Unit 1 - The Blood (Midterm #1) Flashcards
(109 cards)
What are the 5 functions of blood?
- Transport (gases, nutrients, wastes, etc)
- Stabilizing pH and electrolyte composition
- Restricting fluid loss (through clotting)
- Defending body against toxins and pathogens (WBCs)
- Stabilizing body temperature
Does blood have a higher or lower viscosity than water?
Higher viscosity than water
- it is thicker, moves more slowly
What is the main determinant for blood viscosity?
The number of red blood cells in the blood
What happens if the blood has a high osmolarity?
Big dissolved particles in the blood cannot leave the blood vessel, fluid will flow INTO the blood vessels to try to dilute the blood concentration.
- Results in high blood pressure
What happens if the blood has a low osmolarity?
Big dissolved particles in the blood cannot leave the blood vessel, fluid will flow OUT of the blood vessels to try to dilute the interstitial spaces and into the tissues
- Results in low blood pressure
What could result if there is a significant drop in blood osmolarity?
Edema!
- fluid enters the tissues, results in swelling
Define Hypovolemia.
Low blood volume
(
Define Normovolemia.
Normal blood volume
4 - 6 litres
Define Hypervolemia.
Excessive blood volume
> 6 litres
What happens to blood pressure if the patient is hypovolemic? Hypervolemic?
Hypovolemic = low blood pressure (excess loss of fluid), tissues might not be well perfused Hypervolemic = high blood pressure (too much fluid)
Why might a patient have more or less blood than is considered “normal”?
Blood volume varies with body weight
- a large patient will have a higher blood volume
- a small patient will have a smaller blood volume
What are the formed elements of blood?
- Cells
2. Cell fragments
What does plasma consist of?
- Water
- Electrolytes
- Proteins
- Other dissolved and suspended particles
What is the ratio of whole blood to plasma?
Approx 55% plasma
Approx 45% whole blood
What makes up 92% of plasma?
Water!
How is blood plasma different from interstitial fluid?
- It has a higher amount of dissolved oxygen in it
- It has a large number of dissolved proteins in it
How is the ration of whole blood:plasma different in men and women?
Men have less plasma relative to whole blood (higher oxygen carrying capacity)
Women have more plasma relative to whole blood
Why are pH changes in plasma lower than in interstitial fluid?
Because of the buffering capability of the proteins in the blood
What are the 4 different kinds of proteins found in the blood plasma?
- Albumins
- Globulins
- Fibrinogen
- Regulatory proteins
What is the most prevalent protein found in blood plasma?
Albumins (60%)
- Globulins (35%)
- Fibrinogen (4%)
What is the function of Albumins?
- Contributes to oncotic pressure (ability to draw water INTO the bloodstream)
- Attaches to lipids to form lipoproteins
What is the function of Globulins?
Immunoglobulins attack foreign proteins
What is the function of Fibrinogen?
Important in blood clotting
What is leftover if you remove fibrinogen from plasma?
Serum