Lecture 9 Haematology II White Blood Cells Flashcards
State another name of a white blood cells
Leukocytes. Leukocytes refers to all the different types of WBCs.
Make sure you can identify the different types of WBCs from photographs
Check one-note for graphs after active recall.
What is the buffy coat
Contains mostly leukocytes (WBCs) and platelets
Which cells are contained in the buffy coat
Mainly platelets, leukocytes ( including neutrophils, lymphocytes, monocytes, basophils and Eosinphils)
List the functions of leukocytes
Defence of pathogens
Toxin and waste removal
Removal of damaged cells
Acts mainly outside the tissues
List the key features common of all white blood cells
All can migrate out of the bloodstream.
all capable of amoeboid movement.
all attracted to chemical stimuli
How are leukocytes (wbc’s) charactarized?
There are 2 categories of leukocytes.
1) Granulocytes
2) Agranulocytes
What does extravasation mean
This is the ability of white blood cells to migrate out of the blood stream
Which feature of Leukocytes is used as an indicator of disease
The number of leukocytes present in the blood.
What is the ratio of RBCs to platelets and white blood cells
700 RBC’s :40 platelets : 1 white blood cell.
Name the most common type of leukocyte
Neutrophils are the most common.
State the normal white blood cell count
Approx 4-11 x 10^9 white blood cells per litre of blood.
Describe the strucure of neutrophils
- most common
- 9-15 um in diameter
- distinctive nucleus with 2-5 lobes
- granular cytoplasm
Describe the functions of neutrophils
- First line of defense against bacterial infection.
- phagocytic
- mobile
- circulate in the blood for approx 10 hrs.
- major constituent of pus
Which of the white blood cells are phagocytic
Neutrophils, Eosinophils and Monocytes
What does it mean to be phagocytic
A cell capabe of ingesting/engulfing bacteria etc.
Describe the structural features of Eosinophils
10-12 micrometers in diameter.
Bi-lobular nucleus (2 lobed)
List some of the key functions of Eosinophils
- circulate in the blood for approx 8-12 hours
- survive 1-3 days
- release toxic compounds like NO and cytotoxic enzymes
- combat parasitic infections
- attack bacteria, protazoa and debris.
Which leukocyte only forms 2-4 % of the total white blood cells that circulate
Eosinophils.
Which type of Leukocyte is the least common
Basophils
Which type of leukocyte forms less than 1 percent of all circulating WBCs.
Basophils, these are the least common type of white blood cell.
Describe the structure of Basophils
- 8-10 micrometer in diameter
- Bi-lobed S shaped nucleus with large cytoplasmic granules.
- Granules are histamine and heparin.
Which type of stem cell gives rise to leukocytes
The common myeloid progenitor differentes to produce ….
The common leukocyte progenitor differentiates to produce lymphocytes?
Bi lobed, S shaped nucleus with cytoplasmic granules of Histamine and Heparin. Which type of WBC is being described here.
Basophils
What functions are Basophils involved in
Inflammatory response
Potentially a pre-cursor to mas cells..
Which type of WBC is the largest
Monocytes. They are the largest white blood cell.
State the structural features of monocytes
- Largest white blood cell
- Up to 20 micrometers in diameter.
- Large kidney/hores shoe shaped nucleus.
- Extensive cytoplasm.
How big are the monocytes
can be up to 20 micrometers in diameter
List the functions of monocytes
- Exhibit little function in the blood
- Migrate out of circulation after 3-4 days.
- Tissue macrophages
- have phagocytic properties.q
Lymphocyte structure
- Smallest white blood cell
- 6-15 micrometers in diameter
- lifespan is weeks to several years.
Lymphocyte functions
Central role in all immunological defense mechanisms
Circulates between various lymphoid tissues and all other tissues of body via blood and lymphatic vessels.
Provide some examples of lymphocytes
T cells
B cells
NK cells
What do T cells do
involved in cell mediated immunity
What do B cells do
Differentiate into plasma cells and secrete antibodies
What do NK cells do
responsible for immune surveillance - important in cancer prevention
