This presents how organisms self - replicate or reproduce.

1. reproduction

2. • Asexual • Sexual
Reproduction Reproduction
– involves only one – involves two
parent parents
– offspring is – offspring has
genetically identical genetic mix of both
to the parent parents
– involves regular – involves specialized
body cells sex cells
– quick – slow

3. Asexual Reproduction
• Binary Fission
– happens in bacteria, amoeba, and some algae
– one parent cell splits into two identical
daughter cells
• Budding
– happens in yeast, hydra, corals
– parent produces a bud
– bud gets detached and develops into
offspring which is identical to its parent

4. Binary Fission
Rod-shaped Bacterium,
Hemorrhagic E. coli
two daughter cells are identical to its parent

5. Budding

6. Asexual Reproduction
contd.
• Spore Formation
– happens in fungi, green algae, molds and
non-flowering plants (e.g. ferns)
– spores are produced and each spore develops
into offspring which are identical to its parent
• Vegetative Reproduction
– does not involve seeds
– some offspring can grow from cuttings (e.g.
coleus), runners (e.g. strawberries), tubers (e.g.
potatoes) or bulbs (e.g. tulips), which are part
of the parent plant

7. Spore Formation
Fern
Fungi

8. Vegetative
Reproduction

9. Sexual Reproduction in
Animals
• involves specialized sex cells called gametes
• the union of a male and a female gamete results
in the formation of a zygote that develops into a
new individual

10. Sexual
Reproduction in
Plants
Female Parts
Male Parts
(Pistil)
pollen (male) + ovule (female) → single-celled zygote → multi-celled
embryo (contained in a seed) → new individual

11. Sexual Reproduction in
Plants
• stamen is the male part and contains
pollen
• carpel or pistil is the female part and
contains ovule (eggs)
• pollen grains from the anther are
transferred to the stigma by the process of
pollination
– Self-pollination (plant pollinates its own eggs)
– Cross-pollination (pollen from one plant
pollinates another plant’s eggs)

12. Pollination
• flowers are designed to lure insects to help
with the pollination process
– wind, animals, birds can also transport pollen

13. Sexual Reproduction
Summary
Male Female Type of Result of Final
Gamete Gamete Union Union Result
Plants pollen ovule pollination single-cell multi-cell
(egg) zygote embryo
(in seed)
Animals sperm egg fertilization single-cell multi-cell
zygote embryo

14. Some Organisms Do Both
• most plants that produce seeds (sexual
reproduction) can also reproduce asexually
by things like cuttings or runners
• this gives them an advantage for survival
sponges and hydrae mosses

15. Which is Better?
It depends!
Asexual Reproduction Sexual Reproduction
• Advantages • Advantages
– does not require special – lots of variations within
cells or a lot of energy a species
– can produce offspring – able to live in a variety
quickly of environmental
– creates a large, thriving settings
population in a stable – able to adapt to
environment changes in the
• Disadvantages environment
– limited ability to adapt • Disadvantages
– face massive die-off if – needs time & energy
environment changes – produce small
populations