Lymphoid tissues 2

Question 1

What 2 things is the lymphatic system comprised of?

Answer 1

Lymphatic vessels and secondary lymphoid tissue

Question 2

What is lymphoid tissue comprised of?

Answer 2

Primary, secondary, tertiary

Question 3

What happens in primary lymphoid organs?

Answer 3

Lymphopoiesis

Question 4

What are 3 primary lymphoid organ?

Answer 4

Thymus
Bone marrow
Fetal liver

Question 5

What are the 3 lymphocytes?

Answer 5

B cells
T cells
Natural Killer cells

Question 6

What cells is the adaptive immune response comprised of?

Answer 6

B and T cells

Question 7

What are the 2 hallmarks of the adaptive immune response and describe them?

Answer 7

Specificity – provided by a vast range of unique T cell and B cell receptors

Memory – rapid expansion in response to secondary encounter

Question 8

What bones does hematopoiesis most occur in in adults?

Answer 8

Flat bones, but also vertebrae and ends of long limb bones

Question 9

What does repertoire mean?

Answer 9

The range of genetically distinct BCRs or TCRs present in a given host

Question 10

Where do B cells undergo final differentiation (repertoire generated)?

Answer 10

Bone marrow

Question 11

Where does final maturation of B cells occur?

Answer 11

The periphery

Question 12

Where are immature T cells produced?

Answer 12

Bone marrow

Question 13

Where do T cells mature?

Answer 13

The thymus

Question 14

What are the 2 types of selection T cells undergo?

Answer 14

Positive and negative selection

Question 15

What is positive selection?

Answer 15

T cell is asked whether it can recognise an antigen

Question 16

What is negative selection?

Answer 16

Tests if it reacts against our own body

Question 17

What happens to T cells that fail the selection?

Answer 17

Apoptosis

Question 18

What is thymic involution?

Answer 18

The shrinking of the thymus with age

Question 19

What is thymic involution associated with?

Answer 19

Change in structure and reduced mass

Question 20

Does T cell output increase or decrease with age?

Answer 20

Decrease

Question 21

Does thymus get more or less fatty with age?

Answer 21

More fatty

Question 22

How many TCR sequences per T Cell?

Answer 22

1

Question 23

How many TCR sequences do genes allow for?

Answer 23

10^15- 10^20

Question 24

How many T cells do we have?

Answer 24

3.75x10^11

Question 25

What happens at secondary lymphoid tissues?

Answer 25

Lymphocytes interact with antigens and other lymphocytes

Question 26

Name 4 secondary lymphoid organs

Answer 26

Spleen Lymph nodes Appendix Mucosa-associated lymphoid tissue

Question 27

How are lymphoid tissues interconnected?

Answer 27

Via lymphatic system and the blood

Question 28

Why are lymphoid tissues beneficial?

Answer 28

Bring cells in close proximity to antigen

Question 29

Do lymph nodes have distinct regions for B and T cells?

Answer 29

Yes

Question 30

What are the 2 categories of lymphatic vessels in lymphatic tissue?

Answer 30

Afferent and efferent

Question 31

What is the first line of defence against infection

Answer 31

Epithelial barriers

Question 32

What type of barrier is an epithelial barrier?

Answer 32

A physical barrier

Question 33

What type of lymphoid tissue is located in the gut and what is it called?

Answer 33

Specialized secondary lymphoid tissues called Peyer’s patches

Question 34

Where exactly are Peyer's pathes found?

Answer 34

Below the epithelium of the ileum of the small intestine.

Question 35

What are Peyer's patches enriched with?

Answer 35

Germinal centres

Question 36

What are the 4 types of tonsils?

Answer 36

Pharyngeal, tubular, palantine and lingual

Question 37

What ring do the 4 types of tonsil create?

Answer 37

Waldeyer ring

Question 38

How often does each naïve T cell recirculate?

Answer 38

Once every 24 hrs

Question 39

What is the purpose of dendritic cells?

Answer 39

Antigen presentation

Question 40

What are the two types of dendritic cells in relation to movement?

Answer 40

Tissue resident and migratory

Question 41

How do DC migrate into lymph nodes?

Answer 41

Via the afferent lymph into lymph nodes