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Body Systems Essay Research Paper Body SystemsKnowing

Body Systems Essay, Research Paper

Body Systems

Knowing about the body systems is important. When you know about your body, you?ll be more healthy than if you didn?t. Any sport player needs to know and understand how all his muscles work, so when it comes to exercise or working out, they can know what their limits are.

The skeletal system is made up of your bones, ligaments, and tendons. It determines the shape and symmetry of the body; acts as a protective device for your organs; acts as a firm base for the attachments of muscles (without bones, your muscles would not function properly); and the marrow tissues in the cavity of the bones produces red cells and some white cells, required in your blood.

Humans have an endoskeleton, meaning that the skeleton is located inside of the body. It consists of about 200 bones. The number of bones varies, because some bones fuse at different periods of time. Most bones are hollow with marrow bones inside. Ligaments connect bones to bones, and tendons connect bones to muscles.

The human skeleton is divided into an appendicular skeleton (bones of arms and legs or “appendages”), and the axial skeleton (skull, backbone or “vertebrae”)

The human body contains more than 650 individual muscles which are attached to the skeleton, which provides the pulling power for us to move around. The main job of the muscular system is to provide movement for the body. The muscular system consists of three different types of muscle tissues: skeletal, cardiac, and smooth muscles. Each of these different tissues has the ability to contract, which then allows body movements and functions. There are two types of muscles in the system and they are the voluntary and involuntary muscles. The muscles that we are allowed to control ourselves are called the voluntary muscles. The muscles we can?t control are called the involuntary muscles. The heart, or the cardiac muscle, is an example of involuntary muscles.

The human nervous system is responsible for sending, receiving, and processing nerve impulses throughout the body. All the organs and muscles inside your body rely upon these nerve impulses to function. It could be considered as the master control unit inside of your body. Sense organs provide the nervous system with information about the environment by means of such senses as sight, hearing, smell, taste, touch, pressure, and pain. Nerves are connected throughout the whole body to the brain. They carry the information throughout the body in the form of electrochemical signals called impulses. These impulses travel from the brain and spinal cord to the nerves located throughout the body. It is largely made up of specialized cells called neurons. Each of these neurons has a cell body, or cyton, which contains the nucleus and organelles. It takes the corporation of three systems to carry out the mission of the nervous system. They are the central, the peripheral, and the autonomic nervous systems.

The endocrine system is a collection of special organs in the body that produce hormones. Theses organs are usually called the “glands.” They are located in different parts of the body. For example, the pituitary is in the brain, the thyroid is in the neck, the adrenal glands are in the kidneys, and the sexual glands (ovaries and testes) are located in the sexual organs. Each gland releases a hormone into the blood, which travels all through the body. Hormones regulate our body activities, for example: growth, sleep, sudden actions, feelings and blood sugar for energy.

The digestive system contains organs for changing food chemically for absorption by body tissues. It is also responsible for processing food, breaking it down into usable proteins, minerals, carbohydrates, fats, and other substances. The digestion process involves breaking food into simple soluble substances absorbable by tissues.

The digestion process includes both mechanical and chemical processes. The mechanical processes include chewing to reduce food into smaller particles, the churning actions of the stomach, and the intestinal peristaltic action. Three different chemical reactions take place: conversions of carbohydrates into such simple sugars as glucose, breaking down of protein into amino acids, and the conversion of fats into fatty acids and glycerol. These processes are accomplished by specific enzymes.

The respiratory system?s main task is to supply oxygen to the blood and to get rid of waste gases. Carbon dioxide is the primary gas that the blood needs to get rid of. The upper structures of the respiratory system are combined with the sensory organs of smell and taste and the digestive system. When you inhale (breathing in) your skeletal; muscle and the diaphragm contract, which then enlarges the chest cavity and causes the lungs to draw in air. This creates a partial vacuum in the thoracic cavity, air passes through the nose, pharynx, larynx, trachea, and then into the two bronchi to the lungs. Oxygen and carbon dioxide passes between the blood and the air in the alveoli, which are at the ends of the smallest bronchi. Oxygen diffuses from the inhaled air through the alveoli walls into the capillaries. The lungs contain more than 300 million alveoli. When you exhale or breathe out, your skeletal muscles and diaphragm returned to the relaxed position which decreases the size of the chest cavity and therefore pushes air out of the lungs. The rib cage serves as a structural support for the whole thoracic arrangement, and peural membranes help provide lubrication for the respiratory organs so that they are not chaffed during respiration. The air we exhale contains 100 times more carbon dioxide than inhaled air. In a resting position, a healthy individual will inhale and exhale approximately 16 times per minute.

The circulatory system is composed of vessels and muscles that control the flow of blood around the body. This process of blood flowing around the body is called circulation. The main components of the circulatory system are the heart, arteries, capillaries, and the veins. Let?s take a look at how blood travels around your body. Firstly, the blood leaves the heart from the left ventricle into the biggest artery, called the aorta. The heart is a strong muscle, which is divided into 4 compartments (the left and the right ventricles). It is important that fresh blood from the aorta goes directly to the brain, because the brain needs oxygen constantly, otherwise, you could get irreversible damage. Another important organ for blood to pass through is the blood. Here waste carbon dioxide is replaced with fresh oxygen. The pressure in the arteries is higher than in the veins. Blood returns to the heart through the veins.

The excretory system is responsible for the removal of waste substances from the body. Several organs are involved with the excretory system, including the kidneys, sweat glands, lungs and rectum. The primary organs of excretions, however, are the kidneys. Excretion is vital to the health of the body because the wastes are poisonous. If the wastes build up and are not eliminated, they can cause serious problems. As you know, carbon dioxide and water vapor are removed by the lungs. Other wastes, namely urea, uric acid, various salts, and assorted nitrogenous wastes are removed by the kidneys and sweat glands.

The chief mission of the reproductive system is to further the evolution of the human race. Sexual reproduction involves 2 parts: the egg, which is provided by the female, and sperm, which is provided by the male. They fuse to form the fertilized egg, which grows into an offspring.

In the male, the primary sexual organs are the testes and the penis. The testes, which produce sperm, are located in the scrotal sac. It consists of approximately 1000 highly coiled seminiferous tubes with a total length of 250 meters. Vas efferntia, the fine tubes, connect the semineferous tubes to the urethra, a tube connecting the urinary bladder to the exterior that goes through the penis. Erectile tissue, also located in the penis, causes erection during periods of sexual excitement.

The primary sexual organs for the female are the ovaries, the clitoris, and the Labia minora and the Labia majora. The eggs are produced by the ovaries, which is about 3 cm long, and they are passed into the uterus, through one of the two fallopian tubes. The uterus, which is about the size of a clenched fist, is where the embryo develops. It is covered with thick walls of smooth muscles, and mucous lining. The vagina serves as a birth canal, and a receptacle for sperm. The vulva, the external female organs include; labia majora, labia minora, and the clitoris. Labia minora and labia majora enclose the opening of the urethra and vagina. The clitoris is a sensitive erectile organ, which responds to erotic stimulation.

Bibliography

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