Question

1. part 1

cancer is a disease of uncontrolled cell division. cancer cells behave differently than normal cells, and function incorrectly during the cell cycle. which of these best describes how cell division irregularities might lead to cancer?
choose two correct answers.

cancer cells becomestuck in g1 of interphase, which causes each cell to grow excessively large.

cancer cells keep dividing and do not stop when overcrowded, leading to tumor formation.

cancer cells can divide many more times than normal cells in the body before they die off.

cancer cells remain too long in the dna replication part of interphase, which creates excessive copies of new cells.

cancer cells divide far less than normal cells, allowing each individual cell to increase in size.

part 2

Explanation:

• For the second option: Cancer cells lack contact - inhibition. Normal cells stop dividing when they become overcrowded (contact inhibition). Cancer cells do not, so they keep dividing and form tumors.
• For the third option: Normal cells have a limited number of cell divisions (due to telomere shortening). Cancer cells can divide many more times (because of telomerase activity that maintains telomere length) before they die off.

Answer:

• B. Cancer cells keep dividing and do not stop when overcrowded, leading to tumor formation.
• C. Cancer cells can divide many more times than normal cells in the body before they die off.