The Gomel Medical Institute. We study anatomy. My visit to the polyclinic. The working day of a district doctor (Устные темы по английскому языку)

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which maintains milk production from the breasts , and growth hormone. The back (posterior) lobe of the pituitary stores two hormones: vasopressin, which is carried to the kidneys to help control water content; and oxytocin, which assists the contraction of the uterus during labor  and encourages the flow of milk from the breasts after the birth of a baby.

The pineal gland secretes melatonin, which may help regulate sexual development and menstruation.

Each of the adrenal glands, situated over the kidney, is divided into outer (cortex) and inner (medulla) region. The medulla makes the hormones adrenaline and noradrenaline, which help to prepare the body for “fight or flight” in responses to danger. The hormones of the cortex include steroids involved in the metabolizing of sugars and proteins and in balancing body water content.

The thyroid lies below the voicebox and secretes hormones that control the rate at which cells use nutrients, and the body burns and stores sugars. Attached to the back of the thyroid are the four parathyroid glands whose hormones regulate the amounts of calcium and phosphate in the blood.

The amount of glucose in the blood is governed by cells in the pancreas, situated beside the duodenum. The endocrine cells of the gland make two hormones: glucagons, which raises blood levels, and insulin, which decreases them. The gland also secretes digestive enzymes.

The sex glands – ovaries in a female and testes in a male – produce hormones that control the production of mature sex cells and help to determine a person’s total sexual development.

The most serious diseases affecting the endocrine glands are thyroiditis (an inflammation of the thyroid gland) and diabetes (a disorder in which the body can not make use of sugars & starches in a normal way). The science which studies the endocrine glands & the treatment of their diseases is called Endocrinology.

IMMUNE SUSTEM

Immunology is the study of body’s defense from infectious agents and other foreign substances in the environment. This defense includes a mechanical barrier (the skin), protective chemical substances in the blood and tissue fluids, and physiologic reactions to injury or infection.

The immune system has three major properties:

·  to recognize and distinguish a vast number of different molecules;

·  to respond vigorously against foreign substances;

·  to provide immunity from a disease.

The body’s ability to protect itself from a disease is called immunity. It may be natural or acquired. Natural immunity is genetically determined. Acquired immunity is active or passive. Passive immunity is only temporary. Active immunity is permanent and results from previously suffered disease or vaccination.

Immunogens or antigens are substances stimulating an immune response. Antibody is a substance produced in response to an infection. It combines with antigen and neutralizes it.

Complements, phagocytes, WBCs and others help to protect the body against a disease and infection.

Immune response is usually carried by body’s lymphatic system. It is a network of thin-walled vessels which drain lymph from between the body cells into the blood stream. Rounded small bean-shaped structures called lymph nodes form part of the lymphatic system. They have 3 main functions:

-  to filter out and destroy foreign substances such as bacteria

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