Name _________________________________________________ Hour___________
In the next chapter we will be learning about a process called meiosis. Meiosis is the process that
leads to the development of gametes (sex cells; such as sperm and eggs) in sexually reproducing organisms.
Gametes have half the number of chromosomes as the original parent cell. Along with Mendel’s laws of
segregation and independent assortment, meiosis can lead to genetic variation. Genetic variation is why
none of us look alike and vary “genetically”.
Not every organism reproduces sexually however. There are many organisms that reproduce
asexually by cloning themselves. In asexual reproduction, one individual produces offspring that are
genetically identical to itself. These offspring are produced by mitosis. There are many invertebrates,
including sea stars and sea anemones for example, that produce by asexual reproduction. In some cases
even complex organisms can undergo asexual reproduction in a process called parthenogenesis. Animals
like most kinds of wasps, bees, and ants that have no sex chromosomes reproduce by this process. Some
reptiles and fish are also capable of reproducing in this manner.
1. From the reading above, what would you say is a main difference between mitosis and meiosis?
2. Why do you think that your gametes have half the number of chromosomes as the original parent
cell? (Ex: Your body cells have 46 chromosomes, but your gametes have 23 chromosomes).
3. There are advantages and disadvantages to both types of reproduction: sexual and asexual. Please
take the time to really think outside of the box!
a. Describe why the genetic variation created during meiosis and sexual reproduction might be
advantageous. Several sentences.
b. Describe how asexual reproduction, like cloning, in organisms might be advantageous.
Several sentences.