BIOL 273 - Unit 4.5

Question 1

4 major components of blood

Answer 1

1. Plasma
2. Red blood cells
3. White blood cells
4. Platelets

Question 2

Plasma

Answer 2

luid portion of the blood (water, proteins, nutrients, hormones)

Question 3

Red blood cells , whats its other name , what does it contain , major function

Answer 3

erythrocytes
- most abundant cells in blood
- contain protein haemoglobin
- major function: gas transport
- lack nucleus and mitochondria

Question 4

White blood cells, whats its other name and overall function

Answer 4

leukocytes , immune system functionality

Question 5

What are the 5 types of white blood cells (NLMEB)

Answer 5

1. Neutrophils
2. Lymphocytes
3. Monocytes
4. Eosinophils
5. Basophils

Question 6

Mature form of monocytes

Answer 6

macrophage

Question 7

What are considered the professional phagocytes in the body

Answer 7

Macrophages and neutrophils

Question 8

Platelets , its other name, function

Answer 8

thrombocytes
- involved in blood clotting
- derived from megakaryocytes - pinch off and have no nucleus

Question 9

Main component of haemoglobin subunit

Answer 9

iron

Question 10

What is the purpose of haemoglobin/oxygen saturation

Answer 10

response to changes in high temp, PCO2 and H+
- allowing more O2 to be released

Question 11

Haematopoiesis

Answer 11

production of blood cells in red bone marrow
- where pluripotent haematopoietic stem cell are found

Question 12

Describe the process of haematoposiesis

Answer 12

pluripotent haematopoietic stem cell can develop into many different cell types
- Progenitor cells are committed to one or two cell types

Question 13

Cytokines

Answer 13

involved in the the path of haematopoiesis
- proteins/signalling molecules that allow progenitor cells to undergo maturation

Question 14

Leukopoieses

Answer 14

• process of haematopoiesis; formation of leukocytes (white blood cells)
• regulated by colony stimulating factors (CSFs)
• tend to regulate further leukocyte production (ex. during active bacterial infection)

Question 15

Thrombopoiesis

Answer 15

• process of haematopoiesis: formation of thrombocytes
• growth and maturation are regulated by cytokine thrombopoitein

Question 16

Erythropoiesis

Answer 16

• process of haematopoiesis; formation of red blood cells
• regulated by erythropoietin (EPO) (made in kidneys)
• EPO synthesis and release is regulated by hypoxia

Question 17

Haemostasis

Answer 17

prevents blood loss from damaged vessels - need to maintain the integrity of the blood vessels
- flow of body cannot be turned off, need to be strong to withstand damage

Question 18

First part of haemostasis: Vascular spasm

Answer 18

Vascular spasm- blood vessel contracts , pressure on a bleeding wound
- narrows lumen vessel

Question 19

Second part of haemostasis: Platelet pluf to temporarily block break

Answer 19

Platelet plug to temporarily block break:
- platelets are activated by chemicals released from the injury site and by contact with underlying collagen
- releases cytokines to release more platelets
- framework for clotting

Question 20

Third part of haemostasis: Blood clot to seal the break

Answer 20

Blood clot to seal the break - result of coaulation cascade
- inactive plasma proteins are activated by exposure to factor XII to collagen (intrinisc pathway) or exposure to tissue factor III (extrinsic pathway)
- cascade occurs
- both pathways merge into the common pathway

Question 21

What does the merging to the common pathway during haemostasis lead to

Answer 21

the activation of thrombin which cleaves fibrinogen into fibrin

Question 22

Thrombin

Answer 22

activates factor XIII which cross-links the fibrin into long fibres that intertwine to form a fibrin network
- reinforcing the platelet plug making it a clot

Question 23

Describe the healing process of Haemostasis

Answer 23

enzyme plasminogen is converted into plasmin
- enzyme plamin dissolves the clot ; fibrinolysis