Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PSYCH > Lymphoid Tissues > Flashcards

Lymphoid Tissues Flashcards

1
Q

What are primary lymphoid tissues?

A

The site of lymphopoiesis, where new lymphocytes are made, the bone marrow and the thymus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How is lymph forms?

A

Through the draining of interstitial fluid out of the capillaries and into the lymphatic vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the two primary lymphatic organs?

A

The bone marrow and thymus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What cells are of the lymphoid lineage?

A

T cells, B cells and NK cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which part of the bone marrow does haematopoiesis occur on?

A

The red part

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What cells are made in the bone marrow? And which part of the bone marrow?

A

B cells in the yellow marrow in the middle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which cells mature in the thymus?

A

T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is meant by thymic involution?

A

When the thymus output massively decreases over time, and most if thymus is replaced by fat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the two selection processes which the T cells undergo?

A

Positive and negative selection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is positive selection?

A

T cells with CD4 and CD8 proteins on surface will try bind MHC1 and MHC2. if it does, this is good as the correct proteins were expressed, and cell is not killed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is negative selection?

A

Keeping the cells that don’t bind and interact with self peptides
If the TCR recognizes self peptides then apoptosis is triggered

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How do the T cells differentiate into T Helper Cells and T Killer cells?

A

Depending on which out of CD4 or CD8 had the strongest bond, the T cell will up regulate that one

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does the thymus change with age?

A

Degenerates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does the number of peripheral T cells change with age?

A

Remains the same - peripheral T cells numbers are maintained by the division of mature T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why are older people more vulnerable to new strains of pathogens?

A

Due to thymic involution, the T cell numbers are maintained by the division of mature T cells outside the central lymphoid organs, therefore you get less variety of T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How do T cells move from their site of production?

A

The thymus releases chemokines initiate the chemotaxis of T cells from the bone marrow to the thymus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens to the thymus during infection?

A

No change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What happens to the bone marrow during infection?

A

Bien marrow increased white cell production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are secondary lymphoid tissues?

A

They are the locations where lymphocytes can interact with antigens and other lymphocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are some secondary lymphoid tissues?

A

Spleen, peyers patches, gut, lymph nodes,tonsils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are lymph nodes?

A

Highly organized, encapsulated structures which are located at points of convergence of lymphatic vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are germinal centers?

A

Anatomically restricted site where B cells undergo maturation and selection to generate high affinity antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Through what vessel does lymph enter into the lymph nodes?

A

The afferent lymphatic vessel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the functions of the spleen?

