Fundamentals of Blood and Red Blood Cells Flashcards
What colour is blood plasma?
- yellow
What % of blood plasma is water?
- 92%
What distinguishes if a molecule is organic or inorganic?
- organic = carbon backbone - inorganic = no carbons
What are the main organic compounds?
- lipids - carbohydrates - proteins - nucleic acids (DNA/RNA)
What are the 2 main purposes of inorganic salts in the blood?
- buffer pH - balance osmotic pressure
What are the 3 main functions of blood in the body?
1 - transport O2, glucose, nutrients and vitamins to tissue 2 - transport proteins, hormones and antibodies 3 - remove CO2 and waste metabolites from tissue
Which part of the blood carries proteins?
- plasma - P for plasma and P for protein
What are the 3 layers in blood following centrifugation?
- bottom = RBCs
- middle = WBC and platelets
- top = plasma
What are the 3 main cell types in blood?
1 - red blood cells 2 - white blood cells 3 - platelets
What food do red blood cells resemble?
- doughnuts
Why does the doughnut shape help O2 saturation?
- increases surface area
What is haematocrit?
- the % of red blood cells relative to the total blood volume
Roughly how many white blood cells are in the body in ul?
- 5000-10,000ul
Roughly how many platelets are in the body in ul?
- 250,000 - 400,000ul
In addition to increasing surface area, why is the compliant shape of the red blood cells important?
- can be squashed - can compress to travel down narrow capillaries
What is the normal haematocrit levels in men and women?
- women = 42% - men = 46%
Roughly how many red blood cells are in the body in men and women in ul?
- women = 3.5-5 million ul - men = 4.5-6 million ul
Do red blood cells have a nucleus?
- no
Why do red blood cells not have a nucleus?
- no room - aim is to carry O2 - very few organelles
What is the average life span of a red blood cell?
- 120 days
Old red blood cells can rupture, how are these cells removed?
- macrophages phagocytose them
Roughly what percentage of red blood cells is made up of haemoglobulin?
- 25%
Red blood cells have an asymmetrical membrane, what does this mean?
- the inside and outside of the membrane are different
- intracellularly there is a negative charge
What is the main purpose of the negative charge intracellularly in red blood cells?
- important for cell signalling
What is sceptrin?
- protein inside of red blood cells - forms a mesh like structure as part of the cytoskeleton
What does the sceptrin contribute towards in red blood cell appearance?
- the doughnut shape
What happens if there is an abnormal level of sceptrin in red blood cells?
- deformities of the red blood cells - normally caused by genetic defects
What does the word haematopoiesis mean?
- haema = greek for blood
- poiesis = greek for making something
- making of blood cells
What does Erythropoiesis mean?
- eryth = greek for red
- poiesis = greek for making something
- RBC production
How are platelets formed?
- start as megakaryoblasts
- differentiate to megakaryocytes
- megakaryocytes produce platelets
Where is the site for haematopoiesis, where are all blood cells made?
- in bone marrow - specifically red bone marrow in epiphysis
What is the average amount of blood in the body?
- 5L
What is the red cell production formula?
- red blood cell volume/lifespan for red blood cell - roughly 1/2 of total blood volume = 2250ml - life span = 120 days - so 2250/120 = 18.75ml blood production/day
What is the main hormone that drives early red blood cell development?
- erythopoietin (EPO)
- produced by the kidney
Where is erythopoietin (EPO) made?
- in the kidneys
Why is erythopoietin (EPO) important in red blood cells?
- red blood cell proliferation - red blood cell maintenance
What is a reticulocyte?
- an immature red blood cell
- following enucleation
What is enucleation, and what cells does it occur in?
- the removal of the cell nucleus - red blood cells
How does enucleation occur?
- red blood cells compress forcing out the nucleus
Where do reticulocyte mature?
- in the circulation
How long does it take reticulocytes to mature in the circulation?
- 1-3 days
What can a high reticulocyte level mean?
- blood loss due to trauma
What can a low reticulocyte level mean?
- anemia
- bone marrow is dysfunctional
What does haemoglobin mean?
- ha = heme
- eamia = blood
- globulin = spherical protein