Transcript Asexual Reproduction

Title your page:
Sexual vs. Asexual
Reproduction Notes
Purpose of Reproduction
• To make sure a species can continue.
• Reproduction - the process by which an
organism produces others of its same kind.
Use the whole rest of the page to draw this chart.
Write in
margin
Sexual Reproduction
Asexual Reproduction
A= Not
Number of
Parents
Picture
with explanation
Offspring looks
like…
Genetic
Diversity?
Time to
reproduce
Examples
You will then use the following slides to fill in notes on each section in the chart.
Write small so that all the information will fit.
Sexual Reproduction (write in chart)
• Requires 2 parents: two sex cells (egg and
sperm) that require fertilization
Egg
Picture
Offspring
Sperm
The egg and sperm join to
form an entirely new
organism with traits of both
parents
• Offspring look genetically different from the
parent organism due to mixing of DNA
• The advantage is that genetic diversity allows
a variation in traits and enables a species to
be more able to adapt to environmental
changes
Time required to sexually reproduce
Reproduces slowly (ranges from a few to many months)
since the organism’s DNA is more complex that an
organism that uses Asexual reproduction
Examples of Sexual Reproduction
• Mammals such as humans, gorillas,
elephants, rats, zebras, and dolphins
• Flowers that contain a pistil (female
part) and stamen (male part) also
There MUST be a male and female parent for an
organism to sexually reproduce.
Draw this picture and label the
pistil and stamen
Read the following slide. Then on the next page in your notes (after your chart),
write the title and summarize the difference between internal and external
fertilization.
Sexual Reproduction: Internal vs. External Fertilization
Internal Fertilization
•
•
Fertilization occurs within the female.
Internal fertilization occurs in
mammals, insects, birds, reptiles.
– Mammals (gorillas, lions,
elephants, rats, zebras, and
dolphins have live births)
– Insects, birds, reptiles lay eggs
•
•
External Fertilization
External fertilization usually requires a
medium such as water, which the
sperms can use to swim towards the
egg cell. External fertilization usually
occur in fish and amphibians.
The females lay the eggs in the water
and the male squirts the sperm in the
same area.
Asexual Reproduction (write in chart)
• A new organism (sometimes more than one) is produced from
one organism.
Offspring
Offspring
Offspring
Parent
One parent produces
uniform offspring that are
Offspring an exact copy as the parent
(same DNA).
• The offspring will have hereditary material uniform with the
hereditary material of the parent organism. This means they will
be genetically identical.
• Asexually reproduced organisms cannot develop much variety
(no genetic diversity), because they are “copying” the original
organism exactly.
• Asexual Reproduction happens quickly causing rapid population
growth
Types of Asexual Reproduction
•
•
•
•
•
•
Budding
Vegetative Reproduction
Fragmentation
Regeneration
Spores
Fission (Binary fission)
Only write the types in the box on your chart. On the next page in your notes,
you will describe each type in detail.
Sexual vs. Asexual Reproduction Notes continued
Sexual Reproduction: Internal vs. External Fertilization
(your summary should be written here)
Types of Asexual Reproduction
Type of Asexual
Reproduction
Budding
Definition
Picture with
examples
Budding
• Process by which a new, duplicate
plant or animal begins to form at the
side of the parent and enlarges until
an individual is created.
• Very common in plants.
Hydra
offspring
Yeast
Cactus
Vegetative Reproduction
• Form of asexual reproduction in
plants where parts of the plant fall
off and develop into new plants
without seeds or spores.
• Examples: potato tubers, tulips,
strawberry, blackberry
Fragmentation
• When a plant is broken in 2 or more pieces,
and each one grows into a new individual.
• Lichens, Airplane Plant
Amoeba
Lichen
Airplane Plant
Regeneration
• The ability to restore lost or damaged tissues,
organs or limbs.
• It is a common feature in invertebrates, like
starfish.
Spores
• Uni-cellular bodies formed by the parent organism
to carry out reproduction. If environmental
conditions are suitable, the spore will develop into
an individual.
• Most common in fungi.
Fission (Binary Fission)
• A type of cell division in which
one cell divides into identical
cells.
• Examples: Paramecium,
Amoeba, Euglena
IMPORTANT!
• Asexual reproduction results in offspring that
are genetically identical to the parent
organism.
• Sexual reproduction results in offspring that
are genetically different from the parent
organisms.