Cancer

Cancer

Module D | Cell Transport, Processes, and Energy

Lesson Essential Question

What are the effects of uncontrolled cell growth?

Multiple Choice

During which stage of the cell cycle does the cell divide?

• G1

• G2

• S

• M

Review

Module D | Cell Transport, Processes, and Energy

Cell Division Review

Cells divide within the body for growth, repair of damaged tissues, and to replace dead cells.

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This process of cell division, however, must be carefully regulated.

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If not, disease (cancer) can occur.​

Module D | Cell Transport, Processes, and Energy

Lesson Note Headings

1. How is the cell cycle controlled?

2. What is cancer?

3. How is cancer caused?

4. How is cancer treated?

How is the cell cycle controlled?

The cell cycle is controlled by regulatory proteins both inside and outside the cell.

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• Inside: Proteins act as checkpoints within the cell cycle; prevents a cell from moving into mitosis until certain conditions are met

• Outside: Proteins act to speed up or slow down; "growth factors" help to prevent excessive cell growth ("cyclins")

Module D | Cell Transport, Processes, and Energy

How is the cell cycle controlled?

As new cells are produced, other cells die. Some will die by accident or injury; others are "programmed" to die.

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Programmed cell death = apoptosis

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​When cells lose their function to control growth, cancer develops.

Module D | Cell Transport, Processes, and Energy

Open Ended

Explain why apoptopsis is important to cell growth.

What is Cancer?

Cancer cells do not respond to the signals that regulate the growth of most cells. As a result, the cell cycle is disrupted, and cells grow & divide uncontrollably.

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This clump of cells = a tumor

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Some ​tumors are benign (non-cancerous); others are malignant (cancerous).

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Module D | Cell Transport, Processes, and Energy

What Causes Cancer?

Cancers are caused by defects in the genes that regulate cell growth & division.

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Defects can come from various sources.

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Many cancers have defects in the checkpoint protein p53 (which pauses mitosis until the chromosomes have been replicated correctly).​

Module D | Cell Transport, Processes, and Energy

How is Cancer Treated?

Cancer treatments include:

• surgery

• radiation treatments; and,

• chemotherapy.

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Researchers are also considering gene therapy as a means to combat cancer.

Module D | Cell Transport, Processes, and Energy

Open Ended

Why would a defective p53 gene lead to cancer?

Sum It Up

Write your summary & show it to Mr. Buie to receive credit​.