Aim: What is Asexual Reproduction? Do Now: On your paper Notes are in green.

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Aim: What is Asexual Aim: What is Asexual Reproduction?Reproduction?Do Now: On your paperDo Now: On your paper

Notes are in green

What Does “Asexual Reproduction” Mean?

•“A” means without.•“Sexual” refers to sex.•Therefore, Asexual

Reproduction means to reproduce WITHOUT SEX.

Weird But True . . . • It seems obvious . . . Sex and babies go

together. But many, many organisms make babies without sex!

• Some of these organisms reproduce without sex ALL of the time. Other organisms can reproduce either way!

• How do you think life would be different if humans could reproduce asexually? Write down at least two ideas.

What are these weird, nonsexual organisms?

• Some of them may be new to you…

What are these weird, nonsexual organisms?

• But some may be more familiar than you think…

Types of asexual reproduction

1. Binary Fission/Mitosis

2. Budding

3. Vegetative Propagation

4. Spore Formation

5. Regeneration

6. Parthenogenesis

Binary Fission• THE SAME AS mitosis. • In other words, cell division.

• http://video.google.com/videoplay?docid=1569716337466274469&q=binary+fission&total=18&start=0&num=10&so=0&type=search&plindex=0

Binary Fission from

the regents people

Budding• A small piece of an organism falls off and

forms a new organism• If you could do this, your finger could fall

off and become a baby. • Some organisms that do this: yeast, many

plants, fungi, hydra, coral

• http://video.google.com/videoplay?docid=-8082166555322930760&q=asexual+reproduction+budding&total=1&start=0&num=10&so=0&type=search&plindex=0

Budding from the regents

people

Vegetative Propagation• Cuttings of plants will develop roots when

placed in fertile soil

• Forms colonies of clones

• http://video.google.com/videoplay?docid=5302133060487001476&q=vegetative+propagation&total=1&start=0&num=10&so=0&type=search&plindex=0

Strawberries do this very easily!

Sporulation / Spore Formation

• “Spore” = a reproductive cell that develops without union with another cell

• Mushrooms reproduce this way.

• http://video.google.com/videoplay?docid=-6421882189540858078&q=spores+fungus&total=76&start=0&num=10&so=0&type=search&plindex=4

Sporulation from the regents

people

This is magnified MOLD, not a plant.

Regeneration

Planaria (free-living flatworm) capable of extreme examples of regeneration

If you cut an organism in half, both ends will form a new organism.

Sea stars also do this.

Parthenogenesis

• A female animal reproducing without mating with a male

The asexual, all-female whiptail species in the center, surrounded

by two species with males.

Sometimes, a species will ONLY reproduce through parthenogenesis, in which case a species will be ONLY female.

Aim: What is cellular Aim: What is cellular mitosis?mitosis?

Do Now: On your paperDo Now: On your paper

Cell Mitosis• Mitosis occurs all over the body

(except for the gonads.)

• Used for GROWTH and REPAIR.

• Occurs in STAGES.

Before we begin . . .

• Let’s imagine that you are moving apartments . . . What makes more sense?

Taking your stuff to your new apartment one thing at a time

Packing your stuff in boxes before you move it.

Before we begin . . .

• Your cell is faced with the same dilemma. If you stretched it all out, YOU HAVE OVER SIX FEET OF DNA IN EACH CELL. You need to get this WHOLE message into each new cell every single time.

• To do this, your cell packs the message into “boxes” … Known as “chromosomes.”

What is a chromosome?

• A chromosome is a bunch of DNA all twisted up.

• DNA does this in order to get ready for cell division. (Just like how you pack all of your stuff into boxes when you move from one apartment to another!)

A Chromosome

A Chromosome

A Chromosome

Mitosis Vocabulary

• Mitosis - process by which cells reproduce Also called Cell division or binary fission.

• Chromatid - one strand of DNA; after replication, a chromosome is made up of two identical chromatids

• Daughter cells - new cells produced by cell division

How can we remember the stages of mitosis?• Interphase

• Prophase

• Metaphase

• Anaphase

• Telophase

I Play Mario All the Time.

Stage One: Interphase

• Cell is NOT reproducing

• Growing and doing its normal job.

• During the end of interphase, DNA makes a copy of itself

or replicates.

Stage Two: Prophase

• Cell’s DNA condenses and forms visible chromosomes.

Stage Three: Metaphase

• Chromosomes MEET IN THE MIDDLE

Stage Four: Anaphase

• Chromosomes pull APART.

Stage Five: Telophase

• TWO daughter cells form

• Cells finish dividing.

Let’s Watch It!

One More Time!

• Are the two “daughter cells” created during mitosis identical to one another or different from each other? Why do you say so?

Brainpop- Mitosis

• http://www.brainpop.com/science/cellularlifeandgenetics/mitosis/

Aim: What is cancer, and Aim: What is cancer, and how is it related to how is it related to

mitosis?mitosis?Do Now: On your paperDo Now: On your paper

Notes are in hot pink!!

What is cancer?• Mouth cancer, just one type of many

cancers caused by smoking cigarettes.

What is cancer?

Cancer is uncontrolled mitosis.

What is cancer?

• Normal, healthy cells know when to divide and when not to. Your cells normally cooperate and do their jobs well, like law-abiding people in a city.

What is cancer?

• Cancer cells are like zombies. They are your own cells, but they aren’t helping you anymore!!

What is cancer?

• Cancer cells are selfish! Unlike your normal cells, they don’t do their jobs. They divide again and again, pushing the good cells out of the way!

What does this look like?

Two types of tumors

• Benign tumors do not spread from their site of origin, but can squash surrounding cells

• Malignant tumors spread from the original site and cause secondary tumors. This is called metastasis. They interfere with neighboring cells and can block blood vessels, the gut, glands, lungs, etc.

• Why is cancer so hard to treat? (HINT- DO CANCER CELLS INVADE US FROM THE OUTSIDE? OR ARE THEY PART OF US?)

• http://www.pbs.org/wgbh/nova/cancer/grow_flash.html

http://outreach.mcb.harvard.edu/animations/biochem.swf

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