3-4 Notes – Asexual Reproduction
What is Asexual Reproduction?
• It produces offspring from a ______________ parent without the joining of _________ and _________ .
• The offspring is genetically ________________ to the parent.
Advantages
• No ____________ or _____________ expended finding a ____________ .
• Less _________ to produce offspring.
• _________________ AND ________________ are genetically identical, so they are equally well-adapted to the
same _____________________ conditions.
Disadvantages
• Without _____ parents, there is not much ______________ ___________________ .
• Lack of genetic variation makes offspring more open to attack from ________________ and changes in the
___________________ .
• Harmful _____________________ will be passed to offspring.
Types of Asexual Reproduction
• __________________ reproduce asexually by _______ ______________ that does not involve _________ .
• __________________ reproduce asexually by _________ and _______ ______________ .
Fission
• ______________ , which have no nucleus, reproduce by a process
called ______________ , which produces two genetically identical
cells very rapidly.
Mitotic Cell Division
• Some single-celled ________________ reproduce by ____________ , followed by _______ ______________ .
• Produces 2 _______________ cells that are each an organism.
Budding
• Asexual reproduction in which a new organism forms ____ the ______________ organism
• The new organism, a _______ , forms by __________ and _______ ______________ , and eventually separates
from the parent
• Example:
– Some single-cell (___________) and multicellular eukaryotes (__________)
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Plant Cuttings
• If you cut a green stem from a houseplant and put it in water, _________ and _____________ can grow, producing
a new plant.
• Some _________ propagate themselves asexually.
• Examples
– ___________________ plants and kalanchoe plants
Animal Regeneration
• Some animals have cells that can ____________ into other cell types.
• _________________ is asexual reproduction that produces new animals from __________ of an animal’s body.
• Regeneration is sometimes used to describe growth that _____________ a missing part of an animal.
Cloning
• ________________ refers to a method of asexual reproduction developed by ________________ and performed in
__________________ .
• Cloning produces ____________ individuals from a cell or cells taken from a ___________________ organism.
Animal Cloning
• The first animal to be successfully cloned was a __________ named ___________ , in 1996.
• Animals cloned in labs are usually not _______________ .
Review
____ 1.
What type of asexual reproduction involves reproduction by cell division only?
A. fission
C. regeneration
B. budding
D. cloning
____ 2.
What type of asexual reproduction involves a new organism forming on the parent organism?
A. mitotic cell division
C. regeneration
B. cloning
D. budding
____ 3.
What type of asexual reproduction involves producing a new animal from pieces of an animal’s body?
A. plant cuttings
C. regeneration
B. cloning
D. budding
____ 4.
What is not an advantage of asexual reproduction?
A. organism does not have to spend time and energy finding a mate
B. can produce a number of offspring faster than with sexual reproduction
C. offspring have more genetic variation
D. parent and offspring are equally well adapted to the same environmental conditions
____ 5.
What type of organism can reproduce asexually by regeneration?
A. human
C. bacterium
B. sea star
D. yeast
3-4 Notes – Asexual Reproduction
What is Asexual Reproduction?
• It produces offspring from a single parent without the joining of sperm and egg.
• The offspring is genetically identical to the parent.
Advantages
• No time or energy expended finding a mate.
• Less time to produce offspring.
• Parent AND offspring are genetically identical, so they are equally well-adapted to the same environmental
conditions.
Disadvantages
• Without 2 parents, there is not much genetic variation.
• Lack of genetic variation makes offspring more open to attack from disease and changes in the environment.
• Harmful mutations will be passed to offspring.
Types of Asexual Reproduction
• Prokaryotes reproduce asexually by cell division that does not involve mitosis.
• Eukaryotes reproduce asexually by mitosis and cell division.
Fission
• Bacteria, which have no nucleus, reproduce by a process called
fission, which produces two genetically identical cells very rapidly.
Mitotic Cell Division
• Some single-celled eukaryotes reproduce by mitosis, followed by
cell division.
• Produces 2 identical cells that are each an organism.
Budding
• Asexual reproduction in which a new organism forms on the parent organism
• The new organism, a bud, forms by mitosis and cell division, and eventually separates from the parent
• Example:
– Some single-cell (yeast) and multicellular eukaryotes (hydra)
Plant Cuttings
• If you cut a green stem from a houseplant and put it in water, roots and leaves can grow, producing a new plant.
• Some plants propagate themselves asexually.
• Examples
– Strawberry plants and kalanchoe plants
Animal Regeneration
• Some animals have cells that can change into other cell types.
• Regeneration is asexual reproduction that produces new animals from pieces of an animal’s body.
• Regeneration is sometimes used to describe growth that replaces a missing part of an animal.
Cloning
• Cloning refers to a method of asexual reproduction developed by scientists and performed in laboratories.
• Cloning produces identical individuals from a cell or cells taken from a multicellular organism.
Animal Cloning
• The first animal to be successfully cloned was a sheep named Dolly, in 1996.
• Animals cloned in labs are usually not healthy.
Review (Answers: 1-A, 2-D, 3-C, 4-C, 5-B)
____ 1.
What type of asexual reproduction involves reproduction by cell division only?
A. fission
B. budding
C. regeneration
D. cloning
____ 2.
What type of asexual reproduction involves a new organism forming on the parent organism?
A. mitotic cell division
B. cloning
C. regeneration
D. budding
____ 3.
What type of asexual reproduction involves producing a new animal from pieces of an animal’s body?
A. plant cuttings
B. cloning
C. regeneration
D. budding
____ 4.
What is not an advantage of asexual reproduction?
A. organism does not have to spend time and energy finding a mate
B. can produce a number of offspring faster than with sexual reproduction
C. offspring have more genetic variation
D. parent and offspring are equally well adapted to the same environmental conditions
____ 5.
What type of organism can reproduce asexually by regeneration?
A. human
B. sea star
C. bacterium
D. yeast