Transcript Sexual Reproduction

Reproduction
L/O :- To know the difference between
sexual reproduction and asexual
reproduction
Do plants have sex?
Sexual reproduction is sometimes
referred to as sex. Some plants
reproduce sexually so ‘how do plants
have sex?’
Are all plant offspring (babies) exactly the
same as the parent plants?
What are the differences between
sexual and asexual reproduction?
Asexual Reproduction
Sexual Reproduction
Asexual Reproduction
Sexual Reproduction
• Involves only 1 parent
• Organisms are identical
and called clones
• Their genes are identical
• Involves 2 parents
• Half the genetic
information is received
from each parent
• Offspring inherit a
mixture of alleles from
different parents so
don’t look the same
• Produces offspring that
resemble both parents,
but are not identical to
them
Examples:
Daffodils, Strawberries,
Brambles, Spider Plants,
Bacteria
Sexual Reproduction
In asexual reproduction all
the chromosomes are
copied to form a CLONE.
BUT in sexual
reproduction, half
the chromosomes
come from each
parent and. Each
chromosome carries
the same genes but
these may be
different versions
(alleles)
Explain how sexual and asexual
reproduction happens (6 marks)
You will be given marks for your use of English
What does this
mean about the
GAMETES (sex
cells)?
Sexual Reproduction
Male gamete and a female gamete join - this fusion of
gametes is called fertilisation

Allows some of the genetic information from each
parent to mix, producing offspring that resemble their
parents, but are not identical to them


In this way, sexual
reproduction
leads to variety in
the offspring



Each pair of genes affects a different characteristic –
the genes in the pair can come in different forms
These different versions of the same gene are called
alleles
Offspring inherit a random mixture of thousands of
alleles from their parents, which is why offspring do
not look exactly like either parent
Asexual reproduction


Only needs one parent, unlike sexual reproduction,
which needs two parent
Since there is only one parent, there is no fusion of
gametes and no mixing of genetic information – So
the offspring are genetically identical to the parent
and to each other (clones)


Some plants produce side branches
with plantlets on them (e.g. Busy
Lizzy)
Other plants produce runners with
plantlets on them (e.g. strawberries)

Asexual reproduction in plants can take a number of
forms Many plants develop underground food storage
organs that later develop into the following year’s
plants (e.g. potato plants and daffodil plants)
Daffodil bulb at start of
season
Daffodil bulb at end of
season
Speedy bacterial clones
Bacteria can copy themselves very quickly – their numbers
can double every 20 minutes! That’s 10 times faster than
the quickest animal cells.