lecture 13 - blood composition & function

Question 1

What are the 3 general functions of blood?

Answer 1

Transport, immune response, coagulation

Question 2

What things does the blood transport (7)?

Answer 2

O2 & nutrients, CO2 & wastes, ions, heat, hormones, immune cells, coagulation factors

Question 3

The ions transported in the blood determine what?

Answer 3

Blood pH

Question 4

Why does the blood carry heat?

Answer 4

Water (blood’s main constituent) is able to absorb a lot of heat that is the product of oxidative reactions in cells.

Question 5

What is the function of blood transported hormones?

Answer 5

Co-ordinate organ activity

Question 6

What is the immune function of blood?

Answer 6

Fight infection via white blood cells

Question 7

What is the coagulation function of blood?

Answer 7

Platelets and coagulation factors in the plasma prevent bleeding.

Question 8

What is the body’s blood volume proportional to?

Answer 8

Lean body mass

Question 9

What is the ratio of blood to kilogram of body mass?

Answer 9

60-80mL per kg

Question 10

What are the 2 major components of blood?

Answer 10

Plasma, formed elements

Question 11

What are the 3 components of plasma?

Answer 11

Plasma Proteins, other solutes, water

Question 12

What are the 4 types of plasma proteins found in blood plasma?

Answer 12

Albumins, globulins, fibrinogens, enzymes & hormones

Question 13

What is the role of albumins in the blood plasma?

Answer 13

Maintains osmotic pressure to prevent blood cells from absorbing water and swelling/rupturing

Question 14

What is the role of globulins in blood plasma?

Answer 14

Involved in the immune response

Question 15

What is the role of fibrinogen?

Answer 15

Coagulation factor

Question 16

What are the 3 key solutes found in plasma?

Answer 16

Electrolytes, organic nutrients, organic wastes

Question 17

What is the role of the electrolytes in blood plasma?

Answer 17

Maintain pH and ion balance

Question 18

What is the role of dissolved organic nutrients in blood plasma?

Answer 18

Support cell function and are carried to the periphery

Question 19

What is the role of organic wastes in blood plasma?

Answer 19

Cell waste products are removed via the blood

Question 20

What percentage of plasma is made up of water?

Answer 20

~90%

Question 21

What are the 3 formed elements of blood?

Answer 21

Platelets, white blood cells, red blood cells

Question 22

What are platelets?

Answer 22

Cell fragments that participate in clotting to stop bleeding

Question 23

What are white blood cells?

Answer 23

Immune response and defensive mechanisms that destroy pathogens

Question 24

What is the most common cell in the blood?

Answer 24

Red blood cells

Question 25

What is the name for the formation of blood cells?

Answer 25

Haematopoiesis

Question 26

Where does haematopoiesis occur?

Answer 26

In red bone marrow

Question 27

What is the progenitor stem cell for all blood cells?

Answer 27

Haemocytoblasts

Question 28

What type of stem cell do red blood cells develop from?

Answer 28

Myeloid stem cells

Question 29

What is the alternative name for red blood cells?

Answer 29

Erythrocytes

Question 30

Why do red blood cells have a large surface area?

Answer 30

For efficient diffusion of gases

Question 31

Why are red blood cells flexible and rounded?

Answer 31

For free movement through narrow capillaries

Question 32

What is the name for the shape of a red blood cell?

Answer 32

Biconcave disc

Question 33

What proportion of RBC mass consists of haemoglobin?

Answer 33

1/3

Question 34

How does haemoglobin bind oxygen?

Answer 34

Uses iron on 4 haem units to bind 4 oxygen per haemoglobin

Question 35

What is hematocrit?

Answer 35

The part of centrifuged blood that contains the red blood cells

Question 36

What is the alternative name for hematocrit?

Answer 36

Packed cell volume (PCV)

Question 37

Do men or women tend to have a higher proportion of hematocrit in their blood?

Answer 37

Men

Question 38

What is anaemia, in terms of hematocrit level?

Answer 38

Low hematocrit due to iron deficiency

Question 39

What is polycythemia, in terms of hematocrit level?

Answer 39

High hematocrit causing the blood to become thick

Question 40

What is erythropoiesis?

Answer 40

The generation of red blood cells

Question 41

What stimulates erythropoiesis?

Answer 41

Erythropoietin (EPO)

Question 42

What is erythropoietin?

Answer 42

A hormone that simulates red blood cell production

Question 43

What hormone has a secondary role in augmenting red blood cell production?

Answer 43

Testosterone

Question 44

Why do athletes train at high altitude?

Answer 44

There is less O2 a available so the body adapts by producing more EPO which increases red blood cell count and therefore O2 capacity, leading to increased performance.

Question 45

What are the short term effects of altitude on the body?

Answer 45

Increased HR and Breathing rate

Question 46

How does the body detect low blood O2 levels due to high altitude?

Answer 46

The kidneys detect O2 levels

Question 47

What are the long term mechanism employed by the body at high altitude?

Answer 47

Kidneys release EPO to stimulate the production of red blood cells, increasing hematocrit.