Chapter 19 - Blood Flashcards
Blood
A fluid filled connective tissue which is about 8% of our body weight.
What is the average pH of blood?
7.35 - 7.45 (neutral - similar to water)
In litres, what is the volume of blood needed for adult males and females?
Males: 5-6 litres
Females: 4-5 litres
What does the darkness of blood signify?
Bright red blood = oxygen rich
Dark red blood = oxygen poor
What are the 3 functions of blood?
1. Transport oxygen and nutrients to cells, and wastes away from cells.
2. Regulate body temp, pH of tissues, water content in tissues.
3. Protect against blood loss by clotting, and against infection by WBC’s.
What is blood composed of?
- Plasma - (55%) a watery fluid that contains dissolved substances.
- Formed elements - (45%) red blood cells, white blood cells, platelets
What is the transport pathway of blood?
- Lungs and gut give 02 and nutrients
- Those go into the blood
- Interstitial fluid
- Body cells
- CO2 and waste
- Interstitial fluid
- Blood
- Kidneys, skin, lungs
Blood plasma
The fluid portion of blood composed of 90% water and 10% solutes.
Solutes include: electrolytes, nutrients, enzymes, hormones, gases, metabolic wastes, and plasma proteins produced by the liver
What are the names of the 3 main plasma proteins and how much do they account for in the plasma?
- Albumin - 54% of plasma proteins
- Globulins - 38% of plasma proteins
- Fibrinogens - 7% of plasma proteins
These account for 8% of the 10% of solutes in plasma
Albumin
A plasma protein which:
- helps with the maintenance of osmotic pressure (keeping water in blood plasma)
- acts as a buffer to maintain pH
- it is a carrier molecule of fatty acids and steroid hormones
Globulins
A plasma protein with 2 subdivisions:
- Alpha and beta globulins - transport iron, metals, lipids, fat-soluble vitamins.
- Immunoglobulins - antibodies which are released by plasma cells during immune response.
Fibrinogen
A plasma protein which is a precursor of fibrin and helps with blood clotting
Red blood cells (RBC’s)
Function to transport respiratory gases (O2, CO2)
Each RBC contains about 250mil molecules of hemoglobin.
Each hemoglobin molecule is made of 4 polypeptide chains, and an iron containing “heme” pigment bound to each of the 4 chains.
Why do red blood cells contain no nucleus or organelles? How do they generate ATP?
Mature RBC’s pinch off their nucleus and other organelles to increase the surface area of oxygen transport.
Lack of a mitochondria means they must generate ATP anaerobically so they don’t use the oxygen they are transporting to the rest of the body.
What is the average life span of a red blood cells
About 120 days