BLOODWHAT IS IT?

BLOOD Consists of two distinct elements:

Plasma: fluid portion (55%) Water Dissolved gases: _____________________ Proteins Sugars Vitamins Minerals waste

Formed: composed of cells (45%) Mostly red and white blood cells.

Red Blood Cells Also called ERYTHROCYTES Make of 44% of the 45% “formed” part of

blood. Specialized for ____________ transport.

Mature cell has no nucleus Packed with respiratory pigment called

HEMOGLOBIN: iron-containing molecule that binds with oxygen.

Blood Colour is Determined by Different Respiratory Pigments You may have noticed the different

colours of fluid produced by ‘squished’ organisms... this is partially the reason:

White Blood Cells Also called LEUCOCYTES. Make up only about 1% of blood volume. Play a major role in helping body fight off

pathogens. HAVE NUCLEI!

CENTRIFUGATION of a blood sample.

Platelets Not cells. Fragments of cells from bone marrow. Important role in clotting blood protection from

excessive blood loss after injury. Steps to blood clotting (still not completely understood):

Blood vessel broken substances released by broken blood vessels attract platelets platelets rupture and chemicals released thromboplastin (enzyme) is produced reacts with prothrombin to produce thrombin reacts with fibrinogen fibrin.

Fibrin: insoluble material that forms a mesh of strands around an area of injury. Traps escaping blood cells!

Blood Plasma Medium in which blood cells/platelets are

suspended Contains dissolved proteins which are

important to all blood functions: Red blood cell processes White blood cell processes Platelet processes,

Etc.

Classwork/Homework Read “Human Blood Groups” (page 300)

and make detailed notes.

Complete the following SR questions (page 303) #1, 2, 4, 8, 9, 11.