What are the different types of reproduction ? how they take place?

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Reproduction means to reproduce. It is a biological process by which an organism reproduces an offspring who is biologically similar to the organism. Reproduction enables and ensures the continuity of species, generation after generation. It is the main feature of life on earth
1. Notes: Types of Reproduction
***Key Idea: Genetic information is passed from
parents to offspring through CHROMOSOMES.
We have to get the chromosomes from the
parent cell the new cells that are being
2. In ASEXUAL reproduction, ONE organism divides in
two and makes an EXACT COPY of itself. This is
essentially MITOSIS.
Ex. Budding in yeast
Ex. Amoebas
Pros : NO ENERGY used to get together with
another organism.
Cons  : Only ONE parent contributes genes.
5. Sexual Reproduction: Meiosis
In SEXUAL reproduction, TWO organisms must
come together to create an offspring that is
genetically DIFFERENT than either parent.
Pros  : Genes from BOTH parents contribute to
Cons : Must USE ENERGY to get together with
another organism.
6. To reproduce sexually, the organisms must first form
“gametes.” Cells of the body have two copies of sets of
chromosomes. Gametes only have one set. Why?
DIPLOID cells have two sets of chromosomes. We
represent this as 2n.
HAPLOID cells have one set of chromosomes. We
represent this as n.
8. In humans, the MALE gamete is the SPERM.
The FEMALE gamete is the EGG.
The sperm swims up the female reproductive tract and
The egg and sperm together is called a ZYGOTE
The ZYGOTE then divides by MITOSIS to form a multicellular
(many-celled) organism. Mitosis is just plain old cell
9. Egg and Sperm!
12. The process of forming a gamete is called
Steps of Meiosis
1) Replication
2) Pairing up of homologous chromosomes.
3) First division
4) Second division
13. Mitosis Meiosis
Cell divides
once. You get
two cells
identical to the
original. Each
have two
copies of each
Two cell divisions. You get four cells
that are genetically different than
the original cell. Each have one
copy of each chromosome.
14. 2) Pairing up of homologous chromosomes.
o Ex. Both copies of chromosome 12
o ***Genetic material is exchanged or shuffled between
the homologous chromosomes in a process called
CROSSING OVER. This produces the NEW
combinations of traits that were not seen in either
15. Homologous Chromosomes
16. Homologous Chromosomes
Crossing Over!
17. 3) First division- Result is two haploid cells with
replicated chromosomes.
18. 4) Second division- Result is 4 haploid cells with
unreplicated chromosomes. (Result is the egg
or sperm).
19. Mitosis Meiosis
(asexual) (sexual)
# of divisions 1 2
# of cells produced 2 4
sets of chromosomes in 2 (cells are 1 (cells are haploid or
cells produced diploid or 2n) “n”)
type of cells it occurs all cells reproductive tissues
in only
homologous no yes
chromosomes pair up?
genetic variety of same as parent genes are shuffled
offspring cell during crossing over,