The circulatory system transports materials to and from all the parts of an organism.

Transport – The life process by which materials move into or out of or are distributed within cells.

A. Transport in Humans- transport system made up of tissues and organs.

    1. Functions of the Transport system:

        a. Transport of nutrients and other materials.

        b. Immunity – fighting off/ protection against infections

        c. Regulation – control to maintain homeostasis ex body temp, clotting of blood

    2. Transport medium is Blood and Lymph  (about 5 liters of blood)

        a. Blood- liquid tissue

            1. Plasma- liquid portion of the blood, mostly water 90% with some ions, nutrients, wastes, vitamins and minerals. 55% of total volume

            2. Red Blood Cells function is to transport oxygen to the cells and take away CO2 from the Cells.

            About 30 trillion RBCs

            Contain hemoglobin (protein which contains iron, binds with O2 gives blood it’s red color)

            RBCs are produced in bone marrow and lose their nucleus Live only 120 days then are removed by liver and spleen            Disk shaped

            3. White blood Cells Colorless cells that protect the from infections by viruses and bacteria.

            60 billion

            Have nucleus so can replicate

            Made by bone marrow

        -2 types (phagocytes and lymphocytes)

Phagocytes- protect the body from viruses and bacteria by engulfing them through phagocytosis.

Lymphocytes- Produce substances called antibodies react to antigens rendering them harmless.

Antigen - protein on cell that can identify it

Antibody– protein in blood that can bind to and destroy foreign substances.

Platelets – smallest of all three (cell fragments) no nucleus, involved in the production of fibrin which aids in blood clotting

b. Intercellular Fluid (ICF) and Lymph

ICF is plasma (water and dissolved material) that are forced out of the blood by blood pressure at the capillaries (small blood vessels connect veins to arteries)

- Carries O2 and nutrients to the cells of tissue and takes CO2 and wastes back into the capillaries.

- Some enters another transport system called Lymphatic System

Lymphatic System —where it is called Lymph – includes lymph nodes which trap foreign materials -

1. Major function of the lymphatic system

a. Maintain volume of blood by collecting ICF and returning it to blood stream.

b. Lactiels in Small intestine pick up fat and add it to blood stream

c. Part of immune system- large amounts of white blood cells found here.

B. Disorders of the Blood

1. Anemia Low of functioning RBCs causes fatigue

2. Sickle cell anemia – Hemoglobin is misshaped doesn’t function properly genetically inherited

3. Hemophilia low platelet count problems with blood clotting

4. Leukemia Cancer of the bone marrow produces uncontrolled amounts of nonfunctional WBCs

C Protective functions of Blood- 3 lines of defense

1. Skin and Mucus

2. Phagocytes

3. Immune response.

a. Lymphocytes produce antibodies, which attach themselves to antigens            (viruses or bacteria)

b. Antibodies render antigens (disease causing antigens are called pathogens) harmless (make them inactive)

c. Phagocytes engulf both antigens and antibodies

D. Immunity To Disease -  the ability of the body to resist specific diseases due to the presence of particular antibodies in the blood. Immunity is based on the ability of the body to recognize self and non-self. There are 2 types of immunity

1. Active Immunity acquired by

a. actually having the disease recovering and producing antibodies

b. Vaccination weakened or killed form of disease causing antigen is injected into blood. antibodies against the disease are produced. Preventive measure

2. Passive Immunity - temporary injection of antibodies from another person (mothers milk)

3. Allergies an overreaction to an antigen that is normally harmless

a. Dust, pollen, insect bites, some foods, etc, may illicit immune response in some people.

b. Cause antibody production

c. Symptoms vary depending on the allergen and route of entry. Cause Histamine release

E Blood Types

1. The surface of every human cell has antigens

2. Red blood cells also have antigens ( protiens ) on there surface.

3. Two types of Antigens, A and B:

a. A person who has antigen A is type A Blood

b. A person who has antigen B is type B Blood

e. A person with both is type AB

d. A person with no antigens is type 0

4. Antibodies are also naturally present in the plasma

a. Person with type A has anti B present

b. A person with type B has anti A present.

