Blood, tissue fluid, and lymph Flashcards
What are the three components that travel in the blood vessels?
Blood, tissue fluid and lymph
What is the name of the yellow liquid that makes up blood?
Plasma
Plasma acts as a transport function. What are the components that plasma carries?
- dissolved glucose
- amino acids
- mineral ions
- hormones
- large plasma proteins (albumin, fibrinogen, globulins)
- red blood cells
- white blood cells
- Platelets
What components of the blood are involved in the transport functions?
Red blood cells and plasma
What are the three types of large plasma proteins that are in the blood?
Albumin Fibrinogen Globulins
What is the albumin protein useful for?
Maintaining the osmotic potential of the blood
What is the fibrinogen protein useful for?
It is important in blood clotting
What is the globulins protein involved in?
Transport and the immune system
What gives the blood its red appearance?
The red blood cells
Where did platelets originate from?
Platelets are fragments of large cells called megakaryotcytes.
Where are megakaryotcytes found?
In red bone marrow
What are platelets involved in?
They are involved in the clotting mechanism of the blood
How much of the blood volume is plasma?
55%
What are the 7 functions of the blood?
- To bring oxygen to and from the respiring cells
- Digested food from the small intestine
- Nitrogenous waste products from the cells to the excretory organs
- Chemical messages (hormones)
- Food molecules from storage compounds to the cells that need them
- Platelets to damaged areas
- Cells and antibodies involved in the immune system
- Maintenance of body temperature
- Acts as a buffer to minimise pH changes
What passes through the fenestrations in the capillary wall?
The substances dissolved in plasma (except the large plasma proteins)
The plasma proteins, particularly albumin, have a osmotic affect. What does this mean?
They give the blood in the capillaries a relatively high solute potential and thus a relatively low water potential compared to the surrounding fluid.
Because of the relatively low water potential inside the capillaries what happens to the water outside of the capillaries?
The water has a tendency to move into the blood in the capillaries from the surrounding fluid by osmosis
What is osmosis?
It is the movement of water across a partially-permeable membrane, from an area of high water concentration to an area of low water concentration.
What is the symbol for water potential?
ψ
What is water potential?
It is measured in kilopascals (kPa) and is represented by the Greek letter Psi (Ψ). Water potential is never positive but has a maximum value of zero, which is that of pure water at atmospheric pressure.
What is solute potential?
The component of water potential that is due to the presence of solute molecules.
What does potential refer to in biology?
potential refers to a pressure that determines the direction a given substance will flow.
What is the value of oncotic pressure?
-3.3kPa
What is oncotic pressure?
The tendency of water to move into the blood via osmosis
What is hydrostatic pressure?
The pressure from the surge of blood that occurs every time the heart contracts
At the arterial end of the capillary, the hydrostatic pressure forcing fluid out of the capillaries is relatively high? What is the pressure?
4.6KPa
As the hydrostatic pressure is higher than the oncotic pressure attracting water in by osmosis what happens to the fluid in the capillaries?
It is squeezed out of the capillaries
What is tissue fluid?
The fluid that is squeezed out of the capillaries and fills the spaces between the cells
What is the composition of tissue fluid?
It is the same as plasma but without the red blood cells or the plasma proteins
How does diffusion take place between the blood and the cells?
Through the tissue fluid
What happens to the forces as the blood moves through the capillaries towards the venous system?
The balance of forces changes
The hydrostatic pressure falls in the vessels as the fluid has moved out and blood moves through the capillaries towards the venous system. What is the new hydrostatic pressure? What is the oncotic pressure?
hydrostatic pressure= 2.3 KPa Oncotic pressure = -3.3 Kpa (it is now stronger than the hydrostatic pressure
As the oncotic pressure is stronger than the hydrostatic pressure what happens to the water?
It moves back into the capillaries by osmosis as it approaches the venous end of the capillaries
By the time the blood flows back into the veins how much of the tissue fluid is back in the blood vessels
90%
Draw a diagram showing the differences in hydrostatic pressure at arterial and venous end and how this results in movement into and out of the capillary
q
What happens to the 10% of tissue fluid that does not flow back into the capillaries?
It drains into a system of blindended tubes called lymph capillaries.
What is the tissue fluid in the lymph capillaries known as?
Lymph
Describe the composition of lymph
It is similar to plasma and tissue fluid but has less oxygen and fewer nutrients but does contain fatty acids.
How does the lymph contain fatty acids?
It is absorbed into the lymph from the villi of the small intestine
How do the lymph capillaries form larger vessels?
They join up to create larger vessels
How is the fluid transported in the lymph capillaries?
Via squeezing of the body muscles.
How is backflow prevented in the lymph?
Via one-way valves
Eventually the lymph returns to the blood via the…
right and left subclavian veins
Where are the subclavian veins located?
under the clavicle
What is another word for clavicle?
Collar bone
What are located along the lymph vessels?
The lymph nodes
Where are lymphocytes located?
In the lymph node (they are produced when necessary)
What do the lymphocytes produce?
Anti-bodies (which are then passed into the blood)
What does the lymphatic system play a major role in?
The defense mechanism of the body
What are enlarged lymph nodes a sign of?
That the body is fighting off an invading pathogen
Where are your lymph glands located in the body?
The neck, armpits, stomach and groin
What is a lymph gland?
A major lymph node
Osmosis video
What is the symbol for water potential?
ψ
What is the symbol for pressure potential?
ψp
What is the symbol for solute potential?
ψs
What does hypotonic mean?
An area of low solute concentration
What does hypertonic mean?
An area of high solute concentration
How do you calculate water potential?
Water potential = Pressure potential + Solute potential
What does ultrafiltration mean?
It refers to a medium that is fine enought to contain only small particle which leave behind the large molecules.
Crash course video on blood
