UNIT 3: Blood

Question 1

plasma

Answer 1

the liquid portion composed mostly of water.
it makes up approx. 54% of blood volume.
it functions in transporting cells and substances all around the body.

Question 2

red blood cells

Answer 2

also called erythrocytes.
made in the bone marrow of long bones.
they function in transporting oxygen around the body.
have a red pigment called hemoglobin that enables them to carry out this role.
haemoglobin is a protein with an iron atom in its centre.
red blood cells have a biconcave shape, this enables them to transfer oxygen more efficiently as it has a greater surface area for diffusion.
red blood cells do not have a nucleus, this enables them to carry more haemoglobin and hence oxygen and enables them to be smaller cells capable of squeezing through very narrow capillaries.

Question 3

white blood cells

Answer 3

produced in the bone marrow and mature in various organs and tissues throughout the body.
they function in keeping the body free of pathogens (disease causing protists, bacteria and viruses).
1. monocytes - develop into more specific white blood cells called macrophages and phagocytes.
2. lymphocytes - develop into a variety of sub-types of lymphocytes, some of which are responsible for producing antibodies.

Question 4

plateles

Answer 4

known as thrombocytes.
produced in the bone marrow and function in blood clotting.
deep vein thrombosis can result if blood clots form in a vein - usually in a large vein in the leg

Question 5

blood groups

Answer 5

ABO blood group system is the most important blood grouping system.
- A
-B
- AB
- o
another blood grouping system is the Rhesus system.
everyone is either rhesus positive (Rh+) or rhesus negative (Rh-).
if rhesus positive, they possess the rhesus factor on the surface of their red blood cells. if negative, they do not

Question 6

Serum

Answer 6

Plasma from which the clotting proteins have been removed