Human Biology (Circulatory System and Blood Transfusions)

Question 1

What are the functions of blood?

Answer 1

• Transport oxygen, nutrients and hormones
• Transport CO2 waste away from cells
• Maintain body temperature by distributing heat
• Maintain ph levels
• Clotting of damaged blood vessels
• Immunity against disease

Question 2

Blood moves from the lungs to the ____ and from the heart to the _____ (vice-versa)

Answer 2

1. Heart
2. Body Cells

Question 3

What is the composition of blood?

Answer 3

55% plasma and non-liquid components called formed elements
Erythrocytes(Red Blood Cells)
Thrombocytes (Platelets)
Leucocytes (White Blood Cells)

Question 4

Average amount of blood for adult female and male

Answer 4

Female: 4 - 5L
Male: 5 - 6L

Question 5

What is Plasma made of?

Answer 5

91% water
9% dissolved organic/inorganic substances

Question 6

What are Erythrocytes?

Answer 6

Red blood cells are biconcave discs that have no nucleus. They have an extra surface area which allows them to carry more haemoglobin.

Question 7

What is haemoglobin?

Answer 7

A molecule specifically designed to hold oxygen and carry it to cells.

Question 8

What is a leucocyte?

Answer 8

White blood cells fight disease by making antibodies to destroy invading micro-organisms, be ‘eating’ them through phagocytosis. They are produced by the bone marrow and only live a few days.

Question 9

What is a thrombocyte?

Answer 9

Bits of broken cell fragments. They have no nucleus or functioning organelles, they are formed in the red bone marrow and have little to no life span. Involved in clotting that occurs when a blood vessel is damaged.

Question 10

What are the 3 steps to blood clotting?

Answer 10

1. Vasoconstriction
2. Platelet Plug
3. Coagulation

Question 11

What is Vasoconstriciton?

Answer 11

Muscles in the wall of damaged blood vessels constrict to reduce blood flow in damaged vessel, thus reducing blood loss.

Question 12

What is a Platelet Plug?

Answer 12

Platelets then stick to the rough damaged wall of the blood vessel. Platelets release chemicals that attract even more platelets and cause further vasoconstriction. This is sufficient to prevent more blood loss in small injuries.

Question 13

What is Coagulation?

Answer 13

Chemical reactions using chemicals and clotting factors produce a thread-like protein called fibrin. Fibrin traps blood cells, platelets and plasma like a mesh, forming a clot. At times mitosis may occur to produce more skin cells.

Question 14

Where does oxygen go during O2 Transport? Describe in terms of inspiration.

Answer 14

3% of oxygen is carried as oxygen gas O2 in the plasma.
97% is attached to red blood cells and forms oxyhaemoglobin.

The lungs have a higher concentration of O2 than the blood at first, and therefore through diffusion, the O2 moves into the blood and attaches to haemoglobin. Then when there is a higher concentration of O2 in the haemoglobin cells than the plasma, some move to the plasma.

Question 15

What is the chemical formula for oxyhaemoglobin?

Answer 15

Hb + O2 ——> HbO2
Haemoglobin + Oxygen Gas ———> Oxyhameoglobin

Question 16

Where does oxygen go during CO2 Transport? Describe in terms of inspiration and expiration.

Answer 16

8% of carbon dioxide is dissolved as CO2 in the plasma.
22% combines with haemoglobin to form carbaminohaemoglobin.
70% is carried in the plasma as hydrogen carbonate ions.

In the lungs during expiration, due to the low concentration of CO2, the carbaminohaemoglobin releases the CO2. ALso since in the blood vessels when the CO2 attaches to the haemoglobin, some move to the plasma there becomes a concentration gradient between the plasma and the haemoglobin cells.

Question 17

What is the chemical formula for carbaminohaemoglobin?

Answer 17

Hb + CO2 ——–> HbCO2
Haemoglobin + Carbon Dioxide ————–> Carbanimohaemoglobin

Question 18

What happens to most of the CO2 in the plasma?

Answer 18

Reacts with water to form carbonic acid, this then dissolves into hydrogen ions and carbonate ions.

Question 19

What is the chemical formula for the conversion of CO2 in the plasma?

Answer 19

CO2 + H2O ——> H2CO3 <————> H+ + HCO3

Question 20

What is an Antigen?

Answer 20

A substance that is capable of stimulating the formation of a antibodies.

Question 21

What is an antibody?

Answer 21

A protein that can combine to antigen and destroy their cells.

Question 22

What types of antigens can be found on erythrocytes?

Answer 22

A and B which are part of the ABO blood type system

Question 23

What are the possible ABO blood types?

Answer 23

Group A
Group B
Group AB
Group O
Each group is inherited

Question 24

What type of antibody does the body produce in relation to the antigen?

Answer 24

The body will produce antibodies for antigens for the antigens it DOES NOT have.

Question 25

What is a blood transfusion?

Answer 25

The transfer of blood or one of the components of blood from one person to another.

Question 26

Why is blood transfusion done?

Answer 26

• Replacement of blood from an injury
• Replacement of blood during surgery
• Treating anaemia (individuals with lower amounts of erythroctyes)

Question 27

What must be considred during a blood transfusion?

Answer 27

That the individual mustn’t receive blood cells with antigens that they produce antibodies for. This is because incompatible blood will be destroyed by the antibodies in the original blood. This leads to agglutination which is clumping together of erythrocytes wich are destroyed.

Question 28

What is the Rh factor

Answer 28

Another type of antigen.

Question 29

What types of Rh are there?

Answer 29

Rh+ or Rh- (none)