CIRCULATORY B

Blood vessels and the blood

3 TYPES OF BLOOD VESSELS

1. Arteries - brings blood from the heart to the organs

2. Capillaries –very fine tubes that branches into a network

3. Veins – brings blood back to the heart

STRUCTURE OF BLOOD VESSELS

1. Epithelial cells - single innermost layer

2. Smooth muscles - middle layer arranged in a circular manner. Big Arteries also have elastic fibers among smooth muscles.

3. Connective tissues - outmost layer with some elastic fibers and nerve cells.

BLOOD PRESSURE

Blood pressure is the pressure of blood against the walls of the main arteries

The pressure is the highest when the ventricles of the heart contract

Blood pressure is measured at an artery in the arm where the pressure is most similar to that of blood leaving the heart.

COMPOSITION OF BLOOD

a) The liquid portion of blood is only slightly greater by volume than the solid portion.

b) The red blood cells are greater in number than white blood cells.

c) The liquid portion of the blood is mostly water

COMPOSITION OF BLOOD

d) Blood proteins are normal components of blood plasma.

e) Substances that blood transports include both organic and inorganic materials.

f) The blood cells are 45% of the whole blood while the Blood Plasma is 55% of the whole blood

RED BLOOD CELLS

a) Their red colors come from the pigment hemoglobin

b) Hemoglobin in red blood cells make them best adapted for transporting oxygen to the body cells.

c) Red Blood Cells are only about 7-8 microns in diameter.

d) They are produced in the red marrow of flat bones.

RED BLOOD CELLS

d) Young red blood cells have nuclei, but they lose it when they mature

e) They only live for only about 120 days

f) They stay on the bloodstream for about 10-30 days

g) Worn out red blood cells are broken down mostly in the liver and spleen.

WHITE BLOOD CELLS

Leukocytes Larger than red blood

cells It protects or defends

the body from infectious diseases to move through the body

BLOOD PLATELETS

Thrombocytes irregularly shaped cell fragments involved in hemostasis, blood clots. 2-3 micrometers in diameter If platelets too low, excessive

bleeding may occur. If platelets are too high, blood clots

can occur.

COMMON DISEASES

Leukemia Affects blood-forming cells in

the body. Characterized by an abundance of abnormal white blood cells in the body.

The bone marrow starts to make a lot of abnormal white blood cells and they don't do the work of normal white blood cells.

Anemia A condition in which the body

does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues.

Symptoms Feeling grumpy Feeling weak or tired more

often than usual, or with exercise

Headaches Problems concentrating or

thinking

SOURCES