Does the cell cycle ever go wrong Sometimes

Does the cell cycle ever go wrong? Sometimes the cell cycle goes out of control and experiences uncontrolled cell division.

This uncontrolled growth creates a tumor.

There are 2 types of tumors: 1. Benign - An abnormal mass of NORMAL cells 2. Malignant - Masses of cells that result from the reproduction of CANCER cells

CANCER

Why should we study cancer?

What causes cancer? Carcinogens (substances that mutate our DNA causing our cells to divide uncontrollably)

RECAP! Carcinogens DNA mutations Mistakes in the cell cycle Uncontrolled division CANCER!!

Why is it more common for older people to get cancer?

Every time our cells divide, the risk of a messup becomes greater! Older people have cells that have divided more times!

How does cancer spread? Metastasis: the spread of cancer cells beyond its original site Travels to different parts of the body through the blood stream!

How is cancer treated?

Surgery Removes tumors and cancerous cells from the body

Radiation Tumors are exposed to high energy radiation This disrupts the cell cycle!

Chemotherapy Drugs to disrupt cell division

Why is family history important when talking about cancer? We get the instructions for our DNA from our parents. If our parents’ DNA instructs our cells to make a mistake while dividing, there is a good chance our cells will do the same thing.

Retinoblastoma This cancer is caused by a mess-up in the copying of a special protein called RB 1. Usually young children get retinoblastoma.

How do our cells check and try to prevent cancer? ? ? Our cell cycle has checkpoints!

How can I help my body prevent getting cancer?

NO SMOKING!!!!

What can I eat to help prevent me from getting cancer?

Why do these foods help prevent cancer? ANTIOXIDANTS Antioxidants are substances that may protect your cells against the effects of free radicals. Free radicals can damage cells, and may play a role in heart disease, cancer and other diseases.

If I get cancer how can my body fight it?

Your body’s immune system spots cells that don’t belong and destroys them!

So, how does the immune system work? First, the body tries to keep things out.

Even though our skin is very tough and usually does a great job of keeping out intruders, sometimes they still get in.

When invaders enter our body, cells are destroyed. These dying cells trigger an automatic response called inflammation. This inflammation is like the burglar alarm for your cells.

How does our immune system know which cells are the intruders? Each pathogen (a microscopic organism that causes sickness) has an antigen. An antigen is a foreign substance that triggers a reaction from the immune system.

There are several specialized cells in our immune system that help keep our bodies safe from pathogens.

Macrophages “big eaters” finds and eats bacteria viruses, and dead or injured body cells

B cells and T cells Have special receptors on their cell membranes that help them connect to specific antigens

T cells There are 2 types of T cells: 1. Helper T cells 2. Killer T cells

Helper T cells -Help B cells make antibodies -Are activated by macrophages

Killer T cells -Attack cells of the body infected by viruses -Attacks cancer cells

B cells There are 2 types of B cells: 1. Plasma cells 2. Memory cells

Plasma cells -Produces antibody -Responds to the same antigen that matched the helper T cell

Antibodies are released from plasma cell so they can seek out intruders and help destroy them.

Memory Cells -Remember specific intruders

There are 2 types of immunity. 1. Passive Immunity - Immunity that we get from our mothers before and after birth. - Last for a short period of time! 2. Active - Immunity that our bodies develop continually from birth - These are our antibodies that defend against specific antigens.

What can we do to help our immune system fight off pathogens?

Vaccines expose your body to a harmless version of a specific disease. Your body destroys the cells in the vaccine and creates memory cells so that it can respond to and destroy the actual pathogen quickly if it enters the body.

Antibiotics either kill or prevent bacteria from growing. Antibiotics ONLY work on bacteria, NOT on viruses