Primary lymphoid tissues

Question 1

What are the primary lymphoid tissues?

Answer 1

Bone marrow and thymus

Question 2

Another name for primary lymphoid tissues?

Answer 2

Central lymphoid organs

Question 3

What cells are immune cells derived from?

Answer 3

haematopoietic stem cells

Question 4

Other than immune cells, what do haematopoietic stem cells also become?

Answer 4

Platelets and red blood cells

Question 5

Two types of bone marrow

Answer 5

Red and yellow

Question 6

What is red bone marrow involved in?

Answer 6

Haematopoiesis

Question 7

What is yellow bone marrow made up of?

Answer 7

Adipocytes

Question 8

At birth, where does haematopoiesis occur?

Answer 8

all medullar cavities of bone

Question 9

Where is haematopoiesis restricted to in adulthood?

Answer 9

Axial skeleton

Question 10

In adulthood, what do the medullary cavities have in them?

Answer 10

Adipocytes

Question 11

What are both T cells and B cells derived from?

Answer 11

Common lymphoid progenitor

Question 12

Where do B cells develop and mature?

Answer 12

Bone marrow

Question 13

Where do T cells mature?

Answer 13

Thymus

Question 14

Where is the thymus?

Answer 14

Superior and anterior mediastinum, superficial to the heart and posterior to the sternum

Question 15

When is the thymus the largest and most active?

Answer 15

In childhood

Question 16

Where are T cells that recognise self MHC positively selected for?

Answer 16

Cortex of thymus

Question 17

What percentage of T cells fail positive selection?

Answer 17

95%

Question 18

What presents T cells in the cortex with MHC?

Answer 18

Cortical epithelial cells

Question 19

Where does negative selection of self reactive T cells occur?

Answer 19

Medulla

Question 20

What cells present peptides in the medulla?

Answer 20

Dendritic cells