2 sister chromatids Chromosomes OR Chromatids ReplicationAnaphase 1 Chromosome Interphase 2...

2 sister chromatids

Chromosomes OR Chromatids

ReplicationAnaphase

1 Chromosome

Interphase

2 identical Chromosome2 identical chromatids

One in each daughter cell.

Prophase

Interphase Prophase Metaphase

Parent cell Visible but not organized

Chromosomes lining up

Anaphase Telophase Interphase

Pulling apart Cell dividing Two identical cells

X marks the spot

Reproduction and Cell Division

The modern cell theory states that• All living things are made of one or more cells• The cell is the functional unit of life• All cells come from preexisting cells

There are 2 types of organism reproductionAsexual and Sexual

• Differentiate among the various methods of asexual reproduction

• Identify the different types of asexual reproduction

KEY WORDS

Asexual ReproductionBinary FissionBudding SporulationRegenerate Vegetative propagation

Asexual Reproduction

• Cell duplication using mitosis* and cytokinesis • Produces genetically identical cells.

1.Cells are “clones” - exact copy of original. 2. Rapid and effective method of reproduction. 3. No cellular diversity.

Various Types of Asexual Reproduction

Bacteria:

• Single-cell organisms (Unicellular).• Do not have a true nucleus. • Asexual reproduction called binary fission.• Example - E. coli (Escherichia Coli)

- organism splits into two equal sized cells each with chromosome of complete DNA.

Protists

• Unicellular organisms (with a nucleus). • Reproduce using standard mitosis. • Example - Ameoba

Fungi (1)

• Cell duplicates nucleus, forms outgrowth.• Asexual reproduction called Budding.• New cell is not the same size as original cell.

Unequal division of cytoplasm • Example – yeast

Standard mitosis Budding

Fungi (2)

• Large number of small spores formed by mitosis*• Spores released.• Form new organism when conditions are good.• Asexual reproduction called Sporulation.• Example – mould

Plants

• New organism created from roots, stems, leaves.• Asexual reproduction called Propagation • Example – strawberry plants (runners)

Animals

• Split into two big groups:Vertebrates (with backbones) Invertebrates (without backbones)

• Invertebrates will usually reproduce asexually.• Fragmentation – ability of an animal to

regenerate (regrow) parts of the body.

The simpler the animal, the greater the ability to regenerate.

Asexual reproduction - advantages.

• Easy to reproduce – even if you can’t move (stationary).• No need to find a partner.• Each cell will look and function the same – no variation.

Asexual reproduction - disadvantages.

• Can lead to overcrowding (and competition).• One disease can wipe out a whole species – no variation.• No possibility for adaptation and evolution.