Class 7 Science Skeleton Joints and Muscles Textbook Question Answers , Fill in the blanks as well as additional QA.
[1] Choose the correct answers.
Ball and Socket joint is found in
- a) Shoulder and arm bone
- b) Elbow
- c) Upper jaw
- d) Wrist
Vertebrae are found in
- a) Skull
- b) Hands
- c) Backbone
- d) Fingers
Cartilage is found in
- a) Hands
- b) Ear
- c) Foot
- d) Skull
Hinge joint is found in
- a) Upper jaw
- b) Elbow
- c) Lower jaw
- d) Shoulder
[2] Correct and rewrite the following sentences
- a) Cartilage protects soft organs like brain and lungs from injury.
- b) Bones of the hand are connected to the Pelvic girdle. [pectoral girdle]
- c) The brain is protected by the rib cage. [skull]
- d) Bones and muscles together form the muscular system. [correct]
[3] Answer the following questions.
a) In which part of the body is the longest bone located in your body found?
a) The longest bone in the body, the femur, is located in the thigh.
b) What is the use of the backbone in the body ?
b) The backbone (vertebral column) provides structural support, enables flexibility, and protects the spinal cord.
c) Explain the joints found in the fingers and knee.
c) In the fingers, there are hinge joints that allow movement in one direction. The knee, on the other hand, has a hinge joint as well as a sliding joint, enabling both flexion and extension as well as some rotation.
d) Why can’t earthworms stand up straight like human beings?
d) Earthworms lack a rigid internal skeleton like humans, so they rely on the hydrostatic pressure of their fluid-filled body to support their shape. This fluid-based structure prevents them from standing up straight.
