Transcript Powerpoint
The Transportation of our Body • The cardiovascular system, also called the circular system, consists of the heart, blood vessels, and blood. • It is responsible for achieving 3 main goals: Delivering Needed Materials, Removing Waste Products, and Fighting Disease. • The cardiovascular system also picks up waste from cells. It exhales all unwanted cell wastes. • Coronary Artery disease is when your arteries become narrow causing for less blood flow. • Fatty substances then clog up those arteries, therefore not delivering enough blood to the heart, which would cause a heart attack. • Heart attacks are potentially fatal. The Heart • The heart is a hollow, muscular organ that pumps blood throughout the body. • The Heart is divided into 2 parted by the septum. • The Heart works in 2 phases. • In one phase, the heart muscle relaxes and the heart fills with blood. • In the second phase, the heart muscle contracts and pumps blood forward. The Arteries • When blood leaves the heart, it travels through the arteries. • The walls of the arteries are very thick, they are made up of three parts, the innermost layer, the middle layer, and the outer wall. • If you touch the inside of your wrist, you can feel your pulse. • Your pulse is caused by the alternating expansion and relaxation of the artery wall. The Capillaries • In the capillaries, materials are exchanged between the blood and the body’s cells. • Capillary walls are only one cell thick. • One way that materials are exchanged between the blood and body cells is by diffusion. • Diffusion is the process by which molecules move from an area of higher concentration to an area of low concentration. The Veins • After blood moves through capillaries, it enters larger blood vessels called veins. • The walls of veins, like the arteries, are made up of three layers. • The purpose of the many veins in the body are to carry blood back to the heart. Our “Way of Life” • Your body cells need oxygen to survive. • Your body cells receive oxygen from the air you breathe. • The Respiratory System moves oxygen from the outside environment into the body. • It also removes carbon dioxide and water from the body. Taking in Oxygen • The oxygen your body needs comes from the atmosphere. • Oxygen is needed for the energy-releasing chemical reactions that take place inside your cells. • Asthma is a Respiratory disease in which a person’s airways get swollen and narrower therefore making it hard to breathe. The Path of Air • Air enters the body through the nose and moves into space called the nasal cavities. • It then goes through the pharynx, or the throat. • From there, air goes through the trachea. • After that, air moves into the bronchi, which lead directly to the lungs. • The lungs are the main organs of the respiratory system. Gas Exchange • Because the walls of both the alveoli and the capillaries are very thin, certain materials can pass through them easily. • After air enters an alveolus, oxygen passes through the wall of the alveolus and then through the capillary wall into the blood. • Carbon dioxide and water pass from the blood into the alveoli. • This whole process is known as gas exchange. How You Breathe • Every day, you breathe an average of 20,000 times. • Breathing is controlled by muscles. • When you breathe, the actions of your rib muscles and diaphragm expand or contract your chest. • As a result, air flows in or out. Feeling Down? • The nervous system receives information about what is happening both inside and outside your body. • It also directs the way in which your body responds to this information. Functions of the Nervous System • Because of your nervous system, you are aware of what is happening in the environment around you. • Any change or signal in the environment that can make an organism react is called a stimulus. After your nervous system analyzes the stimulus, it causes a response. • The nervous system helps maintain homeostasis by directing the body to respond appropriately to the information it receives. The Neuron • Your nervous system includes various organs, tissues, and cells. • The cells that carry information through your nervous system are called neurons, or nerve cells. • Three kinds of neurons are found in the body: sensory neurons, interneurons, and motor neurons. Nerve Impulses • Every day of your life, billions of nerve impulses travel through your nervous system. • The junction where one neuron can transfer an impulse to another structure is called a synapse. • For a nerve impulse to be carried along at a synapse, it must cross the gap between the axon and the next structure. • The axon tips release chemicals that carry the impulse across the gap. Alzheimer’s Disease • Alzheimer's is the most common form of dementia that causes problems with memory, thinking and behavior. • Symptoms usually develop slowly and get worse over time, becoming severe enough to interfere with daily tasks. • The majority of people with Alzheimer's are 65 and older.