7. Cell Cycle, Death & Cancer

Cell Cycle Checkpoints?

Cell Cycle Checkpoints:

1st Check: Growth (Gap) 1

○ Is there enough nutrients?

• Damaged DNA?

2nd Check: Growth (Gap) 2

○ Did the DNA replicate?

• Damaged DNA?

3rd Check: Cytokensis

○ Are Chromosomes still attached?

○ Did they successfully separate?

Therefore, Cell division does not occur if:

Therefore, Cell division does not occur if:

• Dont have enough nutrients.

• DNA not doubled

• DNA damage

What happens in Growth (Gap) 1?

Growth

What happens in Synthesis (S)?

DNA is copied

What happens in Growth (Gap) 2?

• Shortest

• Prepare for division

Cell Death

We use the term “ ______ ” to describe pre-programmed cell death.

Cell Death

We use the term “ Apoptosis ” to describe pre-programmed cell death.

Cells undergo ____ rounds of division before dying

Cells undergo 20 - 30 rounds of division before dying

A cell’s death, when pre-programmed, is actually healthy! why?

A cell’s death, when pre-programmed, is actually healthy!

● Replace old cells

● Stops damaged cells from dividing

• mutations is Caused by?

• that do what?

• Caused by a mutagen (UV light, X-rays, gamma rays) or simply by chance,

• and they change the genetic code.

Codons ?

From what?

Note* Specific pairing: ?

Codons

• (3 Letter Codes)

• from 4 main ‘blocks’ A - T - C - G

Note* Specific pairing:

• Apple–Tree (A–T)

• Car–Garage (C–G)

Tumors & Cancer

• A mutated cell could avoid?

Tumors & Cancer

• A mutated cell could avoid Apoptosis (stop dividing & die)

2 Kinds of Tumors: ?

2 Kinds of Tumors:

Benign

• Non - Cancerous, doesn't effect surrounding cells

Malignant

• Cancerous cells, traveling through blood and interferes with function of healthy cells, potentially causing more tumors

tumor?

The rapid and uncontrolled division of cells is known as a tumor.

The two overarching causes of cancer are?

The two overarching causes of cancer are

• genetic (inherited mutations)

• environmental/lifestyle factors.