Immune system (p1)

Question 1

What are leukocytes?

Answer 1

Only formed elements that are complete cells (nuclei)

Protecting against bacteria, viruses, parasites, toxins, tumor cells

Call leave bloodstream (diapedesis) to mount immune response

Granulocytes (phils) and agranulocytes (cytes)

Question 1

What are the 5 types of leukocytes?

Answer 1

Never Let Monkeys Eat Bananas

Neutrophils, lymphocytes, monocytes, eosinophils, basophils

Question 2

What are neutrophils?

Answer 2

Make up more than half of all leukocytes

Cytoplasm contains types of granules that take up both acidic and basic dyes

• neutral staining properties

Called polymorphic leukocytes because they can take many shapes

• contain hydrolytic enzymes and some antibiotic like proteins (defensins)

Phagocytes = ingest and destroy bacteria

Granulocyte

Question 3

What are eosinophils?

Answer 3

Makes up 2-4% of all leukocytes

Has a blue-red nucleus often with two lobes

Primary function is fighting against parasitic worms, cannot be phagocytized but surround and release digestive enzymes

• has some immune responses to allergies and asthma

Granulocyte

Question 4

What are basophils?

Answer 4

Rarest WBCs

Cytoplasmic granules contain histamine

• can help as a chemical trail to help lead other WBCs to sites of injury/infection
• S or U shaped dark purple nucleus

Granulocyte

Question 5

What are lymphocytes?

Answer 5

2nd most common leukocyte

some in bloodstream but most in lymphoid tissue (lymph nodes, spleen…)

• T cells = act directly against virus infected cells, undergoes maturation at the thymus, known as soldier cells
• B cells = give rise to plasma cells that produce antibodies, undergoes maturation at the bone marrow

Question 6

What are monocytes?

Answer 6

Largest leukocyte

Differentiates into macrophages

• phagocytic in chronic infectiobs and against viruses, bacteria
• can act as antigen presenters - displaying some parts taken off a bacteria/virus they have found to alert other cells