Body movements chapter condensed notes.

1. BODY MOVEMENTS

2. WHAT DO YOU MEAN BY BODY
MOVEMENTS?
 Human beings exhibit locomotion. Locomotion is brought about by the
combination of muscular and skeletal system. The bending and movement
of the skeleton is brought about by special structures called as joints.
Joints along with muscles can bring about movement in bones. One end of
the muscle is attached to a movable bone and the other end of the muscle
is attached to a fixed bone.
 Muscles are attached to bones by tough cords called as tendons.
 Muscles work in pairs and bring about movement by contraction and
relaxation.

3.  The paired muscles are biceps and triceps which together help in the movement of
the structures like arm, leg etc.
 Contraction brings in the shortening of the muscle and relaxation brings about
lengthening of the muscle. It makes the muscle short, thick and stiff to pull the
bone .
 When the arm is folded, biceps contract and triceps relaxes and lengthens.
 When the arm is straightened, biceps relax and lengthen whereas triceps contract.

4. HUMAN BODY AND IT,S MOVEMENT.
 Human skeleton consists of 206 pieces of bones. The bones are associated with
each other with the help of either joints or sutures. Joints help in movement.
Skeletal system is classified into two groups namely :
(a) Axial skeletal system.
(b) Appendicular skeletal system.
Axial skeletal system
It consists of bones of skull, vertebral column and chest bone.

5.  Skull
The skull is the bony framework of the head. The upper part is made up of 8 flat
bones joined together (cranium bones). The face and jaw contains 14 bones (facial
bones). It protects the brain and sensory organs.

6.  Vertebral column
It is made up of 33 ring-shaped bones which are called vertebrae. It is flexible,
and runs from skull to pelvis. It holds the heads body upright.
It protects the spinal cord and keeps the body erect.
 Chest bones
It is also called rib cage. There are 12 pairs of ribs that curve around from the
spine to the front of the body. The ribs are attached to the sternum(or the breast bone).
It encloses the lungs and heart and takes part in breathing.

7.  Vertebrae

8.  Appendicular skeletal system
It consists of two pairs of girdles and bones of arms and legs.
(a) (b)

9.  Girdles
The bones that are found in the shoulder form the pectoral girdle. It protects the
heart and lungs. It also provides attachment for the upper arm.
Find the bones in your body that is generally called the hip. These bones form
the pelvic girdle. The pelvic girdle protects the reproductive organs. They also
provide attachment to the lower limbs.
 Bones of arms : In the upper arms, there is only one bone, humours. It exactly fits
into the cavity in the pectoral girdle. On the lower side, it has a broad surface
which is connected to two and bones, radius and ulna of the lower arm.

10.  Bones of legs : The bone present in the thigh, femur is the longest bone of the
body.it has a ball shaped head that can be fitted into a cavity formed by pelvic
girdle. The lower end joints the lower part of the leg. The lower leg is made up of
two bones – tibia and fibula.

11.  Joints
The location where two or more bones meet is called a joint. Ligaments bind a bone
to another bone. Tendons bind a bone to a muscle.
 Types of Joints
 Fixed joints: The joints where no movement of bones is possible are called fixed
joint. The joints in the skull bone (cranium) are examples of fixed or immovable
joints.
 Moveable joint: Movement is possible in these joints. There are two types of
movable joints:

12.  There are four types of movable joints in the body; which are as follows:
 Ball and socket joint: In this joint the rounded end of one bone fits into the cavity
(hollow space) of another bone. It permits movement in all directions. The joints
between shoulder and the upper arm is an example of ball and socket joint.
Similarly, the joint between thigh and hip is an example of ball and socket joint.
 Pivot Joint: This type of joint allows movements in many planes, viz. up and
down, side to side movements. The joint between the skull and the vertebral
column is an example of pivot joint.

13.  Hinge joint: This joint is similar to the hinges in a door. This joint allows
movement only in one plane and only up to 1800. The knee joint and elbow joint
are examples of hinge joint.
 Gliding joints: The movement in this joint happens due to sliding of bones over
one another. Joints between the rings of the backbone are examples of gliding
joint. The wrist joint is also an example of gliding joint.

14. A SKELETON SYSTEM

15. THANK YOU
BY GAGANDEEP.M