Blood & RBCs

Question 1

What is Blood & the Characteristics of Blood (5)

Answer 1

1) ONLY Liquid Connective Tissue in the body
2) 8% of total body weight
3) Consistency= thick, viscous (higher gravity than distilled water)
4) Color= ranges from Scarlet red (oxygen-rich) to dark red (oxygen poor)

Question 2

Normal pH, Volume, & Temp of Blood

Answer 2

• pH= 7.4 (ranges from 7.35-7.45)
• Volume= Men= 5-6 L (1.5 gal) & Women= 4-5 L (1.2 gal)
• Temp= 38 degrees Celsius (aka 100.4 degrees F)

Question 3

Blood functions (3)

Answer 3

1) Transportation (gases, nutrients, hormones, etc.)
2) Regulation (of pH, temp, water balance & electorlyte balance)
3) Protection (via WBCs, antibodies, & blood clotting)

Question 4

Components of Blood & their blood volume %

Answer 4

Blood Plasma (55%) & Formed elements (45)

Question 5

Characteristics & Components of Blood Plasma

Answer 5

• Fluid component of blood, slightly yellow
  -90% water & 10% solutes

Question 6

What makes up the solutes found in blood plasma? (5)

Answer 6

1) Electrolytes (most abundant)–> Na, K, Ca, etc.
2) Plasma proteins (AGF)
3) Nutrients (glucose, amino acids, glycerol, etc)
4) Respiratory gases (O2 & CO2)
5) Hormones

Question 7

What plasma proteins are found in the solutes of blood plasma? (3)

Answer 7

• found only in blood plasma & synthesized in the liver
  1) Albumin (60%
  2) Globulin (36%)
  3) Fibrinogen (4%)

Question 8

What are the formed elements in blood and how many are there?

Answer 8

1) Erythrocytes (RBCs) = 4.2-5.8 million
2) Leukocytes (WBCs) = 5,000-9,000
3) Thrombocytes (Platelets) = 250,000-400,000

Question 9

Hematopoiesis & Pluripotent Hematopoietic Stem Cells

Answer 9

• Blood cell production
• located in Red Bone Marrow, where all blood cells develop from

Question 10

Characteristics of Erythrocytes (RBCs) (6)

Answer 10

1) 99% of all formed elements (blood cells) in circulation
2) Major contributor to viscosity
3) Biconcave, disc shaped
4) Anucleate= no nucleus
5) Amniotic= don’t divide
6) Flexible cell membranes with no organelles
7) Composed of mostly Hemoglobin

Question 11

Why do RBCs not have mitochondria?

Answer 11

NO mitochondria = NO aerobic respiration (allows them to conserve all the O2 they carry so ALL their O2 is delivered to other cells)

Question 12

Hemoglobin (3)

Answer 12

• 4 iron (heme) groups & 1 protein (globin) group
• Makes up about 1/3 of the weight & 97% of an RBC
• Gives RBCs red color

Question 13

Hemocrit

Answer 13

% of total blood volume occupied by RBCs

Question 14

What is the average number of RBCs & Hematocrit for men and women?

Answer 14

Men= 5.4 million per uL & 47%
Women= 4.8 million per uL & 42%

Question 15

Hypoxia vs. Hyperoxia

Answer 15

-Hypoxia= not enough oxygen being delivered to tissue
-Hyperoxia= too much oxygen in the body which causes blood to become too viscous and clog small blood vessels

Question 16

Erythropoiesis & rate & causes (3)

Answer 16

• RBC production
• produced at a rate of 2 million per second
  1) Reduced number of RBCs
  2) Insufficient Hemoglobin
  3) Reduced availability of oxygen

Question 17

Steps of Erythropoiesis (5)

Answer 17

1) Kidneys release REF enzyme into bloodstream
2) REF converts plasma proteins into Erythropoietin (hormone)
3) Erythropoietin circulates to red bone marrow & causes Proerythroblasts to begin RBC developmental process
4) Towards end of the development Reticulocyte develops (RBC precursor)
5) Reticulocyte enters bloodstream and develops into mature RBC in 1- 2 days

Question 18

Stages of Erythropoiesis (5)

Answer 18

1) Kidneys –>REF enzyme
2) REF –> plasma proteins –> Erythropoietin
3) Erythropoietin –> Red bone marrow
4) PROerythroBLASTS –> Reticulocyte
5) Reticulocyte –> bloodstream = RBC in 1-2 days

Question 19

REF

Answer 19

Renal Erythropoietic Factor
- released by Kidneys whenever low oxygen levels are detected
- Initiates Erythopoiesis

Question 20

Erythropoietin

Answer 20

-Hormone that is slowly released from the liver (under normal conditions)
-During Erythropoiesis, converted from plasma proteins by REF to circulate into red bone marrow & causes preoerythroblasts to begin development of RBCs

Question 21

Reticulocyte

Answer 21

• RBC precursor
  -Anucleate (no nucleus)
• Contains significant amounts of hemoglobin & several organelles
• Develop into mature Erythrocytes in 1-2 days

Question 22

Reticulocyte Count

Answer 22

• Measures the rate of Erythropoiesis
• Number of retifulocytes in the bloodstream used as an indicator of the response of red bone marros to erythropoietin
• Normal count= 0.5-1.5% of all RBCs in a blood sample

Question 23

How long do RBCs live in the bloodstream? Where are the removed/broken down?

Answer 23

• 120 days
• Old worn-out RBCs removed from by bloodstream and destroyed in the spleen & liver

Question 24

How is Hemoglobin from old RBCs broken down?

Answer 24

1) Heme & Globin components are separated –> Globin broken down into amino acids (to make other proteins) & iron removed from heme
2) Iron from heme transferred to iron-storing proteins (Ferritin & Hemosiderin)
3) Iron proteins transported to red bone marrow from hemoglobin synthesis
4) Non-Iron portion of heme converted into Bilirubin

Question 25

Ferritin & Hemosiderin

Answer 25

Iron-storing proteins that transport the iron carrying heme portion of hemoglobin from old RBCs to red bone marrow to be used for hemoglobin synthesis

Question 26

Bilirubin

Answer 26

yellow-orange pigmented non-iron portion of heme transported from old RBCs into the liver where it’s secreted into bile

Question 27

Erythrocyte Disorders

Answer 27

• caused by either blood loss, not enough RBCs, or too many RBCs being destroyed
• Anemia –> ability of blood to carry oxygen is reduced.

Question 28

Hemorrhagic Anemia

Answer 28

• Anemia due to blood loss (EX: heavy period)
  -Acute= rapid blood loss (EX: stab wound)
• Chronic= slight, persistent blood loss (EX: bleeding ulcer)

Question 29

Anemia due to decreased RBC or Hemoglobin production (4)

Answer 29

1) Aplastic Anemia- damage to red bone marrow
2) Iron-deficiency Anemia- reduced iron causes reduced hemoglobin production
3) Pernicious Anemia- lack of parietal stomach cells causes insufficient RBC production
4) Renal Anemia

Question 30

Hemolytic Anemia (2 types)

Answer 30

• excessive loss of RBCs via hemolysis
  1) Thalassemias
  2) Sickle-Cell Anemia