this pot is evaporating into the air.

Condensing (Condensation)

Condensation happens when a gas is cool enough (heat is removed) to form a liquid.

Heat Heat can be made by rubbing, burning or using electricity. Rubbing: For example, when hands are rubbed together, they get warmer. Burning: For example, when wood is burned by fire, it makes heat. Using Electricity: For example, when electricity is used in light bulbs, it makes

heat.

Conductors Objects that allow heat to move easily through them and from one object to

another through contact are conductors. Metal and glass objects are good conductors of heat.

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When liquid water can be seen on the outside of a glass

of ice tea, condensation happened because the water

vapor in the air came into contact with the cold glass.

The pan is a conductor. It allows heat to pass from the stove

through the bottom of the pan in order to cook the eggs.

Insulators Insulators do not allow heat to move easily through them. They block the flow of

heat. Wood, plastic and rubber are good heat insulators.

An oven mitt is an insulator. We are able to hold a hot pan and not get burned.

Motion and Sound Study Guide

Motion

Position: Where an object is located - above, below, inside of, underneath, beside and on top of

Distance

The length between two objects or positions Distance between objects can be measured using meter tapes, meter sticks or

rulers. Distance can be recorded in meters or centimeters.

Direction

The course or path along which something travels Terms that describe direction include: up, down, left, right, north, south, east

and west.

Speed

Speed is how fast an object moves. Faster objects move a greater distance than slower objects in a certain period of time

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The cup is on top of the table. The fish is inside of the fish tank.

In these sentences the words “on top of” and “inside of” describe

the position of the objects.

The distance between my desk and the door is ten meters.

The direction a train travels to get from South Carolina to New

York is North.

If the toy car moves a greater distance than the toy truck in one minute, then its speed is

greater.

Push or Pull

The stronger the push or pull, the faster the object will move. The weaker the push or pull, the slower the object will move. If the strength of the push or pull is the same, an object with greater mass (how

much matter is in an object) will move slower than an object with less mass.

Gravity

Gravity is a pull that attracts objects to one another. The pull of gravity is everywhere. Earth’s gravity pulls objects towards the center of the Earth. The pull of gravity holds things down on Earth. Things fall to Earth because they are pulled straight down by Earth’s gravity. No matter whether an object is dropped or thrown, it will always fall towards

Earth’s surface.

Sound

Vibrations

All sounds are caused by vibrations.

Vibrations are very quick back-and-forth movements. Vibrations can travel from one object to another causing that material to vibrate. Vibrations causing sound can travel through solids, liquids, and gases but not

through empty space where there is no matter to vibrate.

Pitch

Pitch of a sound is how high or low it is. The longer the object is, the lower the pitch. The shorter the object is, the higher the pitch.

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If your science book and a pencil were pushed with the same force, the book

would not move as far because it has greater mass.

Even though the football was thrown high in the air, it fell back to the

ground because of Earth’s gravity.

Strumming a guitar causes the strings to vibrate producing a

sound.

The straw that would make the highest pitch would be letter “C”…..the straw that would make the lowest pitch would be letter “A”…

The smaller drum would produce a higher pitch. The larger drum would produce the lower pitch.

Volume

The loudness or softness of sound It takes more force to create loud sounds than soft sounds.

Strength of Vibrations

Striking a drum with more force will create a louder sound than striking a drum with a less force.

If the force is decreased, volume becomes softer. If the force is increased, volume becomes louder.

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The sound from a person yelling is a louder volume than the sound of a person

whispering. The pitch can be the same.

Tapping drums lightly produces a soft sound, while hitting

your drums hard produces a loud sound.

Distance from Vibrating Object

If the vibrating object making sound is farther away, the volume of the sound is softer.

If the vibrating object making sound is close, the volume of the sound is louder.

Pitch of sounds can be changed in 3 ways:

Length of Vibration- Shorter objects vibrate faster than longer objects; the faster the vibration, the higher the pitch of the sound; When you shorten the length of a guitar string, it makes a higher pitch.

