cardiovascular and respiratory systems ch. 16

Cardiovascular and Respiratory Systems

Chapter 16

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)

The Heart

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


� Heart Murmur

� Abnormal sounds that are made as blood flows through the heart

� May indicate a valve not closing properly and may require surgery


� 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

Varicose Vein

� 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



� 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


� 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

Structure of the Respiratory System

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

Other Respiratory Structures cont.

� Larynx- voice box

� Contains vocal chords- two bands of tissue that produce sound when air forced between them causes them to vibrate

� Epiglottis- flap of cartilage that closes off the entrance of the larynx and trachea when you swallow

cardiovascular and respiratory systems ch. 16

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