Body Movements | Science 6th | Chapter 8 | Questions and Answers

JANDKNCERT | Science 6^th |

Body Movements | Science 6th | Chapter 8 | Questions and Answers

 

Chapter 8: Body Movements

 

Introduction

In the previous chapter, you learnt about, Getting to Know Plants, in which you learnt that plants are usually grouped into herbs, trees, shrubs, creepers, and climbers based on their height, stems, and branches. Roots absorb water and anchor the plant firmly in the soil. Stem conducts water and minerals from roots. Leaves prepare and provide food to the plant by the process of photosynthesis.

This chapter is about Body Movements. The following points will help you to understand this chapter easily.

•     Bones and cartilage form the skeleton of the human body. It gives the frame and shape to the body and helps in movement. It protects the inner organs.

•     The human skeleton comprises the skull, the back bone, ribs and the breast bone, shoulder and hip bones, and the bones of hands and legs.

•     The bones are moved by alternate contractions and relaxations of two sets of muscles.

•     The bone joints are of various kinds depending on the nature of joints and the direction of movement they allow.

•     Strong muscles and light bones work together to help the birds fly. They fly by flapping their wings.

•     Fish swim by forming loops alternately on two sides of the body.

•     Snakes slither on the ground by looping sideways. A large number of bones and associated muscles push the body forward.

•     The body and legs of cockroaches have hard coverings forming an outer skeleton.

•     The muscles of the breast connected with three pairs of legs and two pairs of wings help the cockroach to walk and fly.

•     Earthworms move by alternate extension and contraction of the body using muscles. Tiny bristles on the underside of the body help in gripping the ground.

•     Snails move with the help of a muscular foot.

 

Let us try to answer some questions taken from the NCERT Book of Science Class 6th. This Exercise is taken from the same book. You will also find answers of other chapters and classes on Free ncert solutions website here

 

Exercises

Q1. Fill in the blanks

a. Joints of the bones help in the ___________of the body.

b. A combination of bones and cartilages forms the ______of the body.

c. The bones of the elbow are joined by___________joint.

d. The contraction of the ____________pulls the bones during movement.

e. An adult human has _________bones where as a baby has more than _______bones.

f. In water birds, ___, _________ present help them to swim.

g. Amoeba moves with the help of _________.

 

Answer.

a. Joints of the bones help in the movement of the body.

b. A combination of bones and cartilages forms the skeleton of the body.

c. The bones of the elbow are joined by the hinge joint.

d. The contraction of the muscles pulls the bones during movement.

e. An adult human has 206 bones where as a baby has more than 300 bones.

f. In water birds, webbed feet, and waterproof feathers present help them to swim.

g. Amoeba moves with the help of pseudopodia.

 

Q2. Indicate True (T) and False (F) among the following sentences

a. The movement and locomotion of all animals, is exactly, the same. (False)

b. The cartilages are harder than bones. (False)

c. The finger bones do not have joints. (False)

d. The arm has two bones. (True)

e. Cockroach has an outer Skelton. (True)

 

Q3. Match the items in Column I with one or more items of Column II

 

Column I	Column II
Upper Jaw	Have fins on the body, have a streamlined body
Fish has an	outer skeleton, fly in the air
Ribs can	an immovable joint
Snail is	Protects the heart
Cockroach	Shows very slow movement

 

Answer.

 

Column I	Column II
Upper Jaw	Is an immovable joint.
Fish has an	Have fins on the body, have a streamlined body.
Ribs can	Protects the heart.
Snail is	Shows very slow movement.
Cockroach	Outer skeleton, fly in the air.

 

Q4. Answer the following:

a. What is a ball and socket joint?

 

Answer.

The ball and socket joint is a joint that allows movement in all directions. It is rounded like a ball and is found between the joint of the shoulder and arm, and thigh and hip.

 

b. Which of the skull bones are movable?

 

Answer.

The skull is made of many bones joined together. The upper jaw and lower jaw are also part of the skull. The lower jaw of the skull is movable.

 

c. Why can our elbow not move backwards?

 

Answer.

Our elbow has a hinge joint that allows only a back and forth movement of our arm therefore it cannot move backwards.

 

d. How many vertebrae join to form the vertebral column in a human being?

 

Answer.

The vertebral column of a human being is formed by 33 vertebrae.

 

e. What are the floating ribs?

 

Answer.

The last two pairs of ribs (11^th and 12 pairs) of the rib cage are known as floating ribs. They are only connected to the thoracic vertebrae, so they are also known as vertebral ribs. As there is no attachment present ventrally hence they are known as floating ribs.

 

Q5. What kind of movements are seen in

a. Earthworm

 

Answer.

The body of an earthworm is made up of many rings joined end to end. It has muscles that help to extend and shorten the body. It moves by the contraction and the expansion of these muscles.

 

b. Snail

 

Answer.

The movement of a snail is slow. It has a shell that has to be dragged during its movement that makes movement slow.

 

c. Cockroach

 

Answer.

Cockroaches walk and climb as well as fly in the air. They have three pairs of legs and two pairs of wings attached to their breast that help them to walk and fly.

 

d. Snake

 

Answer.

Snakes slither with the help of their body muscles. Their body curves into many loops and each loop push the body to move fast.

 

e. Birds

 

Answer.

Birds fly in the air with the help of their wings and walk on the ground with help of their hind limbs.