Thickness- thinner strings or wires vibrate faster than thicker ones, producing a

higher pitch. A thin rubber band will produce a higher pitch than a thick rubber band when plucked.

Tightness- the tighter the stretch of the string, the higher the pitch of the sound.

Tighter wires vibrate faster making the pitch higher.

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The TV will sound louder if you are in the same room as the TV. It

will sound softer if you are down the hall from the TV.

Habitats and Adaptations

Life Cycle of Seed Plants

Seed

· After pollination (the spreading of pollen from flower to flower) occurs, seeds are

produced and may be stored in fruits.

· Seeds contain tiny undeveloped plants and enough food for growth to start.

· Seeds need water and warmth to germinate (begin to grow).

The seed is the first stage of the life cycle of the plant.

Seedling

· Seedlings produce the parts of the plant that will be needed for the adult plant to

survive in its habitat.

· Roots begin to grow and take in nutrients and water from the habitat.

· The stem starts to grow towards light and the first leaves form on the stem.

· Later, more leaves will form that help the plant make its food.

The seedling is the second stage of the plant’s life cycle.

Mature Plant

· Mature plants have the same structures (for example roots, stems, and leaves) as

seedlings, but in addition they develop flowers or cones, which produce seeds.

The main difference between a seedling and an adult plant is the seedling cannot reproduce and doesn’t have flowers or cones like a mature plant.

The mature plant is the third stage of the plants lifecycle. The only

difference between a mature plant and a seedling, is the seedling cannot

reproduce more seeds.

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Life Cycles of Animals

Adults reproduce only the same type of animal. Cats have kittens, not puppies.

These 5 things are present in all animal life cycles: birth, growth, adulthood,

reproduction, and death.

Some animals are born alive and some animals hatch from an egg. Some animals

have all the parts at birth that adults have. Insects and amphibians have to undergo

metamorphosis to look like the adult (see below). As a general rule, the more “babies”

a species has at one time the shorter the life span of the species.

Type of

Animal

Kind of Birth Looks like

this at birth

Metamorphosis

Mammals Born alive

(echidna and

duck billed

platypus lay

eggs)

Same as parent no

Birds Hatched from

eggs

Same as parent no

Spiders Hatch from silk

sac

Same as parent no

Fish Hatch from

eggs

Same as parent no

Amphibians Hatch from

eggs

Look like fish Yes – 4 steps

Reptiles Hatch from

eggs (rattle

snake is born

alive)

Same as parent no

Insects Hatch from

eggs

nymph or larva Yes – 3 or 4

steps

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Metamorphosis

A beetle and butterfly go through complete metamorphosis: Egg, Larva, Pupa, Adult

Some animals go through incomplete metamorphosis: Egg, Nymph, and Adult

Adaptations

Adaptation: A characteristic that improves an organism’s ability to survive

Physical Adaptation: Can be a body structure that an organism has that allows it to

meet its needs in its habitat

Example-The quills on a porcupine allow it to defend itself.

Behavioral Adaptation: Can be an activity or action that helps an organism survive

in its habitat.

Example-Bears hibernate during the winter and birds migrate to warmer places

in the winter.

Things to remember

Physical adaptation has to do with a living thing’s body. Behavioral adaptation has to do with the way a living thing behaves or acts.

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Adaptations

This chart gives a few examples of adaptations.

