The composition and feature of blood

Question 1

What is the difference between arteries and veins?

Answer 1

Arteries are thick blood vessels that move blood away from the heart, handling high blood pressure to ensure even blood flow to the tissues. Veins are thin walled blood vessels that bring the deoxygenated blood back to the heart. The pressure to bring the blood back to the heart is low, so veins have tiny valves to prevent the backflow.

Question 1

What is the heart’s main function?

Answer 1

To distribute oxygenated blood to tissue.

Question 2

What is systole?

Answer 2

Systole refers to the maximum amount of arterial pressure goes up to when you left ventricle of the heart contracts (pushing the blood out of the heart and into the artiers). This is 120mm.

Question 3

What is diastole?

Answer 3

Diastole refers to the minimum amount of arterial pressure between beats (at rest). 80mm.

Question 4

What is hypotension vs hypertension?

Answer 4

Hypotension refers to (too low) and blood does not flow through
capillaries – low O2 high CO2 – weak, dizzy, tired.
 Hypertension (too high) and capillary rupture bleeding,
abnormal clotting and stroke. This can be anything about 130mm.

Question 5

Name the 5 steps of oxygen distribution.

Answer 5

1. The lung provides a vast surface for efficient exchange of O2 and CO2.
2. Oxyhaemoglobin (bright red) is carried from the lungs to the tissue by arteries.
3. CO2 replaces O2 in the tissue
4. Carbaminohaemoglobin (dark red) is carried back to the lungs
5. O2 replaces CO2 in the lung

Question 6

What is oxygen binded to?

Answer 6

The iron in the middle of the heme group.

Question 7

How many heme groups make up 1 haemoglobin?

Answer 7

4 heme groups, meaning 4 iron molecules can bind to 4 oxygen molecules in one haemoglobin.

Question 8

What structure is the heme group called?

Answer 8

Porphyrin

Question 9

What is dependent on the association (binding) and disassociation (releasing) of O2?

Answer 9

Partial pressure.

Question 10

Where is partial pressure the highest for O2 and CO2?

Answer 10

Partial pressure is highest in the lungs for O2 which will make the O2 readily associate with the heme group. Partial pressure is highest for Co2 in the tissues which will make Co2 readily associates with the heme group.

Question 11

What are the other two moelcues that can displace O2 from binding to the heme group?

Answer 11

Cynaide, which is cherry red and carbon monoxide which is pinkish.

Question 12

What is the colour of oxyhemoglobin and Carbaminohaemoglobin?

Answer 12

Oxyhemoglobin is bright red and Carbaminohaemoglobin is dark red.

Question 13

Name the 6 components of blood.

Answer 13

Cells, proteins, lipids, elcrtolyes, vitamins & horomones, and glucose.

Question 14

Name the 4 proteins in blood.

Answer 14

Haemoglobin, albumin, Fibrinogen and Immunoglobulins.

Question 15

Name the 4 types of cells found in blood and describe their function.

Answer 15

1. Erythroid - carries oxygen via the major protein haemoglobin
2. Myeloid – white cells provide innate immunity
3. Lymphoid – white cells provide adaptive immunity
4. Platelets –blood clotting and tissue repair

Question 16

What is the process called to spin blood and separate it’s complements?

Answer 16

Centrifugation

Question 17

What is the Buffy coat?

Answer 17

Buffy coat is made up of WBC and platelets, located in the middle of plasma and RBCS.

Question 18

What is the role of basophils and what do they look like?

Answer 18

Basophils are a type of luceocyte, where they release histamine and are involved in inflammation (innate response). They have blue granules.

Question 19

Name the 3 types of Phagocytic cells.

Answer 19

Nuetrophils which are the most abundant cell and monocyte which has kidney shaped nucleus. Monocytes mature which turns into macrophages.

Question 20

What are Hematopoietic stem cells and name a key feature of them.

Answer 20

Hematopoietic stem cells are cells that give rise to ALL blood cells. A feature is that they can renew themselves (make copies of themselves).

Question 21

Name the two pathways haemopoietic cells arise from
a single multipotent CD34+ stem cell.

Answer 21

1.Myeloid pathway gives rise to red blood cells, platelets, and certain white blood cells like neutrophils, basophils, eosinophils, and monocytes. Basically all the innate immunity.
2. Lymphoid pathway which gives rise to production of lymphocytes, including T cells, B cells, and natural killer (NK) cells. Adaptive immunity.

Question 22

What is Coagulation?

Answer 22

The process of turning fibrinogen into fibrin (blood clotting).

Question 23

What is involved in the process of Coagulation (forming blood clots).

Answer 23

Plasma, which is a viscous substance that has a protein called fibrinogen. Requires an anti-coagulant such as
heparin for coagulation. Serum which is the yellow clear liquid of blood AFTER the blood has been clotted. The fibrin traps red blood cells which appear at the bottom.

Question 24

Explain the Intrinsic pathway (CONTACT) of the Coagulation.

Answer 24

The Intrinsic pathway is caused by contact with surfaces (e.g. a glass tube or a prosthetic heart valve), within the bloodstream. Involves clotting factors: XII, XI, IX, VIII. Factor X (10) which is a key enzyme is activated AFTER the cascade of the other factors. Calicum play a critical role in these steps. If there were no calicium, no blood clotting would occur. After this, the Intrinsic pathway merge into the common pathway.

Question 25

Explain the Extrinsic pathway (TISSUE DAMAGE).

Answer 25

This pathway is caused by tissue damage (e.g. a cut, bruise or infection). Platelets, tissue Factor, V, VI is all summoned. Calcium is needed for this as well. Afterwards, is joins the common pathway.

Question 26

Explain the common pathway.

Answer 26

Common pathway will occur where prothrombin is converted into thrombin. Thrombin is the key enzyme that cleaves fibrinogen to fibrin which cross-links to form a clot. Fibrin then forms a mesh that traps red blood cells and platelets = blood clot.

Question 27

What is the name of the defective clotting disorder?

Answer 27

Haemophilia where one of the clotting factors are defective or missing. Normal clotting cannot occur so there will either be internal bleeding or external bleeding.

Question 28

What is the role of herapin and hurudin?

Answer 28

Parasites and other microbes produce powerful anticoagulants such as herapin and Hirudin which are substances that prevent the key enzyme thrombin from working . Because thrombin cleaves fibrinogen into fibrin, it can't anymore so now blood will not form. Blood will flow more easily.

Question 29

Describe the process of thrombolysis.

Answer 29

Firbin is the protein that holds the clot together. After the wound has healed, the clot has now done its job so fibrin must be removed. Plasminogen gets activated into plasmin which is a key active enzyme that breaks down the clot and dissolves.

Question 30

What activates plasminogen?

Answer 30

Enzyme such as tPA or Streptokinase.

Question 31

What is the usage of tPA and streptokinase in clinical applications?

Answer 31

When you have heart attacks like Myocardial Infarction, PE, DVT, brain these injuries form blood clots when it's not supposed to. To relieve this, tPA and Streptokinase are used to breakdown blood clots which is called the treatment of thromboses.