Ch. 23 Circulation & Respiration

Section 1: The Cardiovascular System Objectives: List four main parts of the cardiovascular system, and describe their functions. Describe the two types of circulation of blood in the body. List four cardiovascular problems.

Cardiovascular system components: Heart Arteries Capillaries Veins

Heart 4 Chambers: right atria left atria right ventricle left ventricle valves-separate chambers aorta – major artery vena cava – major vein pulmonary artery and vein

3 Types of Blood Vessels: Artery Capillary Vein

Arteries Arteries Always carry blood Away from the heart Thick walls to support pressure from heart pumping Usually bright red due to highly oxygenated blood Aorta – major artery supplying body’s blood Coronary artery – supplies heart’s blood Carotid artery – supplies brain’s blood Pulmonary artery – supplies lung’s blood (low O2 – darker)

Capillaries Smallest of all blood vessels – single file Where the diffusion of gases and other molecules takes place (things entering and leaving your blood) No cell in your body is more than 3 or 4 cells away from a capillary

Veins Always take blood towards the heart Thinner than arteries Darker color due to less oxygenated blood Vena Cava – major vein returning body’s blood Jugular vein – vein returning brain’s blood Pulmonary vein – returning lung’s blood (high O2 – bright)

2 Types of Circulation (Blood Flow) Pulmonary Circulation – heart to lungs and back Systemic Circulation – heart to rest of body and back

Cardiovascular Problems Atherosclerosis When cholesterol builds up in the walls of blood vessels and restricts blood flow High Blood Pressure (Hypertension) Stroke – when a blood vessel in the brain becomes clogged or ruptures  part of the brain receives no oxygen  brain cells die.

Cardiovascular Problems Heart Attack / Heart Failure Heart attack - when heart muscle cells die and part of the heart is damaged. Too many cells dying could cause the heart to stop. (cardiac arrest) Heart failure – not enough blood being pumped to the body. Important organs may suffer or stop working.

Section 2: Blood Objectives: Identify the four main components of blood. Describe three functions of blood. Explain how blood pressure is measured. Explain what the ABO blood types are and why they are important.

Blood 3 Functions: Transport  sends nutrients and oxygen throughout your body Immunity  protects your body against antigens Healing  clots to stop bleeding after a cut or bruise 55% Plasma – mostly water 44% RBC 1% WBC and platelets

Plasma Liquid Mostly water Functions: Transport Carries hormones and wastes Makes up 55% of the blood

Red Blood Cells (erythrocytes) Most numerous Formed in the bone marrow Functions: Carries oxygen and nutrients to body and waste back Filled with the protein hemoglobin, which contains iron (makes your blood red, like rust)

Platelets Small pieces of cells from bone marrow Functions: Healing Collect around cuts and produce fibrin to make a net to stop bleeding

White Blood Cells (leukocytes) Larger than RBC’s Immunity Functions: Fight off invading organisms (pathogens) Release antibodies to help identify pathogens Destroy damaged/infected cells

Body Temperature Regulation The brain signals blood vessels in your skin to enlarge  excess heat is transferred from your blood to your skin  body temperature decreases Blood Pressure Every time your heart beats, it pushes blood out of the heart and into your arteries. The force exerted by blood on the inside walls of arteries is called blood pressure.

Blood Types Every person has one of four blood types: A, B, AB, or O. Your blood type refers to the type of antigens you have on the surface of your RBCs. Antigens – the markers that identify what kind of blood you have. Antibodies – the markers that look for foreign blood types to attack.

Transfusion – replacing your blood with someone else’s due to blood loss during surgery or an injury. Blood Type Can receive Can donate to A A, O A, AB B B, O B, AB AB all AB only O

Section 3: The Lymphatic System Objectives: Describe the relationship between the lymphatic system and the circulatory system. Identify six parts of the lymphatic system, and describe their functions.

Lymphatic System Like another circulatory system Group of tissues and organs that collects excess fluid and returns it to your blood Helps fight pathogens

Lymph capillaries – absorb fluid and small particles (dead cells/pathogens) near cells Lymphatic vessels carry this lymph back towards your neck where it drains into veins of the cardiovascular system

Other Parts of the Lymphatic System Bone Marrow – where most red and white blood cells are produced Lymph nodes – small bean shaped masses of tissue that remove pathogens and dead cells from the lymph Lymphocytes are types of WBC’s that fill lymph nodes and attack pathogens Lymph nodes get swollen when you have an infection. Why???

Thymus – gland that makes T cells ready to fight Spleen – soft and spongy organ that produces lymphocytes recycles old/damaged RBC’s Tonsils – tissue that stores WBC’s and fights infections

Section 4: The Respiratory System Objectives: Describe the parts of respiratory system and their functions. Explain how breathing happens. Discuss the relationship between the respiratory system and the cardiovascular system. Identify two respiratory disorders.

Respiration vs. Breathing Breathing and respiration are not the same thing. Breathing is only one part of respiration. Respiration = breathing + cellular respiration Breathing - inhaling and exhaling Cellular respiration involves chemical reactions that release energy from food.

The Respiratory System Consists of the group of organs that take in oxygen and get rid of carbon dioxide: Nose Throat (pharynx) Lungs Passageways that lead to the lungs Nose  pharynx  larynx  trachea  bronchi  bronchioles  alveoli  lungs

vocal cords pharynx (throat) trachea (windpipe) larynx lung bronchus bronchiole diaphragm alveoli

Gas Exchange

Breathing diaphragm

Respiratory Disorders Asthma-causes the bronchioles to narrow; causes difficulty breathing; an asthma attack may be set off by irritants like dust or pollen Severe acute respiratory syndrome (SARS) – caused by a virus; may cause fever and difficulty breathing Emphysema-caused by damaged alveoli