Lymphatic system

Question 1

function of the lymphatic system?

Answer 1

Tissue drainage
Return of plasma and plasma proteins
Absorbed fat transport from gut
Immunity

Question 2

Lymph composition?

Answer 2

lymph is fluid and plasma protein only.

Question 3

What is added to lymph as it flows through lymphatic capillaries and channels?

Answer 3

lymphocytes

Question 4

What is added to lymph in the small intestine?

Answer 4

fats

Question 5

How does lymph flow through vessels

Answer 5

relies upon muscle contraction, pressure changes and gravity.
Uni-directional because of valves that prevent back flow

Question 6

what happens to fluid flow during infection?

Answer 6

Fluid flow by osmosis into extracellular spaces increases (swelling) due to protein accumulation in ECF (ie antigens). This drives increased lymph flow and therefore immune response in nodes

Question 7

What are lymph nodes?

Answer 7

main lymphoid organ
acts as a checkpoint- closely regulates and inspects lymph fluid by immune cells (lymphocytes) within lymph nodes
trigger immune response if foreign pathogen traces are identified
- can be isolated or grouped

Question 8

Where is the first place the immune system sees an anitgen?

Answer 8

in the lymph node

on return of lymph to where it needs to be it transverses lymph node

Question 9

Lymph node- histology

Answer 9

kidney or oval shaped
lymphoid follicles:- primary and secondary
secondary have germinal centre with more WBC’s within these

Question 10

Checkpoints in the body other than lymph nodes

Answer 10

MALTs

Preyer’s patches

Question 11

MALTs

Answer 11

mucosa-associated lymphoid tissues
can be found in mucus membranes around the body outside of lymphatic vessels
example: tonsils which try to remoce pathogens before they enter the GI tract or lungs

Question 12

Preyer’s patches

Answer 12

checkpoint along the GI tract
in the distal portion of small intestine (bottom)
small mass of lymphatic tissue (aggregated lymph nodes) that monitor intestinal bacteria

Question 13

What would happen if the lymphatic system didn’t work effectively?

Answer 13

if fluid wasn’t returned to circulatory system (ie back to the blood)
then there would be a serious drop in BP and little to no O2 delivery or waste removal

Question 14

What is so bad about a tumour or blockage located in the lymphatic vessels?

Answer 14

tumour or blockage would be dangerous as it could lead to edema (abnormal accumulation of fluid in certain tissues) or swelling (which restrains blood flow)

Question 15

Where does the Right lymphatic duct drain to?

Answer 15

Drains all the lymph collected from the upper right area of the torso as well as the right arm and right side of the head and thorax and it feeds them into the internal jugular vein

Question 16

drainage by thoracic duct?

Answer 16

takes lymph from the rest of the body (everywhere not drained by right L.D) and feeds it into the subclavian vein

Question 17

Inflamed nodes?

Answer 17

if a node is overwhelmed by antigen that it’s trying to fight then it becomes enlarged and this can be an early sign of disease or infection

Question 18

Where are lymphocytes found?

Answer 18

in the loose reticular connective tissue that makes up a large part of the nodes and most of your other lymphoid organs

Question 19

Primary tumour (lymphoma) example

Answer 19

Hodgkins- rare cancer of the lymphatic system

Question 20

Secondary tumours

Answer 20

result of metastasis from other sites

Question 21

Examples of infections of the lymph nodes

Answer 21

tb

glandular fever

Question 22

what is the rule regarding deep lymphatic drainage route?

Answer 22

it follows routes of arterial supply

Question 23

Route of fat molecules through body

Answer 23

doesn’t go straight to the liver, instead, lymph returning from the small intestine is laden with absorbed fats which also drain to the superior vena cava and eventually to the liver for absorption

Question 24

Primary lymphoid tissue

Answer 24

thymus

where hematopoeitic stem cells are produced by bone marrow and differentiate into T-cells.

Question 25

Secondary lymphoid tissue

Answer 25

Secondary lymphoid tissues are sites where lymphocytes interact with each other and non-lymphoid cells to generate immune responses to antigens
e.g spleen, lymph nodes, peyer’s patches

Question 26

Spleen

Answer 26

largest lymphatic organ in the body
- upper left quadrant of abdomen (peritonised, peritoneum membrane)
contains a large amount of blood, routinely discharged via smooth muscle action

Question 27

Spleen histology

Answer 27

section of spleen has red pulp on outside, white pulp inside.
White pulp is where T and B cells are found.

Question 28

role of spleen

Answer 28

filter blood but also involved in immune response

Question 29

Where is there no lymph drainage from?

Answer 29

epithelium, cartilage, bone or CNS or from the majority of the spleen and liver

Question 30

Superficial inguinal nodes drain which part of the body?

Answer 30

everywhere from below the belly button except the gonads (an organ that produces gametes; a testis or ovary) and lateral foot