Реферат на тему:
The human body
The human body consists of three parts. They are the head, the trunk
and the limbs. There are many bones of different sizes and shapes in the
skeleton. The bones are connected together by the cartilages, the
ligaments and joints. The joints allow the bones to move.
The main part of tin; head is called the skull. The bones of the skull
are composed of cranial and facial parts. The skull encloses the brain.
The forehead, the temples, the cheeks, the cheekbones, the two jaws and
the mouth compose the face. The teeth and the tongue are lodged in the
mouth. One chews food with the teeth and tastes food with the tongue.
The lips are the two margins of the mouth. We see with the eyes, breathe
and smell with the nose and hear with ears.
The trunk consists of the spine, the chest and the pelvic bones. In the
spine there are many vertebrae. They are cervical, thoracic, lumbar,
sacral vertebrae and the соссух. The trunk is divided into two large
cavities by diaphragm. The upper cavity of the trunk is called thorax
and the lower one is called the belly. In the middle of the thorax (the
chest) there is a long bone the breastbone by name. The ribs are
connected with the breastbone by cartilages, the lungs and the heart are
located above the diaphragm in the upper cavity. In the lower cavity
(abdominal cavity) we find interior organs such as stomach, liver,
urinary bladder, gallbladder, kidneys, spleen and intestines (bowels).
There are two nipples on the chest, and, in women, the breasts with the
teats. There is the navel in the middle of the abdomen. At the lowest
part of the abdomen there are genitals (the external reproductive
The upper limb (extremity) is divided into the shoulder, the upper arm,
the forearm and the hand. The joint between upper arm and forearm we
call the elbow. The wrist is the joint between forearm and hand. Each
hand has five fingers: index (fore-finger), middle finger, ring finger,
little finger and a thumb.
The lower limb consists of the thigh-bone (the femur), the shin-bone
(the tibia) and the fibula. We call the calf the back of the lower leg.
The joint between the femur and the lower leg is called the knee-joint.
This joint is protected by the knee-cap (the patella). The joints
between lower legs and feet are the ankles. The foot consists of heel,
sole and toes.
The muscles form about 40 per cent of the body weight. They are
subdivided into three groups. These groups are the muscles of the trunk,
head and extremities. There are about 600 skeletal muscles. As far as
their form is concerned they can be long, wide and short. The long
muscles compose the free extremities, the wide ones lay, on the trunk
and form the walls of the body cavities. The short muscles are not
numerous. Some of them form facial muscles. Muscles are attached to
bones, internal organs and blood vessels. They allow us to make an
internal or external movement due to their contraction and relaxation.
As for the structure of the muscles there are also three types of them:
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