Chapter 7
Section 2: Sexual vs Asexual Reproduction
Asexual Reproduction

Reproductive processes
that do not involve the
union of individuals or
gametes.
Asexual Reproduction
Occurs in most plants , bacteria, protists, and low
invertebrates.
 One parent!
 Offspring are identical to the parents.

Advantages of Asexual Reproduction
Easier to reproduce asexually!
 Requires less energy!
 Able to reproduce large numbers very
quickly in the right environment.

Disadvantages of Asexual Reproduction

Less genetic variation!
◦ Why is this bad?
 If there is a negative
genetic mutation in the
organism  all the
offspring will have this
mutation, which may be
disastrous.
Types of Asexual Reproduction

Regeneration –
organism uses cell
division to re-grow
body parts.
Types of Asexual Reproduction
Binary Fission – process
by which a parent
prokaryotic organism
(lacking a nucleus)
copies its DNA and
splits into two new
daughter cells.
 The daughter cells are
identical to their parent
cell.

Types of Asexual Reproduction
Budding – a form of
asexual reproduction that
a new organism develops
as an outgrowth or bud
from another organism.
 The bud stays attached to
the parent and continues
to grow until it reaches
maturity.
 Then pinches off.

Types of Asexual Reproduction
Vegetative Propagation is a form of asexual
reproduction in plants.
 Different types of vegetative propagation:

◦
◦
◦
◦
Runners
Tubers
Plantlets
Suckers
Types of Asexual Reproduction

Runners – stems which grow at the soil surface or
just below ground that form adventitious roots at
the nodes, and new plants from the buds.
Types of Asexual Reproduction
Tubers – plant
structures that are
used for nutrient
storage for winter and
dry periods.
 These structures can
develop into new
plants under certain
conditions.

Types of Asexual Reproduction

Cloning - is the process of
producing similar
populations of genetically
identical individuals that
occurs in nature when
organisms such as bacteria,
insects or plants reproduce
asexually.
Sexual Reproduction

Offspring are a
combination of both
parents therefore
different from each
parent.
Advantages of Sexual Reproduction
Variety and/or diversity of offspring (color, shape,
size, intelligence, ability, etc…)
 More able to adapt to environmental change.

Disadvantages of Sexual Reproduction
Sometimes traits needed
for survival are not
passed on.
 Energy must be
consumed.
 Much slower.
 Very few offspring are
produced at one time.
 Mutations can occur.

Sexual Reproduction in Plants
Pollination is the sexual reproduction of plants.
 Male gamete = pollen – produced in anther
 Female gamete = ovum – produced in ovary

Sexual Reproduction in Animals
Male gametes (sperm)
produced in the testes.
 Female gametes (ova)
produced in ovaries.
 After fertilization, a
zygote is produced.
 The zygote develops into
an embryo.
