Post on 03-Feb-2022
Functions of the Cardiovascular System
� Circulate blood so that all of the body’s cells are properly nourished and waste is carried away
� Blood brings oxygen and nutrients
� Blood takes away Carbon Dioxide (lungs) and waste products (kidneys)
Chambers of the heart
� Atrium: two smaller (upper) chambers
� Ventricles: two bigger (lower) chambers
� Septum: separates right and left atria and ventricles
� Upper right atrium also acts as the natural pacemaker. Electrical impulses to the heart start here.
Make-up of Blood
� Plasma: fluid in which other parts of the blood are suspended (55%)
� Mostly water, contains nutrients, proteins, salts and hormones
� Red Blood cells (40%)
� White Blood cells (5%)
Red Blood Cells
� Transport oxygen to the cells and tissues of the body
� Formed in bone marrow
� Hemoglobin: oxygen carrying protein in blood
� Also combines with CO2
White Blood Cells
� Protect the body from infection and fight infection when it occurs
� Formed in bone marrow
� Production increases when an infection is present
� Some wbc’s eat the disease
� Some cause an allergic reaction
� Others form antibodies that provide immunity
Blood Vessels
� Arteries-carry blood away from the heart
� Veins-return blood to the heart
� Capillaries-small vessels that carry blood between arterioles and venules
� Platelets- cells that prevent the body’s loss of blood
The Lymphatic System
� Lymph- clear fluid that fills the spaces around body cells
� Contains water, proteins, fats and lymphocytes
� Lymphocytes- specialized white blood cells that provide the body with immunity
� Two types: B cells and T cells
B Cells
� Multiply when they come in contact with a pathogen
� Some B cells attack the patogen
� Other B cells form memory cells that are activated if the body is exposed to the same pathogen a second time causing immunity
T Cells
� Enlarge and multiply when they encounter a pathogen
� Killer T’s: release toxins that destroy abnormal and infected cells
� Helper T’s: aid in activation of B cells and killer T cells and control the body’s immune system
Structure of Lymphatic System
� Series of vessels and tissues that move and filter lymph
� Lymph is moved towards the heart and circulated through out the body
� Lymph Node: (bean shaped organs) wbc’s trap and destroy foreign organisms and keep them from spreading through out the body.
� Spleen, thymus gland and tonsils
Health Behaviors and the Cardiovascular and Lymphatic Systems
� Follow a well-balanced diet low in saturated fats, cholesterol and salt
� Maintain a healthy weight to reduce stress on the heart, blood vessels and lymph vessels
� Participate in regular aerobic exercise for at least 30 minutes three to four times per week
� Avoid the use of tobacco products and exposure to secondhand smoke
� Avoid illegal drugs
Blood Pressure
� Measure of the amount of force that the blood places on the walls of blood vessels, particularly large arteries and it is pumped through the body
� Measured by a sphygmomanometer and stethoscope
� Systolic pressure: maximum pressure on the arteries
� Diastolic pressure: ventricles relax to refill. Blood pressure is at it’s lowest point
� 120/80 is considered normal blood pressure
� 140/90 is considered high and places a strain on the heart as it pumps
Cardiovascular System Problems
� Heart Defects
� Congenital: condition that is present at birth
� Septal Defect: hole between the right and left side of the heart
� Valves may not function properly or aorta may be too narrow
Cardiovascular System Problems cont.
� Cardiovascular Disease (CVD)
� Group of diseases that include hypertension, heart disease and stroke
� Number 1 killer of both men and women in the U.S.
� 95,000 Americans die every year
Cardiovascular System Problems cont.
� Heart Murmur
� Abnormal sounds that are made as blood flows through the heart
� May indicate a valve not closing properly and may require surgery
Cardiovascular System Problems cont.
� Varicose Veins
� Valves inside the veins do not close tightly enough to prevent backflow of blood
� Can be result of congenital defect or aging process
� Physical activity helps prevent V.V.
� Surgery may be required
� Anemia
� Condition in which the ability of the blood to carry oxygen is reduced
� Can result from low rbc count or low concentrations of hemoglobin in the blood
� Iron deficiency is similar
� Eat green leafy vegetables, red meat, liver, egg yolks and fortified cereals
Cardiovascular System Problems cont.
Cardiovascular System Problems cont.
� Leukemia
� Form of cancer in which any one of the different types of wbc’s is produced excessively and abnormally.
� Abnormal cells cannot function properly and the patient is susceptible to infection
� Often hinder production of rbc’s and platelets in the bone marrow
� Can be treated with bone marrow transplants
Cardiovascular System Problems cont.
� Hemophilia
� Disorder in which the blood does not clot properly
� Proteins called clotting factors are absent
� May cause uncontrolled bleeding that may occur spontaneously or internally
� Treatment includes injections that introduce clotting factors
Lymphatic System Problems
� Immune Deficiency
� Immune system can no longer protect itself from infection
� Some may be congenital, others can be casued by HIV.
� Can also be a result of natural aging or a side effect to chemotherepy
Lymphatic System Problems cont.
� Hodgkin’s Disease
� Type of cancer that affects the lymph tissue found in lymph nodes and spleen
� Early detection and treatment is essential for recovery
� Treatment may include removal of lymph nodes, radiation and chemotherapy
Lymphatic System Problems cont.
� Tonsillitis
� Part of immune system
� Common in children
� Can be treated with antibiotics or surgical removal of the tonsils
Functions of the Respiratory System
� Respiration- the exchange of gasses between the body and the environment
� Two parts of respiration
� External- exchange of O2 and CO2 in the blood in the lungs
� Internal- exchange of gasses between blood and body cells
The Lungs
� Air moves into the lungs through the trachea.
� Trachea branches into the bronchi
� The bronchi subdivide to tubes called bronchioles
� At the end of the bronchioles are microscopic structures called alveoli
� Thin-walled air sacs covered with capillaries. Gas exchange takes place here.
Lungs cont.
� Diaphragm- the muscle that separates the chest from the abdominal cavity
� Breathing is made possible by differences in pressure inside and outside your lungs
� Air flows to areas of low pressure
� Hiccups occur as a result of your diaphragm contracting in a spasm, quickly followed by the closure of the vocal chords
Other Respiratory Structures
� Nose- lines with hair-like structures called cilia
� Cilia along with mucous trap and remove foreign particles (dust, bacteria and viruses)
� Air is warmed and moistened and sent down the pharynx (throat) and into the trachea (windpipe)
� Both are also lined with cilia and mucus