Title: Cell%20Reproduction
1Cell Reproduction
2http//biotech-adventure.okstate.edu/low/basics/mi
tosis/mitosis-diagram/diagram.gif
3Cell Cycle
http//www.bmb.psu.edu/courses/biotc489/notes/cycl
e.jpg
4Mitosis
- One type of cell division
Cell process in which the nucleus divides to form
two nuclei identical to each other, and identical
to the original nucleus, in a series of steps
(prophase, metaphase, anaphase, and telophase)
5Mitosis allows for growth and replaces worn out
or damaged cells.
6Interphase
- Period of growth development
- Hereditary information (DNA) copied (replicated /
duplicated) - Cells that do not divide (nerves) are always in
interphase
7http//biotech-adventure.okstate.edu/low/basics/mi
tosis/phases/interphase/interphase.gif
8Prophase
- DNA begins to shorten thicken
- Now called chromatids / chromosomes
- Centromeres form
- Nuclear membrane breaks apart
- Spindle fibers form
9http//biotech-adventure.okstate.edu/low/basics/mi
tosis/phases/prophase/prophase.gif
10Metaphase
- Chromatids / chromosomes line up
- Centromere attaches to spindle fibers
11http//biotech-adventure.okstate.edu/low/basics/mi
tosis/phases/metaphase/metaphase.gif
12Anaphase
- Centromeres divide
- Spindle fibers shorten
- Chromatid pairs separate move to ends of cell
- Chromatids are now called
- Each ½ of the pair is now called a chromosome
13http//biotech-adventure.okstate.edu/low/basics/mi
tosis/phases/anaphase/anaphase.gif
14Telophase
- Spindle fibers disappear
- Chromosomes uncoil
- Nuclear membrane forms
- Cell divides (cytokinesis)
15http//biotech-adventure.okstate.edu/low/basics/mi
tosis/phases/telophase/telophase.gif
16Interphase Prophase
Metaphase Anaphase
Telophase Interphase
http//biology.nebrwesleyan.edu/benham/mitosis/
17Results of Mitosis
- Division of nucleus
- Nuclei are identical to each other
- Same number type of chromosomes
18Asexual Reproduction
- A type of reproduction - fission, budding, and
regeneration - in which a new organism is
produced from one parent and has DNA identical to
the parent organism.
19Asexual Reproduction
- Offspring produced from one organism
- Hereditary information is identical
- Mitosis is one form of asexual reproduction
20Sexual Reproduction
21Sexual Reproduction
- A type of reproduction in which two sex cells,
usually an egg and a sperm, join to form a
zygote, which will develop into a new organism
with a unique identity.
22Sexual reproduction results in a great variety,
or diversity, of offspring.
23Meiosis
- The nucleus divides twice
- Meiosis I
- Meiosis II
24Interphase
25Prophase I
- DNA shorten thicken
- Forms chromatids / chromosomes
26http//biotech-adventure.okstate.edu/low/basics/me
iosis/phases/prophase/leptotene/leptotene.gif
27Metaphase I
- Copied chromatids / chromosomes line up in middle
of cell - Centromeres attach to spindle fibers
28http//biotech-adventure.okstate.edu/low/basics/me
iosis/phases/metaphase-I/metaphase-I.gif
29Anaphase I
- Chromatid pairs are pulled apart
- They DO NOT separate
- Move to ends of cell
30http//biotech-adventure.okstate.edu/low/basics/me
iosis/phases/anaphase-I/anaphase-i.gif
31Telophase I
- Cell divides
- No further replication of hereditary material
32http//biotech-adventure.okstate.edu/low/basics/me
iosis/phases/telophase-I/telophase-I.gif
33There are now two cells. Both cells have full
sets of genetic material (chromosomes)
34Prophase II
- Similar to mitosis
- Starts with TWO cells instead of one
- Spindle fibers appear
35http//biotech-adventure.okstate.edu/low/basics/me
iosis/phases/prophase-II/prophase-II.gif
36Metaphase II
- Duplicated chromatid / chromosomes line up in
middle of cell - Spindle fibers attach to centromeres
37http//biotech-adventure.okstate.edu/low/basics/me
iosis/phases/metaphase-II/metaphase-II.gif
38Anaphase II
- Centromere divides
- Chromatids separate move to ends of cell
- Chromatids are now individual chromosomes
39http//biotech-adventure.okstate.edu/low/basics/me
iosis/phases/anaphase-II/anaphase-II.gif
40Telophase II
- Spindle fibers disappear
- Nuclear membranes form at each end of cell
- Cells divide
- Results in 4 cells
- Each with ½ the original number of chromosomes
41http//biotech-adventure.okstate.edu/low/basics/me
iosis/phases/telophase-II/telophase-II.gif
42In summaryMeiosis
- Two cells form during meiosis I
- In meiosis II, both of these cells form two cells
- The two divisions of the nucleus result in four
sex cells (gametes) - Each has one-half the number of chromosomes in
its nucleus that was in the original nucleus
43Differences in Mitosis Meiosis
- Mitosis
- Asexual
- Cell divides once
- Two daughter cells
- Genetic information is identical
- Meiosis
- Sexual
- Cell divides twice
- Four haploid daughter cells
- Genetic information is different