Lymphatics, Immune system

Question 1

Antigen vs Antibody

Answer 1

Antigen: suface cell marker (body may perceive as foreign)
Antibody: a protein that targets a specific antigen

Question 2

Functions of the lymphatic system

Answer 2

Produces,maintains, distributes lymphocytes
Maintains net filtration pressure (to move blood from arteries into vessels)
Hormone/nutrient/waste distribution
Filters out foreign substances (aged/infected/cancerous cells)

Question 3

Lymph pathway (arteries to veins) - acronym

Answer 3

A- Can I Come Vacuum The Den - V
Arteries
Bloodstream capillaries
Interstitial space
Lymphatic capillaries (some to veins)
Lymphatic vessels
Lymphatic trunks
Lymphatic ducts
Veins

Question 4

Lymphatic capillaries:
What type of ends
Permeable?
Valves?
Anchored how?

Answer 4

Blind ended
Very permeable
One way valves
Anchored with collargen fibres

Question 5

Lacteal
What kind of vessel?
Found where
What nutrient does it send straight to bloodstream?

Answer 5

Lymphatic capillary
Small intestine villi
Absorbs fat, send straight to bloodstream (as chyle) (skips first pass in liver)

Question 6

Lymphatic vessels:
Do what frequently?
Travel alongside which vessels?

Answer 6

Anastomose frequently
Blood arteries and veins

Question 7

Lymphatic trunks
Thoracic duct drains what
RIght Lymphatic duct drains what

Answer 7

Everything inferior to diaphragm + left side of body superior to diaphragm
Right side of body superior to diaphragm
(75/25 split)

Question 8

Lymph transport
List ways that are similar to venous return
Other ways

Answer 8

Breathing helps change pressure, one way valves + skeletal muscle milking (squeezing)
Pulsation of nearby arteries
Smooth muscle contraction (in lymphatic walls)

Question 9

3 classes of lymphocytes (antibodies)

Answer 9

T cells
B cells
NK cells

Question 10

Macrophages: function (specific?)

Answer 10

“eat” anything that seems foreign
Presents info on foreign substances to T/B cells

Question 11

Primary lymphoid organs: function + examples

Answer 11

Where B/T cells mature
Bone marrow + thymus

Question 12

Secondary lymphoid organs: function + examples

Answer 12

Where B/T cells encounter antigens
Lymph nodes, spleen, etc

Question 13

Lymphocyte development
Origin
Maturation
Seeding (dormant + circulate)
Antigen encounter
Proliferation/differentiation (what happens upon antigen encounter)

Answer 13

Origin: B/T cells in bone marrow
Maturation: B cells stay in bone marrow, T cells mature in thymus
Seeding: remain dormant in secondary lymphoid organs, circulate blood/lymph
Antigen encounter: lymphocyte antigen receptor binds to specific antigen
Proliferation/differentiation: effector cells make antibodies, memory cells wait for secondary response

Question 14

Thymus:
What does it educate?
Positive selection?
Negative selection?
Rate of failure?
Larger in adults or children?

Answer 14

T cells
Positive selection: T cells must recognize self MHC
Negative selection: T cells must NOT recognize self-antigen
>99% of T cells fail, apoptose
Largest in children, gone by 25

Question 15

Lymphoid tissue
Function, special regions?

Answer 15

Proliferation zone for lymphocytes
In areas of high-probability of antigen encounter
Diffuse lymphatic tissue: found in most organs
Lymphoid follicles/nodules: B-cell germinal centers (first line of defence for food/air)

Question 16

Lymph nodes
Filter what?
Activate what when needed?
2 parts of structure

Answer 16

Filer LYMPH
Mount immune response (lymphocytes) if needed
Cortex: germinal centers for B cell proliferation
Medulla: contains B/T cells + macrophages

Question 17

What slows down flow through lymph nodes?
Why

Answer 17

Hilium
To allow time for antigen scanning before sending lymph to next lymph node

Question 18

Spleen
Filters what?
Stores what? Why?
2 components, contain what

Answer 18

(Largest lymphoid organ)
Filters BLOOD (takes out aged cells, pletelets, debris)
Stores broken down iron, platelets, monocytes for recycling in new cells
White pulp (white blood cells (B/T cells)
Red pulp (red blood cells, macrophage destroys old RBCs)

Question 19

Mucosa associated lymphoid tissue (MALT)
Function
Locations

Answer 19

Protects digestive/respiratory systems from foreign matter
Tonsils, peyer’s patches, appendix (all secondary lymphoid organs)

Question 20

1st line of defence:
examples, function

Answer 20

Skin: slightly acidic, keratin for extra protection
Mucous membranes (inside the body membranes): mucous (containing microorganisms) propelled by cilia to throat -> stomach acid for break down

Question 21

2nd line of defence
Specific/non-specific?
Examples

Answer 21

Non-specific
Phagocytes: eat all foreign substances that break membrane
NK cells: use perforin to perforate + lyse foreign cells
Interferons: released by dying cell to warn surrounding cells (mobilize immune system)
Complement: use Membrane Attack Complex (MAC) to lyse microorganisms
Inflammation: sending more blood to area for healing + flushing out
Fever: stops microorganisms from growing, helps repair process

Question 22

3rd line of defence
Specific/non-specific?
Examples

Answer 22

Specific (adaptive)
Humoral immunity: B cells
Cellular immunity T cells

Question 23

Humoral immunity
acronym, brief explanation

Answer 23

PLAN
Precipitation: foreign cells are clumped for easier macrophage access
Lysis: complement uses MAC
Agglutination: like precpitiation
Neutralization: masking of dangerous parts of the pathogen (eliminates harm)

Question 24

Primary response vs secondary response

Answer 24

Primary: firs encounter with antigen
B cells proliferate, make plasma cells, make antibodies + memory cells (DELAY, LOW # of ANTIBODIES)
Secondary: next encounter, up to years later
MEMORY B CELLS make plasma cells, make antibodies + more memory cells (NO DELAY, MORE ANTIBODIES, STRONGER RESPONSE)

Question 25

2 Types of humoral response
Active immunity: sources
Passive immunity: sources

Answer 25

Active immunity: from infection/vaccination
Passive immunity: from placenta/breastfeeding (short term no memory cells), antibody injection (also no memory cells acquired)

Question 26

Classes of B cells
IgM: present when?
IgA: found where?
IgD: found where on B cell?
IgG: crosses? during which humoral response?
IgE: present when?

Answer 26

IgM: primary response
IgA: in secretions
IgD: B cell surface
IgG: only one to cross placenta. during late primary/secondary response
IgE: present during inflammation/allergic reactions

Question 27

Cellular immunity
Which type of cells? B or T
2 types of cells (present antigens)

Answer 27

T cells
MHC1/MHC2 cells

Question 28

MHC1:
what message?
what is activated as result?

Answer 28

“I am infected, see something like me, kill it.”
Cytotoxic (specific) T cells activated

Question 29

MHC2:
what message?
what is activated as result?

Answer 29

“Look at this infected cell, if you see one like it, kill it”
Helper T cells activates (very general immune response)