Forms of life

Mammals are covered by hair orfur, have a backbone and are warm-blooded.

哺乳动物被毛发覆盖，有脊骨，是温血动物。

All female mammals produce milk for their young.

Reptiles are covered byscales, and include snakes,lizards and turtles.

Reptiles have a backbone and are cold-blooded, which means they often rely onexternal sources of heat.

Birds are covered byfeathersand are warm-blooded.

Most birds can fly and many types of birdsmigrategreat distances.

Mostinsects such asants andbees have a small, 3-part body with 3 pairs of legs.

Some insects, like mosquitoes,spread diseases that cause the deaths of many humans.

Unlikeanimals, plants get the energy that they need from the sun.

Plants convertlight energy along with carbon dioxideand water into chemical energy.

Most mammals live on land, but some live in the sea.

Insects don't have a backbone, and most are cold-blooded.

Instruments

Scales and rulers are used to measure weight and length.

Units of weight includes kilograms and pounds and units of

length includes centimeters and inches.

These instruments are used to observe very large and very

small objects.

Telescopes are used by astronomers and microscopes are

used by biologists and doctors.

These appliances are used in the kitchens of almost every home.

Stoves are used to heat food and refrigerators are used to

keep foods cool or cold.

Household tools like these, are used to build and repair things.

Hammers are used to pound in the nails and screwdrivers

are used to turn a screw.