Science Biology Unit 8 (Lymphatic system) Year12 Flashcards
Define a Lymphocyte
White blood cell e.g. B-cells , T-cells , NK cells
Explain the functions of B , T and NK cells
B-cells - produce antibodies
T-cells - kill infected and cancerous cells
NK-cells - natural killer cells
Define antigens
Proteins on a the membrane of all cells
Explain functions of the lymphatic system
To transport lymph and also helps rid the body of toxins , waste and unwanted materials
Define lymph
A colourless , watery , bodily fluid consisting of mostly white blood cells
Define and locate lymph nodes
Removes cell waste and lymphatic fluid and storing lymphocytes , located in neck , armpits
Explain and locate the function of the spleen
Located between stomach and diaphragm
It filters out aging red blood cells , stores blood platelets , removes cellular debris by preforming phagocytosis
Define phagocytosis
The process in which invading microorganisms are engulfed and destroyed by phagocytes
Define a phagocyte
Cells that engulf foreign particles , bacteria and dead cells
Describe the phagocytosis
- Chemotaxis and adherence of microbe to phagocyte
- Ingestion of microbe
- Formation of phagosome
- Fusion of phagosome with a lysosome to form a phagosome
- Digestion of ingested microbe by enzyme
- Formation of residual body containing indigestible material
- Discharge of waste materials
Explain and locate the function of the thymus gland
Located behind your sternum and between your lungs
Active during youth , as time goes on it shrinks becomes less effective , protects the body from autoimmunity
