Chapter 12

Question 1

How is cancer characterized by

Answer 1

Uncontrolled cell division and metastasis (the ability to spread to other parts of the body)

Question 2

How do we know cancer and genetics are related?

Answer 2

A inherited predisposition exists for more than 50 forms of cancer. Most chemicals that cause cancer are also mutagens.

Question 3

What is the main source of all cancers?

Answer 3

Epithelial cells are the source of 80-90% of all cancers

Question 4

How does cancer develop?

Answer 4

Cancer begins in one cell. Mutations accumulate over time and divide continuously in cell cycle. Cancer cells can be invasive and can infiltrate surrounding tissues or metastasize and move to other parts of the body

Question 5

What determines whether the cancer is sporadic or inherited?

Answer 5

It’s inherited if a mutant allele is inherited from one parent and the second allele mutates, it causes loss of heterozygosity. sporadic cancer is caused by the gradual accumulation of mutations in key genes within a single cell.

Question 6

What are the gene categories associated with cancer?

Answer 6

1. Cell cycle regulation genes
2. DNA repair genes
3. Hybrid genes from translocations

Question 7

What are the cell cycle checkpoints ?

Answer 7

G1/S: signal transduction
G2/M: ensures that DNA has been replicated accurately and any DNA damage is repaired
M: ensures proper attainment of spindle fibers to chromosomes