Adaptation Purpose Helps with Type of

Lion’s teeth Ripping meat Helps it eat physical

Grasshopper’s

color

Hide in grass Camouflage physical

Male bird’s

color

Attract mate Continue

species

physical

Skunk’s odor Ward off

predator

Not being eaten physical

Eagle’s eyesight Find prey far

away

Catching prey physical

Bird’s nesting Have a home Shelter for

young

behavior

Zigzag pattern

of rabbit’s run

Confuse

predator

Not being eaten behavior

Bears

hibernating

Survival during

cold

Food supply behavior

Bird’s migration Get to warm

area

Food supply behavior

More Specific Animal Adaptations

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Hibernation (physical adaptation)

A resting state that helps animals survive in winter. During hibernation, the animal’s body processes, like breathing, slow down, and

they survive on stored food or fat. Many animals, for example insects, birds, reptiles and some mammals, eat a lot

of food in the autumn months to store up fat. Then they burrow into the ground or curl up under leaves, or hide themselves in

dens, safe from the winter cold and enemies. When the temperature rises in the spring, the animal wakes up and leaves its

hiding place.

Defense

· Some animals have special adaptations to protect themselves from being hurt, killed,

or eaten.

· These special defense mechanisms include physical adaptations such as quills and

claws, and behavioral adaptations such as taking flight, mimicry, playing dead,

spraying, and fighting.

Things to remember Mimicry is when an animal “mimics” or pretends to be something it is not, such

as a walking stick mimics a stick. Many animals play dead to protect themselves from predators.

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This “walking

stick” mimics

looking like a

stick.

Locomotion

In order for animals to find the resources they need for food, shelter, or space, they must be able to move around.

Animals have special structures for moving depending on where they live, for example above ground (swinging, climbing and flying), on the ground (crawling, walking, hopping), or in the water (floating, swimming and diving).

Movement

The movement of animals over the same route in the same season each year is called migration.

This behavior allows animals to take advantage of resources (like food or water) in one location when they run low in another location.

Migration is a behavioral adaptation

Food obtainment

· Animals have special structures used for getting food, for example the beaks of birds, mouths of insects, teeth, or claws that are shaped in different ways depending on the type of food they eat.

Camouflage

· Camouflage is a color or pattern that allows an animal to blend into its environment and protects it from being seen by its enemies or allows it to sneak up more easily on their food.

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Adaptations of seed plants

Adaptations of Seed Plants

Some plants have special structural adaptations for meeting their needs in their particular habitat. Some examples of plant adaptations to conditions in their habitat may be:

Roots

Roots take in water and nutrients from the habitat. They may also hold the plant in place and store food and water. Plants will survive where its roots’ size, length, and spread are adapted to the

habitat. · Some examples of root adaptations may be:

Water lilies have long roots that can take in nutrients from the muddy bottoms of ponds or lakes.

Cacti have roots that spread out close to the surface for living in dry habitats. Carrots and dandelions have a large, thick root that is longer than its other roots.

This long root helps the plant survive by reaching far underground to find water and to firmly anchor the plant.

Stems

Stems move and store water and nutrients in the plant. Stems also provide support and protection for the plant.

Some examples of stem adaptations may be:

Vines have stems that can climb and stick to various surfaces to ensure that the leaves are exposed to light.

Corn and sunflowers have stems that grow thick and strong but remain green and flexible so that they can grow toward the sun.

Trees develop woody stems to support their size and provide protection during their long life cycles.

Cacti have thick stems that store water when the habitat does not provide it. Some stems have thorns that provide protection. Leaves

Leaves produce food for plants in the presence of light. Each variety of plant will survive where its leaf size, texture, thickness, and

shape are adapted to the habitat.

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Some examples of leaf adaptations may be:

Water lilies develop wide leaves that allow them to float on the water to capture sunlight to make food.

Evergreen trees have leaves that are thin and those waxy needles to protect them from freezing and from losing water.

Flowers

Flowers often have special sizes, smells, shapes, or colors that attract organisms for pollination.

Color

Flowers come in a variety of shapes, sizes, and colors. Petals are colored and scented to attract insects and other creatures for the

purposes of pollination. The coloration of parts of some plants (for example berries, or flower petals)

makes them attractive to some animals (for example birds or bees). Fruit

Fruits are formed around the seed to protect it. Some examples of fruit adaptations may be:

Some fruits are moist and fleshy (tomatoes, grapes, or peaches). Fleshy fruits attract animals that eat them helping to disperse the seeds.

