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There are two types of reproduction. Sexual and Asexual. To really understand what those words mean lets break them apart.

Asexual reproduction

Asexual is easy to break apart. The prefix “A” comes from the Greek language and means "without". "Sex" means "to cross." Thus the term asexual means "without to cross" which really doesn't make sense but it is also defined as without crossing. Asexual organisms make exact copies of themselves, almost like a photocopy.  This photocopy is almost identical but mistakes can happen that allow different traits to occur in the copy. One of the big differences is the copy is usually a little smaller especially in larger organisms that reproduce this way. Some examples of organisms that reproduce asexually are:

Amoeba
Bacteria
Hydra
Paramecium
 
Lindens, like many trees can reproduce asexually through a process called propagation. Propagation means that humans cut a part of the tree off and plant it so that it grows roots and begins a new tree. Certain trees like navel oranges which have no seeds can only reproduce this way.


Sexual reproduction

We already know that asexual means without crossing or only one parent. Sexual means “to cross.” Sexual reproduction means that two parents combine parts of their genetic material. With sexual reproduction there is usually a male and a female. The male contributes a copy of half of his genetic material that is combined with half of the genetic material contributed by the female. The “baby” that is born is called the offspring. In a very basic way, offspring get half of their traits from each parent. Because of the way the males and females copy their own genetic material and the way they are combined, each offspring is different. It is a little like rolling dice for each offspring. Some animals that reproduce sexually are:

bee
beetle
chipmunk
ferret
lizard
mallards
petunia
seal
toad
turkey

 

 
Both

Many plants and animals are adapted to reproduce both ways. There are advantages to each method. Jellyfish are an example of an animal that can reproduce both ways. They reproduce sexually but they also reproduce asexually. The asexual way allows them to make many copies of themselves that have an easier time finding a mate than one copy would. The sexually reproducing copies can then find a mate and produce offspring with different traits. These different traits may give the offspring an advantage that the parents didn’t have. Other organisms which may reproduce using both asexual and sexual reproduction include:
 

 


Daffodil
Cactus
Mushroom
Sponge
Starfish


Analysis:

Use a diagram like the circles below to compare and contrast sexual and asexual reproduction. List characteristics about sexual reproduction in the right circle and characteristics of asexual reproduction in the left circle. Where the two circles overlap put characteristics that the two types of reproduction have in common.

  1. What advantages are there to sexual reproduction?
  2. What advantages are there to asexual reproduction?
  3. What would you say is the most important difference between the the two types of reproduction?

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Updated August 9, 2006 by: Glen Westbroek

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