M0Vent

Q1. Write the functions of human skeleton.
Ans. The functions of human skeleton are   :-
  1. It supports the body by giving a framework and gives a definite shape.
  2. It protects the several delicate organs such as brain, kidney, heart, spinal cord, lungs etc.
  3. It helps in movement and locomotion.
  4. It gives a leverage   movement by the joints which increases the speed of the movement.
  5. It helps in the formation of blood such as white bone marrow makes the white blood cells while the red bone marrow makes red blood cells.
  6. Bone is a storehouse of calcium and phosphorous.

Q2.What does the human skeleton consist of?
Ans. It consists of bones, cartilages, tendons and ligaments.
Q3.Define:-
  1. Declacified bones:-
Ans. When the bone is kept in weak hydrochloric acid {HCl} it removes its calcium and phosphate such   a bone is called decalcified bone. It is soft and flexible.
2. Oxidized bones:-
Ans. If the bone is burnt in the air it loses its organic matter while the mineral part is left. Such a bone is called oxidized bone which is brittle and can break easily. Generally old people in their old age loose their organic part of the bone hence the bones becomes weak and become fragile which can break easily.
Q4. Write in short the structure of a bone.
Ans. The structure of bone is as follows:-
  1. Bone is a highly calcified hard and rigid connective tissue.
  2. It consists of bone cells called oesteocytes.
  3. These cells have collagen fibers, deposits of calcium and phosphorous.
  4. The external surface of the bone is covered with a membrane called periosteum. While the inner layer is richly supplied with blood vessels.
  5. Bone has white {white blood cells} and red {red blood cells} bone membranes.

Q5. Write the shapes of bones and their location.
Ans. The shapes of the bones and their location are as follows:-
  1. Long bones:-present in arms, legs and ribs.
  2. Short bones:-present in ankles and...