Others fruits are dry and/or hard (coconuts, walnuts or pea pods). Seeds

Some seeds begin to grow as soon as conditions allow for germination. Seeds have adaptations that allow them to be dispersed and also to have enough

food for the plant until it begins making its own food. Seed dispersal

Most plants produce a large number of seeds because most seeds do not survive.

In order to ensure that seeds will survive, they must be carried away (dispersed) from the parent plant.

Some seeds have hooks on them that allow them to attach to animal fur or clothes.

Some seeds are able to float in water. Some seeds are light and have wings or thin hairs that allow them to be carried

away by wind. Some seeds are eaten by animals and deposited in areas away from the parent

plants. 29

What is the purpose of a seed that has hooks? To stick to animal fur

Response to light

· A plant needs sunlight or some other light source to survive.

· It uses the light for the energy it needs to make its food.

· A plant always turns its leaves and bends its stems toward the light.

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Habitat

A habitat offers a range of conditions (water, air, food, shelter, space, or sunlight) that allow some organisms to live there. A habitat must provide the needs for energy, growth, and protection for a particular plant or animal.

The habitat for some animals and plants may cover a large area. Some examples may be:

grazing animals may need lots of space to get enough food birds fly from place to place to get food large trees will grow in areas where enough water is available for their growth

Other animals or plants have habitats that may be a small part of a larger

environment.

Some examples may be:

squirrels may make their nests in one tree in a forest some small insects may live under a fallen log in the forest orchid flowers live by hanging on trees found only in warm, wet areas water lilies live in ponds in the shallow water

Food Chains

A Food chain is a model that shows how energy is passed from one organism to another.

All organisms need energy to survive. Energy gives the organism its ability to move and do the things it needs to survive. In most habitats, the Sun provides the energy which is passed from plants to animals.

A food chain uses arrows to show the direction in which energy is passed and usually contains no more than six organisms.

Food chains have three types of organisms. The role of an organism can be

described by how it obtains its energy.

Producers

· Any green plant, which uses sunlight to make food for energy.

· Producers are the first organisms listed in a food chain. The Sun provides the energy for the plants.

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Consumers

· An organism (usually an animal) that obtains its energy by eating other organisms

(plants and/or animals).

Decomposers

An organism (for example worms, mold, or mushrooms) that obtains its energy by feeding on and breaking down dead plants and animals.

· Decomposers are often not listed in a food chain even though they are always the last link.

Things to remember

ALL food chain starts with a plant. Producers make their own food. Producers and Plants both start with the letter P. Consumers are anything that eat other organisms. Decomposers feed on dead plant and animal matter.

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Producer: A

plant Consumer:

Anything

that eats

other

organisms

Decomposer:

Breaks down

dead plants and

animals

How Habitats change

Basic needs within a habitat can keep only a certain number of plants and animals alive.

Changes in a habitat can affect the survival of a plant and animal. There are many changes that can occur within a habitat that would force the animals or plants to change or adapt to survive.

Habitat change can occur naturally. Some changes occur rapidly, for example, disease, fire, hurricanes, landslides, volcanoes, earthquakes, or changes in temperature or amount of rainfall (drought or flood) can change a habitat.

Some changes occur slowly, for example, the changes in a plant life due to changes in sunlight (grasses to shrubs to trees), or if erosion occurs, causing the soil to wear away, fewer plants will be able to survive. When these events happen, the habitat usually cannot provide the needs for the animals or plants to survive there anymore.

Humans can also cause habitat changes. For example, clearing land to build homes, buildings, or farmland can cause the animals in that area to have to move to another location for food or shelter. Plants that normally grow there would not find the conditions for their growth available anymore.

Other animals or plants could also move into a habitat taking up needed space and food.

If animals or plants cannot adapt to changes in the environment, extinction (loss of an entire group of organisms) of that type of animal or plant can occur.

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