Lymphatic Haemotology (week 3)

Question 1

What is the function of blood?

Answer 1

1. Transport - O2,Co2, wastes.
2. Regulation - pH, body temperature, body fluid.
3. Protection - blood loss & infection.

Question 2

What is the benefit of RBC’s not containing mitochondria?

Answer 2

By RBC’s not containing mitochondria, it generates ATP anaerobically (without O2), therefore, they do not use up any of the O2 they transport.

Question 3

What is the benefit of RBS’s biconcave disc shape?

Answer 3

A biconcave disc has much greater surface area for the diffusion of gas molecules into and out of the RBC than would, say, a sphere or cube.

Question 4

What is haemoglobin composed of?

Answer 4

1. Globin (composed of 2 alpha & 2 beta polypepetide chains).
2. Heme - ring like, is bound to 4 chains.
3. Iron - At centre of each heme ring, that can combine reversibly with one oxygen molecule, allowing for each haemoglobin to bind 4 oxygen molecules.

Question 5

What are the functions of haemoglobin?

Answer 5

1. O2 & CO2 transport.
2. Regulation of blood flow and blood pressure - the gaseous hormone Nitrtic Oxide (NO) produced by the endothelial cells that line the blood vessels, binds to haemoglobin. Under some circumstances, haemoglobin releases NO. This causes vasodilation, which improves blood flow & enhances oxygen delivery to cells near the site of NO release.

Question 6

Why does a RBC have a short life of around 120days?

Answer 6

• Since the wear and tear their plasma membranes undergo as they squeeze through blood capillaries. Without a nucleus and other organelles, RBC’s cannot synthesize new components to replace damaged ones.
• Plasma membrane also become more fragile with age and the cells are more likely to burst, especially as they squeeze through narrow channels in the spleen.

Question 7

What happens to the ruptured RBC’s?

Answer 7

Ruptured RBC’s are removed from circulation and destroyed by fixed phagocytic macrophages in the spleen and liver, and the break down products are recycled and used in numerous metabolic processes, including the formation of new RBC’s.

Question 8

What is the difference between interstitial fluid and lymph?

Answer 8

The major difference between the two is location. Lymph is located within the lymphatic vessels & lymphatic tissue.

Question 9

What are the functions of the lymphatic system?

Answer 9

1. Drains excess fluid - Lymphatic vessels drain excess interstitial fluid from tissue spaces & return it to the blood.
2. Transports dietary lipids - Lymphatic vessels transport lipids and lipid-soluble vitamins (A, D, E, K) absorbed by the GI tract.
3. Carries out immune response - Lymphatic tissue intiates highly specific responses directed against particular microbes or abnormal cells.
4. Return lost plasma proteins & plasma to the bloodstream - because most plasma proteins are too large to leave the blood vessels, interstitial fluid contains only a small amount of protein. Proteins that do leave blood plasma cannot return to the blood by diffusion because the concentration gradient opposes such movement. Therefore, plasma proteins move into lymphatic capillaries to be sent back to the bloodstream.

Question 10

What are lacteals?

Answer 10

Specialized lymphatic capillaries that carry dietary lipids into lymphatic vessels & ultimately in the blood. The prescence of these lipids causes the lymph draining from the small intestine to appear creamy white, and such lymph is referred to as chyle. Elsewhere lymph is clear, pale-yellow fluid.

Question 11

What is the function of a spleen?

Answer 11

1. A major collection of lymph tissue in the body.
2. Recyle RBCs
3. WBC
4. T-cell proliferation
5. Blood reserve.

Question 12

How many pairs of tonsils are in the body?

Answer 12

5 pairs. Involved in immune response.

By reducing dairy diet is shown to improve function and immunity.

Question 13

What is the name of the disorder when there is low haemoglobin/RBC?

Answer 13

Anemia (Low O2)

Question 14

What is the name of the disorder when there is excess haemoglobin/RBC? What is a common cause?

