COMPOSITION AND GENERAL FUNCTIONS OF BLOOD Flashcards
what are the 3 key functions of blood?
- transport
- immune response
- coagulation
what does blood transport?
- O2, water, nutrients
- CO2, waste products
- Ions
- Heat
- Hormones
- Immune cells
- Coagulation factors (to stop us from bleeding)
what is in the immune function of blood?
- white blood cells: fight pathogens, respond to infection and allergy
- immunoglobulins: big proteins
what are the factors for coagulation?
- platelets
- coagulation factors in plasma
what is the percentage of plasma in blood?
55%
what is in plasma?
- 92% of water
- 1% of other solutes (electrolytes and organic nutrients/wastes)
- 7% of proteins
what is the coagulation factor in plasma?
a plasma protein called fibrinogen
what is the immune factor in plasma?
globulin
what are the content in the 45% formed elements of blood?
- 99% RBC
- <0.1% of white blood cell for defense mechanism
- <0.1% of platelets that participate in clotting
what is the formation of blood cells called?
haematopoiesis
what is blood stem cell also called?
hemocytoblast
where can we find the blood stem cells?
red bone marrow
what are the 2 types that blood stem cells differentiate into?
- lymphoid stem cells
- myeloid stem cells
what does lymphoid stem cells differentiate into?
lymphoid cells
what does myeloid stem cells differentiate into?
- white blood cells
- platelets
- red blood cells
what does colony-stimulating factor do?
stimulate the formation of white blood cells, affecting on the progenitor cells
what does leukemia means?
over-production or under-production of white blood cells
what is megakaryocyte?
a pre-platelets structure, formed from myeloid stem cell and growing until to big and explode –> platelets
what is the shape of RBC and how does that help the function?
- 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
what is haemoglobin?
- 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
how many oxygen can a haemoglobin bind with?
4
what is haematocrit?
the fraction of blood occupied by the red cells (a.k.a packed cell volume - PCV)
________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
1: haemoglobin concentration
2: anaemia
3: less
4: reduce
why can we have anaemia?
deficiency of Fe in diet
what is EPO and what does it do?
EPO = erythropoiesis: a factor that stimulate that RBC production
describe how EPO affects the system?
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
why does male have more RBCs than female?
the process of stimulation RBCs with EPO is augmented by testoterone - an abundant hormone can be found in male
