Humans Breathe

When we breathe, we inhale(take in) and exhale(let out) air. How can we tell? Our chest move up and down. The number of chest movement is the rate of breathing.

As we inhale, the chest rises outwards and upwards causing the chest to expand. The air is taken in through the nose, down the windpipe into the lungs. This air contains more oxygen. 

As we exhale, the chest moves in causing the chest to contract. The air inside the lungs then flows out from the lung to the windpipe and then out through the nose.This air contains more carbon dioxide. 

Answer the questions.

1. Name P and Q.

    i) P: lung                                         ii) Q: windpipe

2. What is P used for?

    P is used for breathing.

3. What is Q used for?

   Q is used to let the air flows into and out from the lungs.

A Complete Change

Many young animals do not look like their parents. They undergo changes before they look like their parents. Can you name the animals?

                                   Stages in the life cycle of a butterfly

                                       Stages in the life cycle of a frog

From tadpoles to frogs

Rearrange the pictures to show the sequence of each animal's life cycle.

                               Arrangement: ( Q ) - ( P ) - ( S ) - ( R )

                               Arrangement: ( Y ) - ( Z ) - ( W ) - ( X )

Living in Extreme Weather

Animals

Cold Weather

Do you know the name of animals that live in very cold weather?How do they survive?

Polar bears have thick furs to enable them to live in very cold weather.

Penguins have thick layers of fat under their skins to keep their bodies warm.

Arctic foxes sleep during cold weather and cover their bodies with their long tails.

Hot Weather

Camels have humps on their backs to store food and water. They can drink as much as 200 litres of water a day.

Rhinoceroses keep their bodies cool by wallowing in mud holes.

Fill in the blanks with the correct answer.

1. Which animal can survive in hot weather?

    Animal P and Q.

2. Which animal can survive in cold weather?

    Animals R.

3. What are the characteristics of the animals above that help them to   survive in the kind of weather mentioned in Questions 1 and 2?

   i)  P : Has humps to store food

  ii)  Q : Thick skin

 iii)  R : Thick fur

The Solar System Song

The Sun

Do you know that the Sun is a star?

There are billions of stars in the Universe like the Sun. The Sun is the center of the Solar System and it is the closest star to the Earth! The Sun gives us light, heat, and energy.

Mercury

This is the planet Mercury.It is the closest to the Sun. The temperature is too hot to support life.

Venus

A great amount of the heat from the Sun is trapped in its atmosphere. This makes it hotter than Mercury.

Earth

Earth is the third planet from the Sun. It has water, air and a suitable temperature to support life.

Mars

 

Almost all of its water is frozen. Scientists have not found any life there.

Jupiter

Jupiter is the fifth planet from the Sun. It is the biggest planet in the solar system. It is a huge ball of hot liquid and it is surrounded by thick clouds of gas. These gases form coloured bands around the planet.

Saturn

Saturn surrounded by three flat rings that are made up of bits of ice and rocks. They can be seen with a telescope.

Uranus

Unlike the other planets, Uranus is lying on its side as it goes round the Sun.

Neptune

Neptune is covered with a blue ocean of liquid methane.

Pluto

Pluto is very cold because it is very far from the Sun.

Answer the questions below.

(a) Name the planets:

     i.   V  =  Venus                                   iv.   Y =  Saturn

    ii.   W =  Earth                                    v.    Z =  Pluto

   iii.   X =  Jupiter

(b) Which of the planets has living things?

      W

(c) Comment your answer in (b).

      W is the planet Earth

(d) Predict the planet that has a ring around it.

      Saturn

Solar System

We live in the Solar System.

Our Solar System has nine planets, plus asteroids (pieces of rocks) and comets (frozen balls of dust and gas) that circle around the Sun.

Comets

A comet is a large ball of glowing gases, dust and ice. There are billions of comets circling around the Sun. When a comet gets near the Sun, the sun's heat melts some of the frozen gas. Bits of rocks and metals stream off into space. These form a glowing tail when the Sun shines on them.

Meteors

A meteoroid rushes through space at tremendous speed. When it enters the Earth's atmosphere, it robs hard against the air and becomes so hot that it burns up, leaving behind a trail of glowing gas. We call it meteor. Seen from the surface of the Earth, burning meteor looks like a bright streak of light flashing across the sky like a shooting star.

Asteroids

Asteroids are tiny planets that circle the Sun in a ring between Mars and Jupiter. The larger asteroids are ball shaped. But the smaller one are bumpy and jagged. Sometimes asteroids bump into each other and break up into smaller rocks. These rocks are called meteoroids.

The diagram shows one of the constituents of the Solar System

(a) Predict the name of the object P.

     Comet

(b)Give reason to support your answer in (a).

     A comet consists of two parts which looks like a head and a long tail.

(c)What causes object P to appear as a flying lighted object?

     A comet does not produce light but its constituents of dust and gases reflect light from the Sun.