A
  1. Store of platelets
  2. Reacts with blood borne antigen
  3. Removes defective RBCs from circulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Why is the lymph nodes a discrete tissue?
It has no other function other than to act as a site where lymphocytes and antigen can interact
26
What form the first line is defense against infection?
Epithelial barriers
27
What is the significance of the location of lymphoid tissues?
They are spread around the body so that the lymphatic sin every part of the body can reach, allowing lymphocyte and antigen interactions
28
Where are Peyer’s Patches Found?
Below the epithelium of the ilium of the small intestine
29
Where are many germinal centers located?
The gut
30
Why is there a lot of germinal centers in the gut?
There are high levels of antigen coming from gut microbial, which are producing many foreign antigens which leads to high antibody production
31
What happens in the red pulp of the spleen?
Red blood cells are destroyed
32
What is a Periarteriolar lymphoid sheath?
An area of white pulp which surrounds the arteries running through the spleen - is highly populated with T cells
33
What is MALT?
Mucosa-associated lymphoid tissues
34
Which special cells do gut associated lymphoid tissues contain?
M cells (membrane-like) or FAE (Follicle associated Epithelial) cells
35
What do FAE cells do?
- take up small amount of gut antigen - pass onto APCs - B lymphocytes react, making type IgA antibodies which are secreted directly into the gut lumen
36
What do the IgA antibodies made in the gut do?
They prevent microorganisms in the gut from sticking to the gut epithelium, and can also neutralize toxins and viruses
37
What forms the Waldeyer ring?
The pharyngeal, tubular, palatine and lingual tonsils
38
What are the tonsils made of?
Epithelial cells that are able to phagocytosis bacteria and transfer the antigenic peptides to macrophages that act as APCs
39
Where are the antigen sampled from in the tonsils?
Directly from the external environment
40
Why is the waldeyer ring an ideal environment for the immune system to encounter antigen?
Food, bacteria and things we breath in pass the oral pharyngeal section very often, therefore more antigen
41
Why do lymph nodes swell during an infection?
The B cell follicles of the lymph nodes expand as the B cells proliferate to form germinal centers, amd the entire lymph node enlarges
42
Where do naive Lymphocytes go after they are produced?
They enter into the blood stream and migrate to the peripheral lymphoid tissues
43
How long does it take for a T cell to recirculate?
24 hours
44
How to lymphocytes get inside the lymph nodes?
They enter via high endothelial venules
45
Where are high endothelial venules found?
In T cell zones of the lymph nodes
46
Which organ is mainly associated with filtering antigen out of blood?
Spleen
47
What are the four steps of T cells getting inside the lymph nodes?
1. Rolling 2. Activation 3. Adhesion 4. Transendothelial migration
48
What molecule on T cells results in the rolling of the T cell before it enters the T cell zone of the lymph nodes?
L Selectin on T cell
49
What molecules binds to L selectin?
CD34
50
What chemokines are involved in activating LFA-1
Recognition of CCL21 on endothelial surface of HEV by CCR7 on T cells
51
What happens when LFA1 is activated?
The affinity for ICAM-1 AND ICAM-2 is increased
52
What does ICAM allow?
The migration of the lymphocytes through the blood vessel wall
53
What are dendritic cells?
Potent, antigen presenting cells that pick up and bring antigen from sites if infection to secondary lymphoid organs
54
How to dendritic cells help with the adaptive immune response?
They pick up antigens and present them to T cells, in order to activate the T cells
55
How do dendritic cells display the antigens?
Through MCHII molecules
56
Describe the transport of lymphocytes and antigens in the lymphatics and blood stream
Free antigen and antigen bearing DC’s travel from the site of infection through afferent lymphatic vessels into the draining lymph nodes Activate lymphocytes then undergo period of proliferation and differentiation- once mature then leave through efferent vessels
57
What is an example of a DC?
Langerhans cells in epidermis
58
Describe what is meant by 'repertoire' in terms of lymphocytes?
The range of **genetically distinct** BCRs or TRCs present in a given host The larger the repertoire, the more threats can be recognised
59
Where in lymph nodes generally are the T cells found relative to B cells?
T cells - Towards inside (further from the marginal sinus) | B cells - Towards outside (closer to the marginal sinus)
60
What do the words afferent and efferent refer to respectively?
Afferent - the vessel the lymph enters into the lymph nodes via Efferent - the vessel the lymph leaves the lymph nodes via
61
What is it that makes the spleen so good at filtering antigens from the blood?
It is **highly attached** to the arterial circulation via the **splenic artery** So it can filter blood rapidly and in **large numbers**
62
What is it that makes the spleen so good at filtering antigens from the blood?
It is **highly attached** to the arterial circulation via the **splenic artery** So it can filter blood rapidly and in **large numbers**
63
How do specific T cells become activated by their specific antigen which is in a different part of the body?
Each naive T cell recirculates once every 24 hours They enter Lymph nodes with antigens (lymphatic vessels) Become activated by binding to antigens from lymphatic vessels Leave via efferent lymphatic vessel Travel from peripheral tissue and inflammation occurs The lymphatic vessels enter the lymph node via the afferent lymphatic vessels
64
What does lymph do?
Transports dietary lipids, drains interstitial fluid and facilitates immune responses
65
What are the 2 steps involved in extravasation of naïve T cells into lymph nodes?
Selectin binding Integrin binding
66
Define antigen presentation
The display of peptides in the major histocompatibility complex (MHC) I or II proteins such that the T cell receptor can attempt to bind them
67
How do dendritic cells transport antigens from site of inflammation to the secondary lymphocyte tissues?
Once dendritic cells uptake antigen They migrate out of the inflamed tissue Carry antigen towards the T cells and B cells

PSYCH (78 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions