Lecture 13 - Lol Yay Flashcards
Three general functions of blood
- transport
- immune response
- coagulation
What does the blood transport?
- O2, water, nutrients
- CO2 (as it acidising things), waste products (urea, contains nitrogen)
- ions associated with pH and homeostasis
- heat - a product of oxidative reactions in cells
- hormones - co-ordinate the activities of organs of the body
- immune cells
- coagulation factors
What does the immune function of the blood consist of?
Fighting infection and production of the immune response
- white blood cells (cellular components)
- immunoglobulins (proteins / chemicals)
What is coagulation and how does it do it
- stop bleeding
- Platelets (formed component) (create mesh-network)
- Cagulation factors in plasma (clog up the mesh network)
How much blood is in a person
70kg person has about 5L of blood
Blood volume is in proportion to…
… lean body mass
50% of blood is _____ and the other 50% is ____
-plasma
-formed elements
Plasma is made form mostly
Water (92%)
3 main components of plasma
- WATER (92%)
- Plasma proteins (7%)
- albumins
- globulins
- fibrinogen
- enzyme and hormone - Other solutes (1%)
- electrolytes
- organic nutrience
- organic waste
What do albumins do and what section do they fit into?
- maintain osmotic pressure
- plasma - plasma proteins
What do globulins do and what section do they fit into
- immune response
- plasma - plasma proteins
What are fibrinogens and what section do they fit into?
- coagulation factor
- plasma - plasma proteins
What are enzymes and hormones and what section are they under
- lots of functions; varies by person
What did electrolytes do and what section do they belong to?
- maintain pH and ion balance
- plasma - other solutes
What are organic nutrients and what section
- what cells need to function
- Plasma - other solutes
What are organic wastes and what section do they belong to
- things cells get rid of
- plasma - other solutes
Function of water in plasma
- can hold a lot of heat
3 parts of formed elements
- platelets <0.1%
- white blood cells <0.1%
- red blood cells 99.9%
What are platelets and what part of blood are they found in
- cell fragments that participate in clotting to stop bleeding
- formed elements
What do white blood cells do and what part of blood are they found in
- immune responses and defence mechanisms; these seek and destroy invading pathogens
- formed elements
What are red blood cells and what part of blood are they found in
- by far the most common cell found in blood; highly specialised for transport of oxygen
What is haematopoiesis ?
The formation of blood cells
Where is haematopoiesis initiated
In red bone marrow, which contains blood stem cells
Blood stem cells are the ______ for all blood cells
Blood stem cells are the progenitors for all blood cells
Blood cell differentiation from stem cell
- depending on environment they can go down different lines
When you have complex systems…
…. There is a lot of room for error - blood cancers etc
Blood stem cells go down various pathways to form various formed elements, white blood cells, platelets or red blood cells
True adn real
What do platelets from from
Megokaryocytes that break down into smaller fragments
Pathway of red blood cell from stem cell
Stem cell —-> myeloid stem cells - stimulated by erythropoietin (EPO) ——- > erthroblast stages (nucleus ejected) ——> reticulocyte ———> red blood cell
Red blood cells dont have
Nucleus
Organnelse
- don’t need repordcative mechanism to decide as a new one is just made each time
What is RBC formation stimulated by?
EPO
Function of RBC - erythrocytes
- oxygen transport
How the RBC structure relates to its funciton
Bioc cave disc shape
- larger SA:V ratio
- allows for effecient diffusion of gasses
- flexibility for movement through narrow capillaries (shape allows them to fold up)
- many throughout body and packed with haemoglobin
Red blood cells contain large amounts of…
Haemoglobin (4 protein chains)
How much of the RBC weight is contributed by haem
One third
What does the haeme use is its structure to bind oxygen?
Iron
How many oxygen molecules can haemoglobin bind?
Four haem units, so each haemoglobin can bind four oxygen molecules
RBC doesnt divide or carry out processed - so there are jam packed with haemoglobin
Ye
What is the haematopocrit / packed cell volume
- the fraction of blood occupied by the red cells
What is the fraction of blood occupied by the red blood cells called?
Haematocrit or packed cell volume (PCV)
How do you seperate blood into it’s main components?
In a centrifuge
What does a centrifuge do?
Separates blood into its main components
How much volume do red blood cells take up
Typicallly red blood cells make up about 50% of blood volume
I.e haematocrit ~0.5
The rest is plasma and white blood cells
Haematocrit
Haemoglobin concentration determines…
… how much O2 can be carried in the blood
What happens when haemoglobin levels are low?
Anaemia
What’s happening when you’re anaemic
= low haemoglobin levels
- blood carries less O2
- reduces amount delivered to tissues
- reduces excercie ability
Fe deficient in diet
- can measure this to determine red blood cells instead of centrifuge
What does reduced Fe lead to
Anaemia
Erythropoiesis
Generation of red blood cells
All blood cells are derived from..
..a common stem cell
What is RBC production stimulated by?
Erythropoietin (EPO)
What is required to make haemoglobin ?
Iron
Erythropoiesis is augmented by…
…testosterone
How does Erythropoiesis happen?
- if low level of oxygen in blood…
- kidneys sense that oxygen levels in the blood are depressed
- kidneys release EPO
- EPO circulates to bone marrow
- stimulates the production of more RBCs => blood can carry more O2
What causes low levels of O2 in blood?
- anaemia
- respiratory problem
- HIGH ALTITUDE
- if athlete at high altitude - provide more haemoglobin as not enough oxygen - then when u return to normal - haemoglobin remains high
EPO to increase athletic performance
- erythropoietin
- erythrocytes
- increased O2 capacity
- increases performance
- MAKES SLUDGY BLOOD
The plasma and formed elements in blood are specialised to allow blood to perform three functions of transport, immune response and coagulation
Yep
