Blood Flashcards
What are the three components of blood? What are they more commonly known as?
- Erythrocytes: Red blood cells
- Leucocytes: White blood cells
- Platelets
What is the pH of blood?
7.35-7.45
What are the two colors blood can be? What are the conditions for blood to be these colors?
Oxygenated blood is scarlet or bright red, and deoxygenated blood is a very dark red or even blue.
How much blood is in average human bodies?
Roughly 8 percent of body weight, 4-5L in females and 5-6L in males.
What are the three main subcategories of blood function?
Distribution, regulation, and protection
What does blood distribute?
- Oxygen and nutrients
- Metabolic Wastes
- Hormones
What 3 things do blood regulate?
- Temperature (distribution, dissipation, conservation)
- pH in body tissues (plasma proteins, bicarbonate reserves)
- Adequate fluid volume
What does blood protect against?
- Blood loss (plasma and platelets)
- Infection (Antibodies, compliment, WBCs)
What is the blood pH buffer reaction?
CO2+ H20 <-> C2HCO3 <-> HCO3^- + H^+
What is the most dense part of blood (bottom when spun in the centrifuge)? What percentage of the blood does it make up?
The Erythrocytes make up roughly 45% of the blood.
What is the most least dense part of blood (top when spun in the centrifuge)? What percentage of the blood does it make up?
Plasma makes up roughly 55% of the blood.
What is blood plasma?
It is 90 percent water with solutes.
What are plasma proteins?
They are functional proteins that are in blood.
What is the most common plasma protein?
Albumin (60% of plasma)
Where are plasma proteins produced? What is the exception to the rule?
They are produced in the liver, however gamma globulins are antibodies and are produced by cells of the immune system.
What are the roles of albumin?
- It is a carrier of molecules
- It is a buffer
- It is an osmotic protein
What is the major osmotic ion? What charge does it have?
Na+
What are the only complete cells in the blood? Why?
Leukocytes have nuclei as opposed to erythrocytes and platelets.
What is the size and shape of a red blood cell?
It is a biconcave disc about 7.5 micrometers in diameter.
What is the composition of an erythrocyte?
It is a “bag of hemoglobin” with other proteins to maintain permeable membrane and cell shape
What does spectrin do?
It allows erythrocytes to change their shape and squeeze through narrow capillaries/reassume normal shape.
What are the three special characteristics of erythrocytes that optimize function?
- Small size and shape gives a large SA to V ratio.
- It is mostly hemoglobin (97% of non-fluid composition)
- Generate ATP anaerobically, do not use oxygen to meet their own needs.
Do red blood cells transport CO2?
Yes approximately 20 percent.
How are rate of blood flow and RBC count related?
They have an inverse relationship
What is the composition of a globin protein?
It is made of 4 polypeptide chains, two alphas (lighter) and two betas (darker).
What are the meanings of the two words that make up hemoglobin?
Heme = red pigment
Globin = protein
What atom is in the middle of each heme group? Why is it imporant?
Iron can reversible bind to oxygen. (Can hold onto but can also release into the surrounding area)
Why is hemoglobin contained in erythrocytes?
There is a lot of it, so the packaging of hemoglobin keeps it from fragmenting and getting lost, and also keeps it from directly affecting blood osmotic pressure and viscosity.
What do we call hemoglobin molecules with and without oxygen?
OxyHb and deoxyHb
What molecules bind where on a hemoglobin molecule?
Oxygen binds to the heme group and carbon dioxide binds to the globin protein
What do we call the carbon dioxide bound to globin?
carbaminohemoglobin
What is the starting point cell for the production of blood components?
Hematopoietic stem cells, or hemocytoblasts
Define hematopoeisis
It is the general term for the production of formed elements in the red bone marrow
What is the term for the hematopoiesis specifically of erythrocytes?
Erythropoiesis.
What is the name of the committed cell in the erythropoiesis process?
The proerythroblast
Simple describe the developmental pathway of erythrocytes.
The proerythroblasts fill with hemoglobin and then eject the nucleus
What is the name of the entity at the end step of erythropoiesis that is essentially an erythrocyte that has not moved out into the circulatory system?
A reticulocyte
What is the structural difference between an erythrocyte and a reticulocyte?
A reticulocyte has some additional protein synthetic machinery
How long does erythropoiesis take?
Around 15 days
What does a reticulocyte count indicate? What is a healthy range?
A reticulocyte count of roughly 1-2 percent of erythrocytes indicates a solid ability of the bone marrow to produce new erythrocytes.
What are the two abnormalities associated with erythropoiesis.
Anemia = too few RBCs
Polycythemia = too many RBCs
What is a healthy production rate of RBCs?
More than 2 million/second
What is EPO?
Erythropoietin is a glycoprotein hormone responsible for a higher RBC count.
Where is the primary site of EPO production?
The kidneys
When is EPO release stimulated?
Hypoxic conditions eg.
1. hemorrhage/RBC destruction
2. High altitude
3. Increased Demand
How long after EPO production does RBC count rise?
1-2 days
What is a risk of EPO abuse in athletes?
Increased blood viscosity and dehydration can cause stroke, clotting, or heart failure
What is the effect of testosterone on EPO production?
It is stimulating
Why would women have a lower hematocrit than men?
- No testosterone
- Lose blood through menstruation
What are the two dietary requirements for erythropoiesis?
Iron and B vitamins