Part 2: Lymphoid System

Question 1

A collection of tissues and organs that are designed and located to bring population of B and T cells into contact with any and all antigens that enter the body

Answer 1

Lymphoid system

Question 2

The site where lymphocytes are gathered to contact antigens

Answer 2

Peripheral lymphoid organs

Question 4

What are the peripheral lymphoid organs?

Answer 4

Lymph nodes, spleen, appendix, tonsils and adenoids

Note: tonsils and adenoids are questionably lymphoid

Question 5

Lymph nodes store and circulate

Answer 5

Lymphocytes

Question 6

Lymph node germinal center contains dividing

Answer 6

Lymphocytes

Question 7

Functions to filter blood and destroy old erythrocytes

Answer 7

Spleen

Question 8

Lymphocytes are produced in the __ while blood fills ___

Answer 8

White pulp; red pulp in the spleen

Question 9

What happens in the primary lymphoid organs?

Answer 9

Hematopoietic stem cells mature to become T and B cells

Question 10

Only after ___ is a lymphocyte immunocompetent

Answer 10

Maturation

Question 11

What is a syndrome associated with T cell deficiency, heart problems and facial changes?

Answer 11

DiGeorge syndrome

Question 12

Is a child or adult thymus larger?

Answer 12

Child

Peak size is seen during puberty; peak activity in childhood

Question 13

After childhood, the thymus is replaced with

Answer 13

Fat

Question 14

What is thymic education?

Answer 14

Differentiation of thymocytes (immature T cells)

Question 15

Thymocytes develop into:

Answer 15

CD3 T cells (helper)

CD8 T cells (cytotoxic)

Question 16

What are the 2 types of helper T cells?

Answer 16

TH-1 induce cell mediated immune response

TH-2 activate B cells to produce antibody (humoral)

Question 17

What do cytotoxic T cells do?

Answer 17

Destroy virus infected cells and tumor cells

Question 18

When thymus selects T cells that are functional (AKA does not kill self) what kind of selection happens?

Answer 18

Positive selection

Note: they are chosen because they are not auto reactive and they go after foreign antigen specific

Question 19

T cells in the thymus that are not functional, aka they try kill self, are negatively selected and what happens?

Answer 19

Apoptosis (programmed cell death)