Asexual ReproductionAsexual Reproduction

4.24.2

I. Asexual ReproductionI. Asexual Reproduction

A.A. Asexual ReproductionAsexual Reproduction- A new - A new organism is produced from organism is produced from one parentone parent

1. The new organism is 1. The new organism is identical to the parentidentical to the parent

I. Asexual ReproductionI. Asexual Reproduction

B. Types of Asexual ReproductionB. Types of Asexual Reproduction1. 1. FissionFission- Organism divides to - Organism divides to create an identical organismcreate an identical organism

a) DNA must be copied a) DNA must be copied firstfirst

b) Occurs in bacteria b) Occurs in bacteria (prokaryotes) (prokaryotes)

I. Asexual ReproductionI. Asexual Reproduction

2. 2. BuddingBudding-using cell division to -using cell division to grow a new organism from the grow a new organism from the body of the parentbody of the parent

b) When it is full grown b) When it is full grown the new organism breaks the new organism breaks

offoff

3. Ex: Hydra, Yeast3. Ex: Hydra, Yeast

I. Asexual ReproductionI. Asexual Reproduction

3. 3. Regeneration-Regeneration- Using cell Using cell division to regrow damaged or division to regrow damaged or lost body partslost body parts

a) Pieces of an organism a) Pieces of an organism can be used to grow an can be used to grow an entire organism.entire organism.b) Ex: Star fish, b) Ex: Star fish,

salamander salamander tails, tails, SpongebobSpongebob

I. Asexual ReproductionI. Asexual Reproduction

4. 4. Vegetative ReproductionVegetative Reproduction- A - A form of asexual reproduction form of asexual reproduction in which offspring grow from in which offspring grow from part of a parent plantpart of a parent plant

a) Ex: Stolons a) Ex: Stolons (strawberries (strawberries and and potatos)potatos)

I. Asexual ReproductionI. Asexual Reproduction

Yeast budding under Yeast budding under microscope. See launch lab microscope. See launch lab in resource bookin resource book

Use “Visualizing Cell Processes Use “Visualizing Cell Processes DVD to illustrate.DVD to illustrate.

--DNA Structure & Cell --DNA Structure & Cell reproductionreproduction

--Condensing --Condensing chromosomeschromosomes

--Stages of mitosis--Stages of mitosis

--Cytokenesis--Cytokenesis

II. Why DivideII. Why Divide

A. To replace dead cellsA. To replace dead cellsB. To grow B. To grow

1.# of new cells exceed the # of 1.# of new cells exceed the # of dying cellsdying cells

C. Limit cell sizeC. Limit cell size1. The smaller the cell, the more 1. The smaller the cell, the more efficient it gets nutrients and efficient it gets nutrients and gets rid of wastesgets rid of wastes

III. ChromosomesIII. Chromosomes

A. A. ChromosomesChromosomes- Cell structure - Cell structure that carries genetic materialthat carries genetic material

1. Composed of DNA wrapped 1. Composed of DNA wrapped around proteinsaround proteins

2. Appear right before cell 2. Appear right before cell division occurs (Condensed)division occurs (Condensed)

III. ChromosomesIII. Chromosomes

3. 2 3. 2 sister chromatidssister chromatids are held together by a are held together by a centromerecentromere

a. Each a. Each chromatid is identicalchromatid is identical

4. See video4. See video

IV. Cell CycleIV. Cell Cycle

A. OverviewA. Overview

1. Interphase1. Interphase

2. Mitosis2. Mitosis

3. Cytokenesis3. Cytokenesis

B. B. Cell CycleCell Cycle- Sequence of growth - Sequence of growth and division of a cell.and division of a cell.

III. Cell CycleIII. Cell Cycle

C. InterphaseC. Interphase

1. Rapid growth & metabolism1. Rapid growth & metabolism

2. DNA replication2. DNA replication

3. Centrioles replicate in 3. Centrioles replicate in preparation for cell divisionpreparation for cell division

III. Cell CycleIII. Cell Cycle

D. Mitosis (PMAT)D. Mitosis (PMAT)1. Prophase1. Prophase

a. Chromosomes a. Chromosomes condensecondenseb. Nuclear envelope and b. Nuclear envelope and nucleolus disintegratenucleolus disintegratec. c. Spindle fibersSpindle fibers form in form in

between between centriolescentrioles at opposite at opposite sides of the cell.sides of the cell.

III. Cell CycleIII. Cell Cycle

D. Mitosis (PMAT)D. Mitosis (PMAT)

2. Metaphase2. Metaphase

a. Spindle fibers attach a. Spindle fibers attach to centromeres of the to centromeres of the chromosomeschromosomes

b. Chromosomes are b. Chromosomes are pulled to the center of the cellpulled to the center of the cell

III. Cell CycleIII. Cell Cycle

D. Mitosis (PMAT)D. Mitosis (PMAT)

3. Anaphase3. Anaphase

a. The sister a. The sister chromatids are pulled apart to chromatids are pulled apart to opposite sides of the cell by opposite sides of the cell by the spindle fibersthe spindle fibers

III. Cell CycleIII. Cell Cycle

D. Mitosis (PMAT)D. Mitosis (PMAT)4. Telophase4. Telophase

a. Prophase in reverse!a. Prophase in reverse!b. The spindle fibers b. The spindle fibers

disintegratedisintegratec. The chromosomes c. The chromosomes

uncoiluncoil

III. Cell CycleIII. Cell Cycle

D. Mitosis (PMAT)D. Mitosis (PMAT)

4. Telophase4. Telophase

d. 2 new nuclear d. 2 new nuclear envelopes appear around the envelopes appear around the chromosomeschromosomes

5. Only the nucleus has 5. Only the nucleus has divided, not the entire celldivided, not the entire cell

III. Cell CycleIII. Cell Cycle

E. E. CytokenesisCytokenesis- The process in - The process in which the cytoplasm (cell) which the cytoplasm (cell) dividesdivides1. Animal cells pinch off to 1. Animal cells pinch off to form 2 new cellsform 2 new cells2. Plant cells form a cell plate 2. Plant cells form a cell plate then 2 new cell walls form on then 2 new cell walls form on either side of the plateeither side of the plate

III. Cell CycleIII. Cell Cycle

F. The two new cells go back to F. The two new cells go back to interphase to start the cycle interphase to start the cycle over again.over again.

G. Result: 2 Cells identical to G. Result: 2 Cells identical to each othereach other

RECAPRECAP

-Why do cells need to divide?-Why do cells need to divide?

-What are the stages of the cell -What are the stages of the cell cycle? What happens in cycle? What happens in each?each?

-What are the 4 phases of -What are the 4 phases of miosis? What happens in miosis? What happens in each?each?

RECAPRECAP

-What happens during -What happens during cytokenesis?cytokenesis?

-What do you start and end with -What do you start and end with at the beginning and end of at the beginning and end of the cell cycle?the cell cycle?

RECAPRECAP

-How many parents are involved -How many parents are involved in asexual reproduction?in asexual reproduction?

- Give an example of asexual - Give an example of asexual reproductionreproduction