Answer 14

Polycythaemia (Excess O2)

Common cause: Spleen disorder. (Investigate)

Question 15

What are some common investigations used for a blood check?

Answer 15

1. Full blood count (FBC)
2. Haemoglobin
3. Blood indicies - MCV (Mean Cell Volume), MCHC (Mean Corpuscular Haemoglobin concentration), PCV (Packed Cell Volume), MCH (Mean Corpuscular Haemoglobin).
4. Total WBC count
5. Differential count of WBC (Neutrophils, basophils, esonophils ect)
6. Platelet count
7. Erythrocyte sedimentation rate (ESR)
8. CRP (C-Reactive Protein)
9. Blood Film examination (shape of RBCs - macrocytic/ microcytic/ sickle cell anemia)
10. Bone Marrow examination - (cell maturation, when suspecting leukemia)
11. Investigation of the coagulation system (Bleeding disorders, thrombotic disorders, patients on anti-coaglant medication)

Question 16

What is anemia?

Answer 16

Low haemoglobin level in the blood.

Question 17

What are the common causes of anemia?

Answer 17

1. Increased demand - exercise
2. Low production
3. Diet - protein, iron, fats
4. Blood loss - Premenopausal women or heavy menstruation = Low iron.
5. Chronic disease/illness
6. Liver issue
7. Malabsorption - Loss of iron in faeces (black/red faeces)

Question 18

What are the common symptoms of anemia?

Answer 18

Pale complexion, pale nails, blue ring outside iris, palm crease is pale when pulled back, breathing, sighing, sleepy, fatigue, weak.

Question 19

What is the name of the disorder when there is iron overload?

Answer 19

Haemocromatosis - absorbs too much iron from an ordinary diet.

Question 20

What is leukopenia?

Answer 20

Low WBC count.

Question 21

What is Neutropenia?

Answer 21

Low neutrophil count

Question 22

What is Lymphopenia?

Answer 22

Low lymphocyte count

Question 23

What is Leucocytosis?

Answer 23

High WBC count.

Question 24

What is Neutrophilia?

Answer 24

High neutrophil count.

Question 25

What is Lymphocytosis?

Answer 25

High lymphocyte count.

Question 26

What is Thrombocytopenia?

Answer 26

Low platelets

Question 27

What are the common causes of thrombocytopenia and what are the symptoms?

Answer 27

Causes:
1. Bone marrow disorders
2. Increased consumption of platelets.
Symptoms:
1. Easy bruising
2. Haemorrhage

Question 28

What is Thrombocytosis?

Answer 28

High platelets

Question 29

What are the common causes of Thrombocytosis and what are the symptoms?

Answer 29

Causes:
1. Reactive thrombocytosis
2. Malignant thrombocytosis.
Symptoms:
1. Increased clotting, increasing the risk of stroke.

Question 30

What is venous thrombosis, what are the common causes and what medication are commonly used for treating this condition?

Answer 30

Definition: Swollen leg on one side.
Causes: Medication, immobility, long flights, disability, pregnancy, diabetes
Thrombolytic Medications: Heparin, warfarin, streptokinase.

Question 31

What is lymphadenopathy and what are the causes?

Answer 31

Definition: Enlargement of lymph nodes.
Causes: Infection, neoplastic, sarcoidosis, amyloidosis (Type of bone marrow disease - abnormal deposits of the protein amyloid in the body), medications side effects.

Question 32

What is splenomegaly and what are the common causes? How is this treated?

Answer 32

Definition: Enlargement of the spleen.
Causes: Congestive, storage disease, associated with liver disease, anemia, malignancy.
Treatment: Often spleen is removed.

Question 33

What are the consequences of removing a spleen?

Answer 33

1. Increased risk of infection - therefore patients recieve a flu-vaccine every year.
2. Injury to near by organs such as the pancreas, stomach and colon.
3. Pus collection under the diaphragm