When two or more than two electric cells are connected together in such a way that the positive terminal of one cell is connected to the negative terminal of the other, then we call it a battery. A simple connection showing the combination of two electric cells to form a battery is shown below:

Roots perform following functions in the plant:
(a) Roots absorb water and minerals from the soil.
(b) Roots hold the plant to the soil.
(c) Roots store food.

The two properties of a magnet are as follow
(i) A magnet has two poles, i.e. north and south.
(ii) It attracts magnetic materials like iron, nickel or cobalt.

The complete circuit diagram so that-the bulb glows is given below
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Here, the two phenomena we must check. One is the usage of conductors and the other is insulators which can stop the flow of electric current. We observe that the one end of screw driver is made up of metal and the other is made up of an insulator. Thus, electric current starts through one end but stops at the other end and hence, current cannot flow through it. Thus, bulb will not glow.

No, because reflection is the phenomenon in which light ray is sending back towards while travelling through mirror. If there is no source of light, no image will be formed and hence, we cannot see the image of ourself or any other object unless light source is there.

(a) A joint in which the rounded end of one bone fits into the hollow space of other bone is called ball and socket joint. It allows movements in all the directions. Joints between upper arm and shoulder, thigh and hip are examples of ball and socket joints.
(b) In skull, only the lower jaw is movable. All the other bones of skull are immovable.
(c) Our elbow cannot move backwards because the elbow has a hinge joint that allows movement in only one direction.

The part of plant which produces its food is the leaf. This process is known as photosynthesis.

a)
 
b)

c)

The two magnetic materials are :
(i) Iron (ii) Cobalt.
The two non-magnetic materials are :
(i) Leather (ii) Plastic

Fish has a spindle-shaped streamlined body. This shape of the body helps it to move in water. Fish use their muscular tail and fins for swimming.

Materials through which electric current cannot flow are called as insulators. For example: rubber.

Life is not possible without plants. We should save plants. Plants give us oxygen which is essential for life. They provide us raw materials for various purposes. They are the house of many birds and animals.

Arrangement of veins on the lamina of leaf is called venation. They are of two types:
(a)Reticulate venation
(b) Parallel venation

Heart and lungs are protected by the rib cage.

A fused bulb does not glow because in a fused bulb, the filament of bulb burns up and connection is broken or incomplete, so the current cannot flow.

No, all plants are of different sizes. According to their size, they are classified as herb, shrub and trees.

An electric switch is a device used to complete or break an electric circuit. Usually, it is manually operated.
Purpose of using electric switch: In 'ON' position, the switch allows the current to flow through the circuit. Thus, the circuit becomes a closed circuit. In 'OFF' position, the switch does not allow current to flow through the circuit. Thus, the circuit becomes an open circuit.
Examples: Electrical appliances such as fans, electric lamps, washing machines, juicer and mixer, TV radio, etc, have switches.

An electric cell consists of a cylindrical pot which is covered by a thick paper sheet.

It consists of two terminals. One is called positive terminal and the other is called negative terminal. The metal cap is the positive terminal and the metal disc is the negative terminal of the electric cell.
The production of electric current takes place due to the chemical reactions inside the cell. The chemicals are present between the outermost covering of the cell and carbon rod.

Wrong statements :
(a) Anther is a part of the pistil.
Correct statement: Anther is a part of the stamen.
(b) The visibleparts of a bud are the petals.
Correct statement: The visible parts of a bud are the sepals.
(d) Leaves perform the function of transpiration only.
Correct statement: Leaves perform the functions of both photosynthesis and transpiration.

Opaque objects do not allow light to pass through them. When an opaque object is placed in the path of light, then the light is obstructed by the object leading to the formation of a dark patch known as the shadow of that object, which can be taken on a screen placed behind it.
Shadow formation: To form a shadow, there must be (i) a light source (ii) a screen (iii) an opaque object placed between the light source and the screen. For shadow formation, we can follow the given steps
Step 1: Take an opaque object.
Step 2: Throw light on it from a light source.
Step 3: Put a screen behind the object. In this way, a shadow of an object can be obtained on the screen.
In this way, a shadow of an object can be obtained on the screen.

An electric torch is a device which is used as a lamp. It has two or more than two cells, a bulb and a switch.

So, when we slide the switch of electric torch, circuit becomes complete and bulb starts glowing, while on sliding switch back, circuit gets broken and bulb goes OFF.