Blood

Question 1

Functions of Blood

Answer 1

Transport of gases, nutrients, hormones and waste products.
Regulation of pH and electrolyte composition of interstitial fluids.
Restriction of fluid loss due to damage.
Defense against pathogens and toxins.
Temperature homeostasis.

Question 2

Plasma

Answer 2

55% of blood volume
92% of plasma is water
7% of plasma consists of dissolved plasma proteins (albumins, globulins and fibrinogen)
1% of plasma is a mix of ions, nutrients and waste products.

Question 3

Globulins

Answer 3

35% of plasma proteins are globulins.
Include antibodies and transport proteins.
Antibodies aid in immunity
Transport proteins bind to substances to prevent their loss at the kidneys.

Question 4

Albumins

Answer 4

60% of plasma proteins are

Their major function is to maintain osmotic pressure of the plasma.

Question 5

Fibrinogen

Answer 5

~ 5% of plasma protein

Functions in blood clotting.

Question 6

Formed Elements

Answer 6

Red Blood Cells (RBCs)
White Blood Cells (WBCs)
Platelets

Question 7

RBCs or Erythrocytes

Answer 7

Contain pigment hemoglobin to bind and transport O2 and CO2.
Most abundant of the formed elements.
RBC structure gives them a large SA to volume ratio which is ideal for maximizing diffusion rates.
RBC structure makes them flexible which allows for passage through narrow capillaries.
Mature RBCs are anucleated and loose most of their other organelles as well.

Question 8

Erythropoiesis

Answer 8

Occurs in Red Bone Marrow.
Hemoblasts in red marrow produce myeloid stem cells which produce RBCs (erythrocytes).
Erythroblasts are immature RBCs that produce hemoglobin (stage lasts 4 days).
Nucleus is shed and cell becomes reticulocyte (reticulocyes enter circulation after 2 more days in marrow).
After 24 hours reticulocyte becomes mature erythrocyte (RBC).

Question 9

EPO (erythropoietin)

Answer 9

Hormone that stimulates erythropoiesis.
Its release is stimulated by low O2 concentrations called hypoxia.
Released during anemia (because blood flow to kidneys declines) and low O2 in air or the lungs (due to environment or disease).
Results in increased amounts of erythroblasts and myeloid stem cells.
Results in faster RBC maturation by increasing hemoglobin synthesis.

Question 10

EPO, Blood Doping and Athletes

Answer 10

Many athletes use synthetic EPO to increase the amount of O2 available for exercise.
The same can be achieved through “Blood Doping”.
Synthetic hemoglobin can also be injected to increase O2 capabilities.
What are the potential benefits and costs of such practices?
If EPO occurs in the body naturally and Doping involves a persons own blood how do you test for it?
Do tests work?

Question 11

Blood Types

Answer 11

A, B, O, AB, Rh+, Rh-

Named based on their surface antigens and the presence or absence of Rh factor.

Question 12

Blood Clotting

Answer 12

Occurs when a blood vessel has been damaged.
Clotting factors are converted to active enzymes that direct essential reactions.
Extrinsic and Intrinsic pathways respond to damage usually within seconds.
Platelets are vital to the process of blood clotting (via the intrinsic pathway) and are immediately rushed to and area of damage.