Structure and Function (Strom)

Question 1

What are the properties of Eosin Y?

Answer 1

• Aromatic/acidic
• Soluble in ethanol, NOT in water
• Stains hydrophobic basic macromolecules (ex. hemoglobin)

Question 2

How does eosin Y stain RBCs?

Answer 2

Eosin Y is aromatic and negatively charged (acidic). Heme is aromatic and has a positively charged ion (base) in it’s center that “sticks” to the stain

Question 3

What are the properties of methylene blue?

Answer 3

• Aromatic/basic
• Soluble in water OR methanol
• Stains hydrophobic acidic macromolecules (nucleic acids, some proteins)

Question 4

Knowing the count of what type of blood cell is essential in evaluating any infectious disease?

Answer 4

neutrophil

Question 5

What does the term “amphiphilic” mean? What cells have this characteristic?

Answer 5

Pale blue cytoplasm (few cytoplasmic granules) seen in monocytes and lymphocytes

Question 6

List the 7 RBC “design” requirements.

Answer 6

Flexible shape
Durable membrane
Maximum Hgb/O2 carrying capacity
Offset osmotic pressure
Anti-oxidant system
Energy supply
Ability to tune down complement fixation

Question 7

Is the RBC membrane skeleton located on the inside or outside of the cell membrane?

Answer 7

inside

Question 8

What are the two major proteins involved with maintaining the structural integrity of RBCs?

Answer 8

ankyrin and spectrin

Question 9

Why are minor changes in the globin amino acid sequence or oxidative damage bad for RBCs?

Answer 9

Hemoglobin is packed into RBCs at the highest feasible concentration, which means it is just barely below that at which it will precipitate, so even slight changes can cause it to precipitate

Question 10

How do RBCs manage the osmotic pressure that occurs due to the high amount of hemoglobin inside?

Answer 10

they pump sodium ions OUT of the cell using a Na+/K+ ATPase

Question 11

What happens to RBCs with no ATP?

Answer 11

they swell and burst (water flows in along concentration gradient)

Question 12

What is Methemoglobin?

Answer 12

RBCs that have an oxidized form of iron (Fe3+) that cannot carry oxygen

Question 13

What is the pathway called that generates NADPH to return methemoglobin (with clumps of oxidized hemoglobin) to the functionally active Fe2+ state?

Answer 13

hexose monophosphate (pentose phosphate) pathway

Question 14

The hexose monophosphate shunt pathway relies on what “middle man” between H2O2 and NADPH?

Answer 14

glutathione

Question 15

True or flase: RBCs use mitochondria for energy?

Answer 15

FALSE!

Question 16

RBCs contain what surface protein to “tune down” complement fixation?

Answer 16

DAF (decay accelerating factor)

Question 17

What is hypochromia?

Answer 17

refers to lack of color (lack of hemoglobin as stained on a slide by eosin)

Question 18

What word refers to abnormal red cell shapes?

Answer 18

poikilocytosis