Cell Bio Exam

Question 1

What is a malignant tumor?

Answer 1

tumour that spreads by invasion and metastatis. invades tissues, enters circulatory system (metastasits)

Question 2

what is a benign tumour?

Answer 2

tumour that grows in confined, local area. usually not life threatening

Question 3

What are the three categories of cancer?

Answer 3

1) Carcinoma: from epithelial cells (internal and external)
eg: lungs, breast, colon
2) Sarcoma: in supporting tissue
eg: bone, cartilage, connective tissue
3) Lymphoma & leukemia: from lymph and blood.

Question 4

What is cancer?

Answer 4

Based on a loss of growth control, producing tissue mass called tumours. Rate of cell division exceeds rate of cell loss.

Question 5

what are the 3 stages of metastasis?

Answer 5

1) cancer cells invade surrounding tissue & vessels
2) cancer cells are transported to distant sites by circulatory system
3) cancer cells reinvade & grow at particular sites

Question 6

What are some characteristics of cancer cells?

Answer 6

• Spreads by invasion/metastatis
• Has distinct appearance (large, irregular shaped, microvilli)
• Produce tumours when injected into lab animals
• Increased growth
• Chromosomal abnormalities

Question 7

What is immunology?

Answer 7

immune response to foreign matter and how responses are used to resist infection

Question 8

What is the immune system?

Answer 8

Adaptive defense system to protect from invading pathogenic organisms and cancer.

2 activities: recognition and response.

Question 9

what is immunity?

Answer 9

Protection from infectious disease (specific and non specific components) - innate and acquired

Question 10

what are the two types of immunity?

Answer 10

1) Innate: (non specific immunity) resistance to disease you are born with. lacks immunologic memory
2) Acquired: (specific immunity): required functional immune system. repeated exposure improves response/memory

Question 11

What are the 4 types of innate immunity defensive barriers?

Answer 11

1) Anatomic barriers: prevents entry into the body. 1st line of defense against infection. includes skin

2) Physiological barriers: temp-inhibits growth.
pH-fever response
soluble factors: lysozymes: cleaves bacterial
cell wall
interferons: induce antiviral in uninfected cells

3) Endocytic and phagocytic barriers: cells break down foreign matter and some phagocytes kill/digest whole microorganism.

4) inflammatory barriers: tissue damage/infection induce vascular fluid leakage. increase phagocytes into affected area.

Question 12

what are the 4 main characteristics of acquired immunity?
(immune response recognizes and eliminates foreign molecules)

Answer 12

1) antigenic apecificity: allows immune system to distinguish very subtle differences among antigens.

2) diversity: generates great diversity, recognizes billions of structures of foreign antigens.

3) immunologic memory: 2nd encounter induced heightened immune response

4) only responds to foreign antigens.

Question 13

what are the two branches of acquired immunity:

Answer 13

1) humoral: (antibody mediated immunity) B cells display and secrete antibodies
2) cellular (cell mediated immunity) : T cells directly attack infect cells.

Question 14

What is hematopoesis:

Answer 14

formation of red/white blood cells from stem cells

Question 15

what is multipotent?

Answer 15

every blood cell is derived from a stem cell.

Question 16

What causes cancer?

Answer 16

chemicals
radiation
viruses
genetics

Question 17

stem cell turns into lymphoid or myeloid.
lymphoid cells generate T and B lymphocytes.
myeloids generates red blood cells (erythrocytes), platelets, and white blood cells (leucocytes) including neurtorphils, eosineophils, basophils, monocytes, and mast cells.

What are lymphocytes?

Answer 17

make up 20-40% of bodys white blood cells. categorized by funciton and components.

B cell:
T cells
Null cell

Question 18

what are B lymphocytes?

Answer 18

matures in bone marrow. distiguished by presence of membrane bound antibodies ( B cell receptors)
B cell is activated when the antibody binds to antigen.
it differentiates into either
memory B cells (immunologic memory)
or effector cells (does not express membrane bound antibody but a secreted form)

Question 19

what are T lymphocytes?

Answer 19

matures in thymus.
has antigen binding recepetor called T cell receptor.
unlike B cells that recognize antibody, TCR recognizes antigen only when antigen is associated with a cell membrane protein.

Question 20

what are the two populations of T cells?

Answer 20

T-helper (TH)
T-cytotoxic (TC)