** If type A was to be mixed with anti A the result would be a clump of red blood cells.

5. Blood type is inherited

6. Blood type is very important when considering blood transfusions

a. Type 0 is considered the universal donor

b. Type AB is considered the universal acceptor

7. Also important in organ transplant -

8. Another protein factor called Rh (+ or - ) is also very important.        

AIDS — (Acquired Immune Deficiency Syndrome)

1. Disease caused by the HIV virus .

2. Virus attacks certain types of Lymphocytes (white blood cells).

3. Weakened immune system is no longer able to fight off infection. Usually die of a secondary infection.

4. Aids is spread by:

a. Sexual contact -  exchange of fluids

b. Sharing Needles

c. Blood transfusions

G. Human circulatory system — we have a Closed circulatory system. (blood is transported to tissues in blood vessels)

1. Types of Vessels

a. Arteries carry blood away from the heart, thick and muscular, elastic, no valves except at heart

b. Veins carry blood to heart, thin walled not elastic, valves present, no nerve endings

c. Capillaries- one cell layer thick, connect small arteries (arterioles) to small veins (venules)

d. Blood Pressure - pressure exerted by the blood against the walls of the arteries

1. Systolic is the pressure during contraction of the left ventricle.

2. Diastolic is the pressure during the relaxation of the left ventricle.

3. The blood pressure for a young normal adult is 120/80 (systolic / diastolic).

e. Pulse is C is the expansion and relaxation that can be felt in an artery each time the left ventricle contracts and relaxes.

The frequency of the pulse rate is tile same as the heart beat.

 

2. The Heart

- consists of 4 chambers, made up mostly of cardiac muscle

- Partition called the septum separates the left side and right side of the heart

- thin walled atrium on each side receive blood.

- contraction of atria forces blood through into the thick walled receiving chamber called ventricle

- contraction of ventricles forces blood into a large artery that carries blood away from the heart.

- valves found in the heart prevent the backflow of blood.

3. Path of Circulation:

a. 4 chambered heart of birds and mammals permits complete separation of oxygenated blood from deoxygenated blood.

b. the right side of the heart sends deoxygenated blood to the lungs for oxygen.

c. the left side of the heart sends oxygenated blood to the rest of the body.

d. the left ventricle has the thickest wall because it pumps blood to all parts of the body except the lungs

4. Pulmonary circulation

a. involves pathway of blood between lungs and heart.

b. deoxygenated blood leaves right ventricle divides into two pulmonary arteries that carry blood to the lungs

c. arteries divide to form capillaries.

d. blood picks up oxygen in the lungs and turns bright red in color.

e. blood leaves the lungs and enters pulmonary veins.

f. blood then enters the left atrium of the heart.

5. Systemic Circulation

a. circulation through the major systems of the body

b. left atrium forces oxygenated blood into the left ventricle

c. left ventricle contracts- blood leaves the heart through the largest artery called the aorta

d. Arteries divide to smaller arteries and eventually arterioles

e. Arterioles are divided even further into capillaries where exchange of material occurs between blood and tissue cell.

f. Capillaries then unite to form venules, which unite to form veins.

Arteries, Arterioles, Capillaries, venules, veins

g. The superior vena cava receives blood from the head region and the inferior vena cava  receives blood from the trunk region. The blood is then emptied into the right atrium.

6. Coronary circulation

a. Blood is supplied to the heart by the coronary vein

b. Blood is returned to the heart by the coronary artery

7. Hepatic - Portal Circulation

a. Capillaries in the stomach, small intestine, and large intestine do not lead back to the heart.

b. They lead to veins which go to the liver

c. Aids in regulation of blood glucose levels

d. renal circulation carries blood to and from the kidneys

8. Malfunctions of the Transport System

a. High blood pressure

- also called hypertension, a condition where blood pressure is always above normal

- may be result from:

1. Kidney problems

2. Narrowing of the coronary arteries

3. Arteriosclerosis hardening of the arteries

4. Stress

5. Excess sodium in diet

6. Heredity. Aging, smoking

b. Heart Attacks (two types)  

1. Coronary thrombosis — blockage of coronary artery caused by a blood clot — causes part of the heart muscle to die.

2. Angina pectoris — caused by a blockage of coronary arteries — causes part of the heart muscle to die.

H. Transport in Protists

1. One celled so have no need for a complex transport (circulatory) system.

2. diffusion and active transport - are enough to move materials in and out.

3. With in the cell movement is aided by cyclosis (streaming of cytoplasm)