- •Unit 1
- •Skeletal System
- •Bones
- •Long bones have long longitudinal axes and expanded ends. Examples are the arm and leg bones.
- •Short bones are somewhat cube like, with their lengths and widths roughly equal. The bones of the wrists and ankles are examples of this type.
- •Functions of Bones
- •Skeletal parts provide shape, support, and protection for body structures. They also act as levers that aid body movements, house tissues that produce blood cells and store various inorganic salts.
- •Joints of the Skeletal System
- •The Plan for Rendering the Text
- •Unit 3
- •1 Learn the key words and phrases:
- •2 Match the terms to following definitions:
- •the gap between the ends of the broken
- •bone
- •4) the remains of something broken
- •down or destroyed
- •5) a rigid dressing of gauze impregnated
- •with plaster of Paris for immobilizing a
- •diseased or broken part
- •Fractures
- •Repair of a Fracture
- •Meanwhile, phagocytic cells begin to remove the blood clot as well as any dead or damaged cells in the affected area. Osteoclasts also appear and resorb bone fragments, thus aiding in "cleaning up" debris.
- •Unit 5
- •Muscular System
- •Muscles, the organs of the muscular system, consist largely of cells that are specialized to undergo contractions. During these contractions, chemical energy from nutrients is converted into mechanical energy, or movement.
- •Atrophy and Hypertrophy of Skeletal Muscles
- •Pre-text assignments
- •Digestive System and Digestion
- •Unit 10
- •The Alimentary Canal
- •Unit 11
- •Stomach
- •Unit 12
- •Heart
- •Unit 19
- •Actions of the Heart
- •Unit 20
- •Blood Vessels
- •Unit 21
- •Paths of Circulation
Digestive System and Digestion
The human body needs energy for its functioning. Our body assimilates proteins, fats, carbohydrates and other nutrients. The digestion of the starchy parts of food begins in the mouth where it is moistered with saliva. In the tongue papillae (lingual papillae) there are the taste receptors. Over the mucous membrane of the oral cavity there are many tactile, temperature and pain receptors. The teeth, the gums, the soft and hard palates and the salivary glands are important structures located in the oral cavity. In the oral cavity the food must be well chewed between the teeth. Then the food passes through the pharynx (throat) and down through the esophagus (gullet) into the stomach which is a dilated portion of the alimentary truct pyriform in shape. The stomach is composed of a fundus (upper part), a body (middle part) and an antrum (lower, distal part). The upper opening of the stomach is called the cardiac sphincter and the lower one – pyloric. The folds in the mucous membrane lining the stomach are called rugae.
In the stomach the components of food are dissolved and hydrolysed by enzymes of saliva and gastric juice. Different gastric glands are found in the stomach. They produce hydrochloric acid and pepsin to digest food. The gastric juice secreted by the stomach possesses antibacterial activity. Pepsin converts proteins to smaller substances called peptones. But food does not enter the bloodstream through the stomach.
Further digestion and absorbtion of food into the blood takes place in the small intestine. After portions of the stomach contents enter into the duodenum they turn acid, but then the reaction rapidly changes because the hydrochloric acid of the gastric juice is neutralized by the bile, the juice of the pancreas, the juice of the duodenal glands and intestinal crypts. The bile comes from the liver and gallbladder by means of special ducts. The pancreatic juice, a colourless clear fluid contains sodium, potassium chlorides and is rich in enzymes which digest proteins, fats and carbohydrates.
Food passes in peristaltic waves from the duodenum to the jejunum and the ileum, which is attached to the large intestine. The entire
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small intestine has many projections called villi. It is in the small intestine where the so-called cavital.and membrane hydrolyses of nutrients takes place. The products of digestion are absorbed into the blood and lymph.
The remaining part of food (the fluid by-products of digestion) from the small intestine pass into the large intestine which consists of cecum, colon (ascending, transverse, descending), sigmoid colon and rectum. The vermiform appendix hags from the cecum. The rectum ends in the anus. The process of digestion is completed in the large intestine by the absorption of water. The unabsorbed and undigested components of food, the remains of the digesting fluids are evacuated from the body.
Post-text assignments
1 Choose the anatomic terms for the following:
1 The organ of chewing and tasting. 2 The movable muscular structure attached to the floor of the mouth; an important organ in the articulation of speech sounds. 3 The muscular membranous cavity leading from the mouth and nasal passages to the larynx and esophagus. 4 The roof of the mouth. 5 The tube through which food passes from the pharynx to the stomach. 6 Any of numerous hairlike or fingerlike vascular processes in the small intestine. 7 The first section of the small intestine between the stomach and the jejunum. 8 A large, elongated gland: some cells (beta cells) islets of Langerhans in the gland produuce the hormone insulin. 9 The largest glandular organ which secretes bile. 10 The organ for containing food and digestion of it.
(a – palate; b – duodenum; c – stomach; d – pharynx; e – esophagus; f – mouth; g – tongue; h – liver; i – pancreas; j – villus (pl villi)
2 Say what organ is spoken about:
a) This organ is the largest gland in the human body. It is in the upper part of the abdominal cavity under the diaphragm in the right side of the abdomen. Its upper surface is convex. This organ consists
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