Download Asexual Reproduction

Name:_____________________________________________
Science 8 – Hagan
Date____________
Period____________
Page __
Asexual Reproduction
Essential Objectives:
1. I can explain the different types of asexual reproduction.
2. I can give examples of animals and plants that reproduce asexually
3. I can describe the advantages and disadvantages of reproducing asexually
TYPES OF ASEXUAL REPRODUCTION
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carried out by unicellular organisms, many lower animals, and many plants
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asexual reproduction IS mitosis
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offspring are identical to the parents
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the process is usually rapid and results in a large number of offspring
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there are several types of asexual reproduction
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Benefits: In a stable environment a large number of offspring can be produced in a short time.
Its quick, takes less energy and all the offspring are viable (can reproduce)!
Drawbacks: If the environment is unstable (think global warming or infectious diseases),
offspring will have the same limited genes as their parent. The lack of gene variety means
that offspring are more vulnerable to extinction!
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1. binary fission or “fission”
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the division of nuclear material and cytoplasm into 2 parts that are _________ resulting in
___ new organisms which are ________________ to each other
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basically is simple animal cell mitosis
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organism examples _______________________________________________
Drawing of binary fission:
2. budding
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in unicellular organisms
o
Different from binary fission because ______________________________________
___________________________________________________________________
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in multicellular organism
Examples: ________________________
Drawing of budding:
Name:_____________________________________________
Science 8 – Hagan
Date____________
Period____________
Page __
3. Sporulation / Spores
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spores are _____________________________________________________________
______________________________________________________________________
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spores are protected by ___________________________________________________
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Organisms that sporulate: _________________________________________
Drawing of sporangia and spores (sporulation):
4. regeneration
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of body parts
o

describe: ________________________________________________________
o
occurs in such animals as _____________________________________________
o
Humans “regenerate” by _______________________________________________
new organisms
o
describe: ____________________________________________________________
o
occurs in organisms like
___________________________________________________________________
o
Seas star - as long as a ray--one of the points--has some of the center piece, it can grow
into a whole new sea star!)
Drawing of sea star:
5. Cloning
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A clone
______________________________________________________________________
______________________________________________________________________
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The technique
______________________________________________________________________
______________________________________________________________________
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The new individual is genetically _____________________ to the organism from which the
cell was taken.
Name:_____________________________________________
Science 8 – Hagan
Date____________
Period____________

First animal cloned in 1952 were _______________________________________.
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In 1997, a ____________________ (animal type) was cloned and named
Page __
_________________ by a Scottish scientist named Ian Wilmut.
6. vegetative propagation
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Describe _____________________________________________________________
_____________________________________________________________________
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many different types
A) runners
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Describe_______________________________________________________________
______________________________________________________________________
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when it reaches a favorable spot (enough _____________, _____________...) it will grow
into a new individual
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ex. _________________________________, _____________________
B) cuttings
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a new plant grows from __________________________________________________
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ex. coleus, geraniums
C) bulbs
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bulbs bud from parent plants
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can grow into new individuals
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ex. onions, tulips, garlic
D) tubers
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_____________-like structures that grow ____________________ from the parent
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can form new ____________________ organisms if the conditions are right
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ex. _________________________________
E) grafting
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special tissues--called cambium (embryonic) tissues can be attached to a cutting of a parent
plant
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ex. seedless oranges

can artificially grow plants with different characteristics that are desirable!
Name:_____________________________________________
Science 8 – Hagan
Asexual Reproduction Jigsaw
Date____________
Period____________
Page __
Use the following information as well as the Green Life Science and the Miller and Levine
Biology textbooks to help you answer your part in the jigsaw notes.
What are the 6 types of asexual reproduction?
Binary fission, budding, spore formation, regeneration, vegetative propagation, and cloning.
Binary fission is the simplest form of asexual reproduction. The parent cell simply divides into two parts that
are about equal. Each of the new cells, called daughter cells, becomes a separate individual. The daughter cell
organisms are identical to each other. Each of the new offspring then grows to a normal size. Binary fission is
the usual method of reproduction of one-celled organisms including protozoa, bacteria, and many algae.
Budding is another type of asexual reproduction. New individuals develop as small growths or buds on the
surface of the parent organism. The new organism may break off and live independently or remain attached and
live as a colony. Budding is different from binary fission because the offspring and parent are not the same size;
there is an unequal division of cytoplasm. Yeast, hydra, sponges, and some worts reproduce by budding.
Spores are special cells that some individual organisms produce. A thick, tough outer coating that protects the
inner cell usually surrounds spores. When released by the parent, each spore may grow into a separate
individual. Fungi, algae, and protozoa can reproduce by spore formation.
Regeneration is the ability to re-grow lost body parts. Starfish or sea stars, earthworms, hydra, and planarian
(simple annelids or worms) can regenerate into new individual. A planarian that is cut into several pieces will
regenerate into several new worms. So long as a the ray of a sea star still has some part of the center attached,
it could grow back into an entire new sea star! Lobsters, crabs, and gecko lizards can regenerate new body parts
that may be lost. We do a form of regeneration when we grow new skin over a cut.
Vegetative propagation is new cells separating from the parent and forming a complete, independent
individual. Plants can reproduce asexually by vegetative propagation. Roots, stems, and leaves are called
vegetative structures. Some plants reproduce vegetative by special structures such as bulbs, corms, tubers,
runners, and rhizomes. Farmers and gardeners have taken advantage of different plants' ability to reproduce
asexually for generations. Artificial vegetative propagation allows gardeners and farmers to grow plant with
certain traits. A "cutting" is any vegetative part of the parent plant used to produce a new individual Runners
are stem-like structures that grow above the soil from the parent. When a runner reaches a favorable spot
(enough light, water...) it will grow into a new individual. Examples of plants that reproduce with runners are
strawberries and ivy. Tubers are underground, stem-like structures that expand to form enlarged structures.
These can grow into new, individual plants if the conditions are right that are identical to the parent. From one
tuber, many new plants can form. Example of a tuber would be potatoes and sweet potatoes.
Cloning is a scientifically-engineered reproductive technology that involves infusing the genetic material from
a parent organism in to an (nucleus removed) of another cell. See pg. 427 of LE Biology text