Intro to structure and function of blood

Question 1

What are the 4 parts of the blood?

Answer 1

Red blood cells (44%)
White blood cells (<1%)
Platelets (<1%)
Plasma (55%)

Question 2

What is the structure of red blood cells (Erythrocytes)?

Answer 2

Biconcave disc
No nucleus
Does not contain DNA, RNA or mitochondria

Question 3

What is the major constituent of red blood cells?

Answer 3

The protein haemoglobin (Hb). It forms about 1/3 of the rbc.

Question 4

Describe the structure of Hb.

Answer 4

A protein tetramer made up of 4 polypeptide chains; 2 alpha globin chains and 2 beta globin chains. Each globin chain carries a heme molecule in the centre.

Question 5

What is the function of Hb?

Answer 5

It binds irreversibly to oxygen at the lungs and carries it around the body to tissues.

Question 6

How does oxygen bind to the Hb?

Answer 6

Each heme molecule on each polypeptide chain holds a ferrous (Fe++) iron atom. Oxygen irreversibly binds to this iron atom and is carried from the lungs to tissues.

Question 7

Explain the difference between new rbc and mature rbc.

Answer 7

New red blood cells have RNA, DNA, mitochondria and a nucleus.
Mature red blood cells don’t have any of these and only have haemoglobin.

Question 8

What is the average lifespan of RBC?

Answer 8

120 days - but if it is damaged or something is wrong with it then it will be removed before the 120 days.

Question 9

What are white blood cells also known as?

Answer 9

Leukocytes

Question 10

What colour are lymphocytes?

Answer 10

Colourless

Question 11

What are the different classifications?

Answer 11

Granulocytes - prominent cytoplasmic granule
Agranulocytes - lack visible cytoplasmic granules

Question 12

5 Types of WBC

Answer 12

Neutrophils
Lymphocytes
Monocytes
Eosinophils
Basophil

Question 13

What are the two most common types of WBC?

Answer 13

Neutrophils and Lymphocytes

Question 14

What is the least common type of WBC?

Answer 14

Basophil

Question 15

Features of neutrophils

Answer 15

(40-60% of wbc)
Polymorphonuclear: irregular, multi-lobed nucleus (>3 lobes)
Weakly staining cytoplasm granules using normal dye.

Question 16

Features of eosinophil

Answer 16

(1-4% of wbc)
Stains acidic; cytoplasmic granules stain red with eosin
Looks reddish in colour
Multi-lobed nucleus

Question 17

Features of basophil

Answer 17

(<1% of wbc)
Cytoplasmic granules stain blue/purple with basic dye.
Since the nucleus is a similar colour to the staining of the granules, it can be difficult to see the nucleus of the granules.
It has multi-lobes of nucleus.

Question 18

What happens if you dye Basophil with haemotoxylin?

Answer 18

If you dye with haematoxylin, when the granules stain blue/purple, it starts to mask the nucleus or the purple granules.

Question 19

Features of lymphocytes

Answer 19

25% of wbc
They are part of the immune system
2 types - T- & B-lymphocytes