Blood Cells - Functions Of Leucocytes Flashcards Preview

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Flashcards in Blood Cells - Functions Of Leucocytes Deck (19):
1

Where are blood cells produced?

In haematopoietic tissues such as bone marrow

2

What percentage of the world have iron deficiency anaemia?

30%

3

What are newly formed erythrocytes called?

Reticulocytes

4

Why can reticulocytes be stained by specific dyes, and what are these dyes called?

They can be stained because they contain small amounts of RNA.

Cresyl violet
Methylene blue

5

Describe the clinical significance of the reticulocyte count?

The lifespan of a reticulocyte is short and therefore it gives information on the activity of the bone marrow.

Increased reticulocyte count indicates that erythrocytes production has increased.

6

Name different types of leucocytes.

+ Granulocytes
+ Monocytes
+ Lymphocytes
+ Neutrophils
+ Eosinophils
+ Basophils

7

What are the features of the bacterium Streptococcus pneumoniae?

+ It's one cause of pneumonia

+ 5% mortality rate

+ In 20% patients, the bacterium spreads to the blood

+ If it spreads then mortality is 20%

8

How do you restrict infection to the lungs?

+ Induce chemotaxis of neutrophils - confines pathogen to local site

9

What is released in order to prevent clotting?

Heparin

10

What is released during an allergic reaction?

Histamine

11

What is the average life span of a red blood cell?

120 days

12

What is the role of mast cells and basophils in the immune system?

Bind onto antibodies in bloodstream via Fc receptors on their surface - IgE is the antibody involved in allergic responses.

13

What 3 active agents are typically released in basophil and mast cells?

+ Histamine

+ ECF-A: an eosinophil chemotactic factor for anaphylaxis

+ SRS-A: a slow reactive substance of anaphylaxis

14

What are features of monocytes?

+ Monocytes/macrophages are produced in the bone marrow

+ In the bloodstream they are called monocytes

+ Migrate into the blood then local tissue, where they become fixed tissue phagocytes

+ Highly phagocytic

15

What are the two different types of Monocytes?

+ M1 macrophage: involved in disruptive processes. Pro-inflammatory


+ M2 macrophage: pro-resolution

16

Describe features of a lymphocyte.

+ Small when circulating in the bloodstream;resting stage

+ Immune response initiated; gets much bigger; transforms to a lymphoblast and proliferates

17

What are the two main types of lymphocytes?

+ B-cell: produces plasma cells (humoral response). Antibody producing cells.

+ T-cells: cytotoxic killer cells (cell-mediated response). Can kill other cells if infected with a virus. Involved in graft rejection.

18

What is the role of a lymphocyte?

To eliminate the antigen, either by releasing antibodies (B cells), cytotoxic granules (T cells) or by signaling to other cells of the immune system (helper T cells)

19

What is the role of a monocyte?

+ Phagocytosis
+ Antigen presentation (capturing antigens)
+ Cytokine production