Unit 4 - Part 2

Question 1

Plasma

Answer 1

The fluid portion of blood (55%). Contains water, proteins, nutrients, and hormones.

Question 2

Leukocytes

Answer 2

White blood cells. Function in immune response.

Question 3

Erythrocytes

Answer 3

Red blood cells. Biconcave in shape. Most abundant cell in the blood. Contains hemoglobin. The major function is gas transport (O2 and CO2). For mammals it lacks a nucleus and mitochondria.

Question 4

Thrombocytes

Answer 4

Platelets. Involved in blood clotting. Derived from megakaryocytes (pinched off and have no nucleus).

Question 5

Haematopoiesis

Answer 5

The creation of blood cells. Occurs in the red bone marrow.

Question 6

Haemoglobin

Answer 6

Required for red blood cells to bind oxygen. A large complex molecule made up of 4 protein chains/globins. Each subunit contains a certain iron molecule.

Question 7

Red Bone Marrow

Answer 7

Where all blood cells are produced.

Question 8

Erythropoietin

Answer 8

Regulates erythropoiesis. Is usually called a hormone but it is a cytokine. A glycoprotein made and released primarily in the kidneys. Its synthesis and release is regulated by hypoxia (low oxygen).

Question 9

Cytokines

Answer 9

Released by leukocytes that further regulate leukocyte production. Are released into the venules.

Question 10

Colony Stimulating Factors (CSFs)

Answer 10

Regulate the formation of leukocytes. Are released by endothelial cells, marrow fibroblasts, and white blood cells. They induce cell division and cell maturation in stem cells. Are released into the venules.

Question 11

Megakaryocytes

Answer 11

Parent cells that produce platelets (thrombocytes). Undergo mitosis up to 7 times without undergoing nuclear or cytoplasmic division. Results in a polyploid cell with a lobed nucleus. Reside in the bone marrow and extend their outer edges through the endothelium (cells lining the blood vessels) into the blood stream.

Question 12

Platelet

Answer 12

Small cell fragments in the blood that are essential for blood clotting, preventing excessive bleeding, and wound healing. Formed from megakaryotes.

Question 13

Haemostasis

Answer 13

The process of fixing damaged blood vessels.

Question 14

Haemorrhage

Answer 14

Blood leaving from a broken blood vessel.

Question 15

Platelet Plug

Answer 15

Formed by activated platelets sticking together.

Question 16

Thrombin

Answer 16

Converts fibrinogen into fibrin.

Question 17

Factor XIII

Answer 17

Used in the cross-linking of fibrin to form the clot.

Question 18

Fibrinogen

Answer 18

The inactivated form of fibrin.

Question 19

Fibrin

Answer 19

What forms the cross-linked structure for the clot.

Question 20

Plasmin

Answer 20

An enzyme used to dissolve blood clots.

Question 21

Fibrinolysis

Answer 21

When the enzyme plasmin dissolves the blood clot.

Question 22

Platelet Activation

Answer 22

Occurs when there is damage to the walls of the circulatory system.

Question 23

Regulation of Blood Cell Production

Answer 23

White Blood Cells - regulated by colony-stimulating factors.
Platelets - regulated by cytokine thrombopoietin.
Red Blood Cells - regulated by erythropoietin.

Question 24

Haemoglobin Oxygen Saturation Curves

Answer 24

Shows the relationship between the partial pressure of oxygen and the percent saturation of hemoglobin.

Question 25

Blood

Answer 25

The circulating component of extracellular fluid responsible for carrying substances around the body.

Question 26

Components of Blood

Answer 26

1) Plasma 2) Red Blood Cells/Erythrocytes 3) White Blood Cells/Leukocytes 4) Platelets/Thrombocytes

Question 27

Types of Leukocytes

Answer 27

1) Lymphocytes 2) Monocytes/Macrophage 3) Granulocytes 3a) Neutrophils 3b) Eosinophils 3c) Basophils (mast cells)

Question 28

Granulocytes

Answer 28

3 types. Full of proteins.

Question 29

Buffy Coat

Answer 29

1% of blood. Contains white blood cells and platelets.

Question 30

Hematocrit

Answer 30

45% of blood. Contains red blood cells.

Question 31

Anemia

Answer 31

A lack of hemoglobin synthesis due to low dietary iron consumption.

Question 32

Right Shift

Answer 32

Increase in temperature, increase in partial pressure of CO2, and decrease in pH. Causes lower binding affinity.

Question 33

Left Shift

Answer 33

Decrease in temperature, decrease in partial pressure of CO2, and increase in pH. Causes higher binding affinity.

Question 34

Pluripotent Haematopoietic Stem Cell

Answer 34

The precursor of all blood cells (the starting stem cell).

Question 35

Progenitor Cells

Answer 35

The daughter cell of a stem cell that becomes differentiated.

Question 36

Leukopoiesis

Answer 36

The formation of leukocytes which is regulated by the colony-stimulating factors (CSFs).

Question 37

Cytokine Thrombopoietin (TPO)

Answer 37

Regulate the growth and maturation of megakaryocytes.

Question 38

Thrombopoiesis

Answer 38

The process of the ends of megakaryocytes being pinched off to form platelets.

Question 39

Erythropoiesis

Answer 39

The formation of red blood cells.

Question 40

Vascular Spasm

Answer 40

Similar to putting pressure on a bleeding wound. Done by vasoconstrictive paracrines released by damaged endothelium of the blood vessel.

Question 41

Stages in Haemostasis

Answer 41

1) Vascular spam which decreases blood flow by increasing resistance which promotes the formation of the platelet plug. 2) Exposed collagen from the sub-endothelial layer allows platelets to stick and become activated. Cytokines are released activating more platelets. Activated platelets form the platelet plug. 3) A blood clot is formed by the coagulation cascade.

Question 42

Coagulation Cascade

Answer 42

Starts with two pathways, the intrinsic and extrinsic, and ends up merging into the final common pathway.

Question 43

Intrinsic Pathway

Answer 43

Activated by damage to the vessel wall. Inactive plasma proteins are activated by exposure to factor XII to collagen. Ends with factor X.

Question 44

Extrinsic Pathway

Answer 44

Activated by trauma to extravascular cells. Inactive plasma proteins are activated by exposure to tissue factor III released from damaged cells. Ends with factor X.

Question 45

Common Pathway

Answer 45

Factor X leads to the activation of thrombin from prothrombin which cleaves fibrinogen into fibrin. Thrombin also activates factor XIII which cross-links the fibrin into long fibres that intertwine to form a fibrin network. Intertwined fibres reinforce the platelet plug making it a clot. Excessive clotting produces a thrombus, a clot which can block blood vessels.

Question 46

Healing From a Damaged Blood Vessel

Answer 46

Plasminogen is converted into plasmin by either thrombin or tissue plasminogen activator (tPA). The enzyme plasmin dissolves the clot by fibrinolysis. As repairs progress the clot slowly shrinks.