Download Unit 4 – Cellular Reproduction Meiosis Notes Name: Number

Unit 4 – Cellular Reproduction
Meiosis Notes
Name:
Number:
Asexual Reproduction:
 Advantages
o It is faster
o Large numbers of offspring are produced.
o The parent does not have to find a mate.
 Disadvantages
o All of the offspring are exactly alike.
o There is no ____________.
o The ability to adapt to a changing environment is greatly reduced.
Sexual Reproduction:
 Advantages
o All of the offspring are genetically ___________ from each other.
 Disadvantages
o The parent must find a mate.
o Fewer offspring will be produced.
o It takes longer.
Cell Division and Chromosome Number:

Homologous chromosomes
o Two copies of each chromosome, one coming from the mother and one coming
from the father.
o Carry the same genes, but they may have different expressions of that gene.

Haploid –

Diploid –
Meiosis occurs in 2 stages:
 Meiosis I
1. Interphase
2. Prophase I
3. Metaphase I
4. Anaphase I
 Meiosis II
5. Telophase I
6. Prophase II
7. Metaphase II
8. Anaphase II
9. Telphase II
Importance of Meiosis:



“Crossing over” is the exchange of _________________ between segments of
homologous chromosomes during meiosis.
The result is that the offspring will receive ______________ of genetic information. This
leads to ________ in the offspring.
Meiosis produces _____________ cells that are different.
Unit 4 – Cellular Reproduction
Meiosis Notes
Comparison of Mitosis and Meiosis:
 Mitosis occurs in all cells of the ______ except ________________. Meiosis only occurs in
the formation of _______________________.
 In meiosis, each __________ cell divides _______ to produce a total of _______ cells. In
mitosis each _________ cell divides ________ to form _____ cells.
 In meiosis, each of the four cells contains _______ the number of chromosomes as the
parent cell. In mitosis, each new cell contains the _______ number of chromosomes as
the original cell.
 In mitosis, the homologous pairs do not come together to form ___________. In meiosis,
the homologous pairs do come together to form __________. While the chromosomes
are in tetrads, __________________ may occur. There will be no crossing over in
________________.

In meiosis, the four haploid cells contain _______________ combinations of
chromosomes from each other. In mitosis, the new cells contain _____________ copies.