COMPOSITION AND GENERAL FUNCTIONS OF BLOOD

Question 1

what are the 3 key functions of blood?

Answer 1

• transport
• immune response
• coagulation

Question 2

what does blood transport?

Answer 2

• O2, water, nutrients
• CO2, waste products
• Ions
• Heat
• Hormones
• Immune cells
• Coagulation factors (to stop us from bleeding)

Question 3

what is in the immune function of blood?

Answer 3

• white blood cells: fight pathogens, respond to infection and allergy
• immunoglobulins: big proteins

Question 4

what are the factors for coagulation?

Answer 4

• platelets
• coagulation factors in plasma

Question 5

what is the percentage of plasma in blood?

Answer 5

55%

Question 6

what is in plasma?

Answer 6

• 92% of water
• 1% of other solutes (electrolytes and organic nutrients/wastes)
• 7% of proteins

Question 7

what is the coagulation factor in plasma?

Answer 7

a plasma protein called fibrinogen

Question 8

what is the immune factor in plasma?

Answer 8

globulin

Question 9

what are the content in the 45% formed elements of blood?

Answer 9

• 99% RBC
• <0.1% of white blood cell for defense mechanism
• <0.1% of platelets that participate in clotting

Question 10

what is the formation of blood cells called?

Answer 10

haematopoiesis

Question 11

what is blood stem cell also called?

Answer 11

hemocytoblast

Question 12

where can we find the blood stem cells?

Answer 12

red bone marrow

Question 13

what are the 2 types that blood stem cells differentiate into?

Answer 13

• lymphoid stem cells
• myeloid stem cells

Question 14

what does lymphoid stem cells differentiate into?

Answer 14

lymphoid cells

Question 15

what does myeloid stem cells differentiate into?

Answer 15

• white blood cells
• platelets
• red blood cells

Question 16

what does colony-stimulating factor do?

Answer 16

stimulate the formation of white blood cells, affecting on the progenitor cells

Question 17

what does leukemia means?

Answer 17

over-production or under-production of white blood cells

Question 18

what is megakaryocyte?

Answer 18

a pre-platelets structure, formed from myeloid stem cell and growing until to big and explode –> platelets

Question 19

what is the shape of RBC and how does that help the function?

Answer 19

• biconcave disc shape
• large surface area/volume ratio –> more access, nothing is too far from the surface –> allows an efficient diffusion of gas
• flexible for movement through narrow vessels/capillaries because can fold and squeeze without harming the structure

Question 20

what is haemoglobin?

Answer 20

• protein found in rbc, has 4 haem units with iron as part of the structure to bind oxygen
• each haem unit binds with 1 oxygen

Question 21

how many oxygen can a haemoglobin bind with?

Answer 21

4

Question 22

what is haematocrit?

Answer 22

the fraction of blood occupied by the red cells (a.k.a packed cell volume - PCV)

Question 23

________1_________ determines how much O2 can be carried in the blood.
______2_____ is when our blood has low haemoglobin levels –> blood carries _____3_____ oxygen, therefore _______4____ the amount of O2 delivered to tissue and reduce the exercise ability

Answer 23

1: haemoglobin concentration
2: anaemia
3: less
4: reduce

Question 24

why can we have anaemia?

Answer 24

deficiency of Fe in diet

Question 25

what is EPO and what does it do?

Answer 25

EPO = erythropoiesis: a factor that stimulate that RBC production

Question 26

describe how EPO affects the system?

Answer 26

low oxygen level detected in blood –> kidneys sensed the depression of blood lvl –> kidney releases EPO –> EPO circulates to bone marrow –> stimulate the production of RBCs –> blood can carry more oxygen

Question 27

why does male have more RBCs than female?

Answer 27

the process of stimulation RBCs with EPO is augmented by testoterone - an abundant hormone can be found in male