Anatomy

1. Anatomy Wednesday, November 5, 2014 1

2. Digestive system • MOUTH: Food stuff are broken mechanically by chewing and saliva is added as a lubricant. • Esophagus: A simple conduit between the mouth and stomach. • Stomach: Where the real action begins- enzymatic digestion of proteins initiated and food reduced to liquid form. • Liver: The center of metabolic activity in the body- its major role in the digestive process is to provide bile salts to the small instestine, which are critical for digestion and absorption of fats • Pancreas: Important roles as both and endocrine and exocrine organ- provides a potent mixture of digestive enzymes to the small intestine which are critical for digestion of fats, carbohydrates and protein. • Small Intestine: This is where the final stages of chemical enzymatic digestion occur and where almost all nutrients are absorbed. • Large Intestine: water is a bsorbed, baccterial fermentatation takes place and feces are formed. Digestive sytem links 2

3. RESPIRATORY SYSTEM • Nasal Cavity: Air passing over the mucous membrane of the nasal cavity is moistened, warmed, and filtered. • Pharynx: the pharynx, or throat, is located where passages from the nose and mouth come together. • Epiglottis: The epiglottis is a flap of elastic tissue that forms a lid over the opening to the trachea. • Larynx: The larynx, or voice box, is located between the pharynx and the trachea. • Lungs: if one lobe is injured or diseased, the other lobes may be able to function normally. • Bronchiole: Inside the lungs, the bronchi branch into smaller tubes called the bronchioles. • Alveoli: At the ends of the bronchioles are bunches of alveoli, air sacs, arranged like grapes on a stem. • Trachea: • From the larynx, air enters the trachea, or windpipe, which leads toward the lungs. • Bronchi: The trachea divides into two tubes, bronchi. 3

4. REPRODUCTIVE SYSTEM • The bladder is the muscular sac that stores the urine until it is released trough the urethra. • The urethra is the tube that carriessemen and urine out of the penis. • The two testicles produce sperm and the male hormone testosterone. • Uterus: the organ that houses and nourishes the developing embrio and fetus. The womb. Female reproductive organ in which the fertilized egg implants. • Cervix: the lower neck of the uterus that opens into the vagina. 4

5. LYMPHATIC SYSTEM • What is the lymphatic system? The lymphatic system is a system of thin tubes that runs throughout the body. These tubes are called 'lymph vessels'. You may also hear them called 'lymphatic vessels'. The lymphatic system is like the blood circulation - the tubes branch through all parts of the body like the arteries and veins that carry blood. Except that the lymphatic system carries a colorless liquid called 'lymph'. ﾊ Lymph is a clear fluid that circulates around the body tissues. It contains a high number of lymphocytes (white cells). Plasma leaks out of the capillaries to surround and bathe the body tissues. This then drains into the lymph vessels. 5

6. Nervous System • The Nervous System is the most complex and delicate of all the body systems. At the centre of the nervous system is the brain. The brain sends and receives messages through a network of nerves. This network can be explained as similar to a road network. The spinal cord is a thick bundle of nerves which runs down the centre of the spine. This is like a freeway. Along the spinal cord smaller bunches of nerves branch out. These are like highways. From these bundles, smaller bundles of nerves branch out again. These are like main roads. Finally, individual nerves branch out to every part of the body. These are like normal roads. 6

7. Skeletal System • Its 206 bones form a rigid framework to which the softer tissues and organs of the body are attached.Vital organs are protected by the skeletal system. The brain is protected by the surrounding skull as the heart and lungs are encased by the sternum and rib cage.Bodily movement is carried out by the interaction of the muscular and skeletal systems. For this reason, they are often grouped together as the musculo-skeletal system. Muscles are connected to bones by tendons. Bones are connected to each other by ligaments. Where bones meet one another is typically called a joint. Muscles which cause movement of a joint are connected to two different bones and contract to pull them together. An example would be the contraction of the biceps and a relaxation of the triceps. This produces a bend at the elbow. The contraction of the triceps and relaxation of the biceps produces the effect of straightening the arm.Blood cells are produced by the marrow located in some bones. An average of 2.6 million red blood cells are produced each second by the bone marrow to replace those worn out and destroyed by the liver.Bones serve as a storage area for minerals such as calcium and phosphorus. When an excess is present in the blood, buildup will occur within the bones. When the supply of these minerals within the blood is low, it will be withdrawn from the bones to replenish the supply.Divisions of the Skeleton 7

8. Muscular System • Science Fact file･ Muscles are bundles of cells and fibers. Muscles work in a very simple way. All they do is tighten up--that is, contract--and relax. You have two sets of muscles attached to many of your bones which allow them to move. There are 630 active muscles in your body and they act in groups.Muscles can only pull. They never push. 8