Blood

Question 1

Components of Blood

Answer 1

Blood is a fluid connective tissue that consists of cells within a matrix.

– Plasma: 55% of whole blood, consists of water, proteins, and other solutes (Serum is plasma minus proteins)

– Buffy coat: <1%, consists of platelets (Blood cell fragments), leukocytes, etc.

– Erythrocytes: 44% of whole blood, the red blood cells

Question 2

What are the functions of blood?

Answer 2

1. Transportation
   -O2 from lungs to body cells
   -CO2 and metabolic waste from cells
   -Nutrients
   -Hormones
2. Regulation
   -Maintain body temperature, pH, and fluid volume
3. Protection
   -Leucocytes help against infection
   -Platelets and plasma proteins form blood clots, which protects against blood loss

Question 3

What are the main proteins in the plasma?

Answer 3

-Albumin: Prevents water from diffusion out of blood vessels by osmosis, carrier molecules

-Globulins: Antibodies and blood proteins- transport lipids, iron, and copper

-Fibrinogen: Clotting proteins

-Regulatory proteins: Proenzymes, enzymes

Question 4

What are the solutes in the blood plasma?

Answer 4

Over 100 dissolved solids
– Ions
Na+ and Cl–

– Nutrients
Sugars, amino acids, lipids

– Gases
Oxygen, carbon dioxide, nitrogen

– Vitamins

– Wastes
Carbon dioxide, urea, ammonia

Question 5

What are the three components of formed elements?

Answer 5

1. Red blood cells
   Erythrocytes
2. White blood cells
   Leukocytes
3. Platelets

Question 6

Describe erythrocytes

Answer 6

-No nucleus or organelles in humans

-Bag of hemoglobin bound by plasma membrane, 97% hemoglobin

-Biconcave structure, helps with loading & unloading gasses

-Form in red bone marrow

-Functions: Mostly O2 transport, hemoglobin binds easily and reversibly, single erythrocyte has 250 million hemoglobin molecules, each has 4 heme groups, 1 erythrocyte binds 1 billion O2 molecules, small amount of CO2

– Lifespan ~ 120 days, most are destroyed by macrophages in the spleen, some components are recycled, others excreted

Disorders:
– Anemias
* Blood has low oxygen carrying capacity
– Not enough red blood cells
– Decrease in hemoglobin
– Abnormal hemoglobin
» Ex: Sickle cells

– Polycythemia
* Abnormal excess of erythrocytes
Erythrocytes

Question 7

Leukocytes

Answer 7

-Complete cells
-Less than 1% of all blood cells
-Defense against disease
-Can leave capillaries and move
through tissue with amoeboid
motion

Two categories:
1. Granulocytes- Cytoplasmic granules
2. Agranulocytes

Question 8

What are the three kinds of granulocytes?

Answer 8

1. Neutrophils
   > 50% of leukocytes
   Multilobed nucleus
   Chemically attracted to sites of inflammation
   Active phagocytes of bacteria and some fungi
2. Eosinophils
   1-4% of leukocytes
   Bilobed with large granules in cytoplasm
   Kill parasitic worms with enzymes in lysosomes
3. Basophils
   0.5% (rarest)
   Large s-shaped nucleus
   Releases histamine

Question 9

What are the two kinds of agranulocytes?

Answer 9

1. Monocytes
   Largest leukocyte
   U-shaped nucleus
   Acts as a macrophage of viruses
   and bacteria
2. Lymphocytes
   Second most common leukocyte
   About the size of an erythrocyte
   Nucleus spherical or indented
   Responsible for immunity

Question 10

Platelets

Answer 10

Cell fragments
Contain chemicals that aid in clotting
Degenerate in about 10 days
Megakaryocytes ruptures to form platelets