Warm-Up 11/15/10

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Warm-Up 11/15/10. LIST the Phases of the Cell Cycle. Which Phase of the CELL CYCLE includes Prophase, Telophase, Anaphase, Metaphase? Put the Above-mentioned Phases in the correct Chronological Order. Warm-Up 11/16/10. Which organism has larger cells? - PowerPoint PPT Presentation

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Warm-Up 11/15/10• LIST the Phases of the Cell Cycle.

• Which Phase of the CELL CYCLE includes Prophase, Telophase, Anaphase, Metaphase?

• Put the Above-mentioned Phases in the correct Chronological Order.

Warm-Up 11/16/10• Which organism has larger cells?

• How does Size & Shape Affect how efficient a Cell is?

Warm-Up 11/16/10

• Identify the formula for the following:–Surface Area

–Volume

What are the metric units associated with each measurement?

• Identify the formula for the following:–Surface Area

• SA of Rectangle = 2(lw + lh + wh)

• Volume of Rectangle = L x W x H

• What are the metric units associated with each measurement?

– SA Ex: 2 [(2m x 2m) + (2m X 2m) + (2m x 2m)] = 24m2

– Volume Ex: 2m x 2m x 2m = 8m3

• What is the ratio of SA to Volume in the following example?

–SA Ex: 2 [(2m x 2m) + (2m X 2m) + (2m x 2m)] = 24m2

–Volume Ex: 2m x 2m x 2m = 8m3

–SA / Vol = 24m2 / 8m3 = 3 / 1

Warm-Up 11/17/10

• What is the purpose of the Cell Cycle?

• What are the Phases of Mitosis in chronological order?

Exit Ticket

• Identify the differences between the Cell Cycle and Mitosis.

Cell Growth and Reproduction

Section 10.2

CSII-H

Limits to cell growth

• DNA – can only control the needs of a small cell

• Cell Size - cell must have a low surface to volume ratio

• Cell Division – when a cell gets too large to control or function efficiently, cell division takes place

Cell Cycle

• Growth

• Nuclear division

• Cytoplasmic division.

Warm-up

• What are the 4 phases of mitosis?

– Prophase– Metaphase– Anaphase– Telophase

Interphase

• G1 – growth phase –> cell gets bigger and develops.

• S – synthesis phase –> DNA in nucleus is copied.

• G2 – growth phase –> more growing and developing; produce more organelles, enzymes, centrioles are replicated, etc.

Mitosis

• Nuclear division

• Yields 2 daughter nuclei that are genetically identical.

• Used for Growth and Healing.

Prophase• Chromatin condenses into

chromosomes, 2 identical strands of DNA attached by a centromere.

• Centrioles move to opposite ends of the cell.

• Nuclear envelope and nucleolus disappear.

• Spindle starts to appear.

Metaphase

• Chromosomes line up on Metaphase Plate between the centrioles.

• Spindle fibers attach to chromosomes at centromeres.

Anaphase• Centromeres are pulled apart

as spindle fibers contracts.• Chromatids (half of a

chromosome) are pulled in opposite directions.

• Chromatids are pulled to opposite ends of the cell.

Telophase

• Chromatids complete journey to the ends of the cell.

• Chromatin is formed as DNA elongates.

• Nuclear envelope forms around each set of DNA.

• Spindle disappears

• Nucleoli appear in each nucleus

Cytokinesis

• Cytoplasmic Division

• Begins during anaphase

• Furrow / ring starts to develop in the middle of the cell membrane

Cytokinesis

• In plants, you start to develop a cell plate

• Ring contracts until it completely separates the two new nuclei and about ½ organelles into each new cell

Control of the Cell Cycle

• Cyclins (proteins) regulate cell growth

• Internal regulators – only move to the next phase of the cell cycle when the previous phase is complete

Control of the Cell Cycle

• External regulators – if there is room, a cell divides; if neighboring cells are touching, cell growth is inhibited because space is scarce

Cancer

• Uncontrolled cell growth.

• Tumors are cells that do not respond to cell regulators.

• Results from a loss of regulation / control during the cell cycle.

Apoptosis

• Normal part of development for most cells in a multi-celled organism.

• Special enzymes will break cells down.