Lymphatic system histology Flashcards
What are the three functions of the lymphatic system?
- Drain Excess Interstitial Fluid and return it to blood stream to help
maintain normal blood volume - Immune Response – produce, maintain, and distribute lymphocytes
- Provide an Alternative Transportation Route for Hormones, Nutrients, and Waste Products
What do B cells do?
They produce and secrete antibodies along with their derivative cell- humoral immunity- these make up 20-30% of circulating lymphocytes
What do T cells do?
After differentiation in the thymus they attach to and destroy cells- cell mediated immunity- these make up 60-80% of circulating lymphocytes
What do natural killer cells do?
They kill transformed cells- these make up 5-10% of circulating lymphcytes
Does diffuse lymphatic tissue have a capsule?
No
What is diffuse lymphatic tissue made of?
It is the accumulation of lymphocytes in the lamina propria of the alimentary canal, as well as respiratory, urinary, and reproductive tracts
In diffuse lymphatic tissue, will you find plasma cells or eosinophils?
Yes
What are lymphatic nodules and where are they found?
Accumulations of lymphocytes found in the wall of alimentary canal, as well as respiratory urinary and reproductive tracts
Do lymphatic nodules have a capsule? Are they sharply defined?
No
Yes
Will you see red blood cells in lymph?
No
What are the two types of lymphatic nodules? How are they differentiated?
Primary nodules- the aggregation of primarily small lymphocytes
Secondary nodules- have germinal center (with follicular dendritic cells present) and mantle zone
T/F Normally lymphatic nodules are found uniformly dispersed and by themselves?
False- randomly dispersed by themselves
T/F In certain locations of the alimentary canal, lymphatic nodules are grouped together?
True
What are two examples of lymphatic nodules?
Tonsils- create a ring around the entrance to the oropharynx and the nasopharynx
Peyers patches- found in the ileum
MALT stands for?
GALT stands for?
BALT stands for?
Mucous-associated lymphatic tissue
Gut-associated lymphatic tissue
Bronchus-associated lymphatic tissue
Diffuse lymphatic tissue and nodules are named for _____.
The region or organ in which they apear
What is a lymph node?
A capsuled organ along the pathway of the lymphatic vessels
What does a lymph node do?
Acts as a filtering system
Lamina propria is found in conjunction with which type of membrane?
Mucous
For lymph nodes, what are the four cells of the reticular meshwork?
Reticular cells
Dendritic cells
Macrophages
Follicular dendritic cells
What is the flow of lymph through the lymph node?
Afferent lymph vessel–subcapsular (cortical) sinus–Trabecular sinus–Medullary sinus–Efferent lymph vessel
The thymus is the site of ______ _____ _____, a process through which T cells mature and differentiate into immunocompetent T cells.
thymic cell education
What is the function of the spleen?
It filters and monitors the blood immunologically just as the lymph nodes monitor lymph
The spleen consists of two parts- what are they?
Red pulp
White pulp
What is the red pulp of the spleen?
It consists of blood filled venous sinuses surrounded by splenic cords. the cords consist of red blood cells, macrophages, lymphocytes, plasma cells, and granulocytes
What is the function of the red pulp of the spleen?
Its primary role is blood filtration
What is the white pulp of the spleen?
It is lymphatic tissue consisting mostly of lymphocytes- lymphocytes aggregate around branches of the splenic artery.
What is the purpose of the white pulps of the spleen?
To carry out immune functions similar to the lymph nodes
In the superficial cortex of the lymph nodes, what types of lymphocytes are found there?
B cells
What are the two types of structures in the medulla of lymph nodes?
Medullary cords
Medullary sinuses
In the cortex of the lymph nodes, where are t cells found?
In the deep cortex
T/F cords are groups of cells and sinuses will have lots of lymph flowing through them.
True
The outer cortex contains what kind of lymphocytes?
B cells
The inner cortex has what kind of lymphoctes?
T cells
Dendritic cells
What are the cells of the medulla?
B cells
What is the route of flow through the lymph node?
Afferent lymphatic vessel– subcapsular sinus–trabecular sinus–medullary sinus-efferent lymphatic vessel
