what are the primary lymph organs
o Thymus (sits inferior to butterfly shaped thyroid gland) o Bone marrow
what are primary lymph organs
• Organs where immature lymphocytes acquire the receptors to recognise antigens
2 parts of the thymus
cortex + medulla
describe the thyme cortex
• Cortex of thymus pack with immature and maturing T cells (thymocytes)
• Approx same size as erythrocyte
o But has nucleus, granular
describe the thyme medulla
form groups of keratinised epithelial cells and have debris fragments in lumen
difference of thymus corposucles from blood vessels
* Different items inside lumen= not erythrocytes
what occurs in bone marrow
* Site of B lymphocyte maturation
how is a bone marrow smear different to blood smear
what are secondary lymphoid organs
• Organs where lymphocytes are activated in response to antigens
what are the secondary lymphoid organs
• Lymph nodes
o Ilium > cecum= ileocecal valve = size change > slows chyme waiting to go into LI
• Spleen
• Mucosa-associated lymphoid tissues (MALT) in tonsils and intestine
what re the palpable lymph nodes
* Deep cervical lymph nodes surrounding the internal jugular vein.
histological structure of lymph node
• Adipose surrounding (white)
• Thick capsule surrounding
• White sub captual sinus (blood comes in)
• Slightly active as have secondary folicules
Group of lymphs already tagged antigen and replicating
features of medullar sinus (lymphatic channels)
where is spleen located
left hypochondirum
blood vessels in and out of spleen
* Splenic vein drains splenic blood to liver.
role of spleen
how to find spleen
• X ray, deep near ribs, next to right kidney
what is the red and white pulp in spleen
White pulp looks purple on micrograph (as full of lymphocytes)
why is there a gap on top of slpleen
where artery and vein is
describe activated lymph
Dark ring (mantle zone= b cells) with lighter centre (germinal centre= b cell activation, expansion)
what are PALS
Pariarteriolar Lymphoid Sheath
• Arteriolessurrounded with large numbers of lymphocytes and macro
• Heavy density
• = first line of defense as what seeps outs arteriole attacksby dense
TYPES OF malt (Mucosal associated lymphoid tissue )
tonsils, •
GALT= Aggregated lymphoid nodules of ileum + Aggregated lymphoid nodules of appendix
difference of spleen and tonsil
o Lot of lymphocytes (purple)= angry secondary follicles
o Little blood
o Different shape
• Clefts allows entry and trap > attack
ilium vs appedix
• Entire lumen covered in lymphoid tissue (different to ilium)