Interphase Mitosis Cytokinesis The Cell Cycle Interphase Mitosis Cytokinesis

A lot of the energy produced during respiration is used for cell movement movement of cells from one location in an embryo to another during embryonic development movement of cells into a wound during wound healing contraction of a muscle cells separation of a cell into two daughter cells during cell division movement of substances during active transport movement of chromosomes during mitosis

Cells also use energy to make copies of themselves in the CELL CYCLE

How Cells Work (16 min)

Length of Cell Cycle (liver cell) 1 hour

Stage 1: Interphase Step1of the cell cycle Longest part of the cell’s cycle a. Cell grows and develops b. DNA is replicated (along with organelles and other cellular components) c. Cell prepares for division Textbook pages 66 &67 Page 3&4 of your booklet

Cell Cycle: Stage 1 Interphase (4.5 min)

Mitosis Prophase Metaphase Anaphase Telophase

Stage 2:Mitosis Step 2 of the cell cycle Prophase- chromatin condenses into chromosomes (chromosomes are visible) each chromosome consists of sister chromatids held together by a centromere Nuclear membrane disappears Nucleolos disappears Pages 5&6 of your booklet

Prophase (3.5 min)

Stage 2:Mitosis Metaphase- Step 3 of the cell cycle Metaphase- Chromosomes line up in the center of the cell Spindle fibers attach to the center of each chromosome Page 7&8 of your booklet

Metaphase (30 sec)

Stage 2: Mitosis Step 4 of the cell cycle Anaphase- Chromosomes split Each half is pulled to opposite ends of the cell Pages 9&10 of your booklet

Anaphase (30 sec)

Stage 2: Mitosis Step 5 of the cell cycle Telophase- Chromatids cluster in the center of each new cell new nuclear membranes form around the chromatids Cell begins to separate Pages 11&12 of your booklet

Telophase (1.5 min)

Stage 3: Cytokinesis Step 6 of the cell cycle - The cytoplasm divides Two new daughter cells are formed and the cycle begins again Pages 13&14 of your booklet In a plant cell- a new cell membrane forms first, then a new cell wall forms vesicles In an animal cell- the cell membrane pinches in (furrowing)

Length of Cell Cycle (liver cell) 1 hour

Video on cell division, mitosis and cytokinesis Mitosis Link The only human cell that does not go through cell division is the Brain Cell

DNA Replication and Cancer DNA= Deoxyribonucleic acid

DNA Replication Occurs during interphase. This ensures each new daughter cell will have the genetic information it needs to carry out its activities In 1953, James Watson and Francis Crick discovered the structure of DNA

Structure of DNA DNA looks like a “twisted ladder” It is a double helix The sides of the ladder are sugars (deoxyribose)and phosphates The rungs of the ladder are pairs of nitrogen bases

Nitrogen Bases There are four different types of nitrogen bases Adenine Thymine Guanine Cytosine Adenine and Thymine pair together Guanine and Cytosine pair together

DNA replication

What do DNA mutations look like? A typical Westlake teenager after a DNA Mutation!!!!

DNA REPLICATION (4 min)

Cancer- What is it? A disease in which cells grow and divide uncontrollably This can damage the parts of the body around them There are about 200 different forms of cancer 2015 - Skin Cancer is the #1 type of cancer diagnosed in the US (2,000,000 new cases) 2015 – Lung Cancer is the #1 cause of death in the US (160,000 new cases)

What Causes Cancer? When something damages a portion of the DNA in a chromosome This damage causes a change in the DNA called a mutation http://www.cancer.gov/newscenter/benchmarks-vol1-issue4/Video

What Causes Cancer? (Continued) This mutation causes cells to grow and divide at an abnormal rate This leads to a mass of cancerous cells, called a tumor Some of these cancerous cells can break off from the tumor, enter the bloodstream, and spread to other parts of the body This is called metastasis A mutation disrupts the cell cycle causing the cell to function abnormally. Exposure to some Chemicals and radiation are some common causes of mutations that lead to cancer

How is Cancer Treated? Surgery- remove the tumor Radiation- killing the cancerous cells using radioactivity (gamma rays). Helps to shrink the tumor Chemotherapy- killing the cancerous cells using drugs Some causes of cancer…smoking, unhealthy diet, tanning beds, air pollution, UV radiation, genetics Can cancer be prevented? Yes!! Don’t smoke Eat a low fat, healthy diet leafy green veggies. (fructose has been linked to aiding in cancer cell growth) - sunscreen

Repair genes (2min)

Mutated Suppresser Gene P53 (7:30)

Cancer Video (7 min)

Skin Cancer and New Treatments Video (7min)