XII. Define what nouns are substituted, render from English into Russian:

1.The axial skeleton forms the body’s central alignment; its bones are primarily those of support and shelter

2.The appendicular skeleton “hangs from” the axial skeleton; its bones are primarily those of movements

3.Long bones, such as those in the arms and legs, function as levers for the skeletal muscles to generate movement and locomotion

4.The compact construction of short bones, such as those in the hands and feet, supports functions that require greater strength.

5.Diffusion gradients are maintained by ventilation, which renews alvedar air, maintaining oxygen concentration near that of atmospheric air.

6.When a weak signal is sent by the CNS to contract a muscle, the smaller, motor units, being more excitable than the larger ones, are stimulated first.

XIII.Find in the text English equivalents to the following word- combinations:

иначе могли бы тереться друг об друга; расположены внутри (оболочки) капсулы; вызывая износ и разрыв; между пластинами черепа

XIV. Read and translate the text:

Joints, tentons, ligaments and bursa

Joints are the junctions between two or more bones. Some joints do not normally move, such as those located between the plates of the skull. Other joints allow a large and complex range of motion. The configuration of a joint determines the degree and direction of possible motions. The components of joints provide stability and reduce the risk of damage from constant use. In a joint the ends of the bones are covered with cartilage – a smooth, tough, resilient, and protective tissue composed of collagen, water, and proteoglycans that reduces friction as joints move. Collagen is a tough fibrous tissue. Proteoglycans are substances that provide the resilience of a cartilage. Joints also have a lining synovial tissue. It encloses joints to form the joint capsule. Cells in the synovial tissue produce a small amount of synovial fluid, which provides nourishment to the cartilage and further reduces friction while facilitating movement.

Ligaments are tough fibrous cords composed of connective tissue that contains both collagen and elastic fibres. The elastic fibres allow the ligaments to stretch to some extent. Ligaments surround joints and bind them together. They help strengthen and stabilize joints, permitting movement only in certain directions. They also connect one bone to another.

Tendons are tough bands of connective tissue composed mainly of a rigid protein called collagen.

Tendons firmly attach each end of a muscle to a bone. They are often located within sheaths, which are lubricated to allow the tendons to move without friction.

Bursas are small fluid-filled sacs that can lie under a tendon, cushioning, the tendon and protecting it from injury. Bursas also provide extra cushioning to adjacent structure that otherwise might rub against each other, causing wear an

tear.