Meiosis is a type of cell division that produces gametes, or sex cells, with half the number of chromosomes as the original parent cell. It involves two rounds of division called Meiosis I and Meiosis II. In Meiosis I, the parent cell undergoes DNA replication followed by one round of division, resulting in two daughter cells each with half the number of chromosomes. Meiosis II involves a second round of division without DNA replication, resulting in four daughter cells total, each with half the number of chromosomes as the original parent cell. This ensures genetic variation in offspring and the normal chromosome number is maintained. Errors during meiosis can result in chromosome number abnormalities.
2. LEARNING OBJECTIVES
• Define meiosis.
• Explain the importance of meiosis.
• Identify the phases of meiosis and its characteristics.
• The differences between mitosis and meiosis
• Accidents in meiosis
3. WHAT IS MEIOSIS ?
•Meiosis is a type of cell division which is
important for sexual reproduction.
• A single cell divides twice to produce four cells
containing half the original amount of genetic
information. These cells are our sex cells –
sperm in males, eggs in females.
•These four daughter cells only have half the
4. THE IMPORTANCE OF MEIOSIS
•Meiosis halves the number of chromosomes
going to sex cells so that the offspring will
have both the mother and father’s genetic
material.
•Meiosis reduces the chromosome number so
that the offspring will be normal.
•It brings about variation of off springs or
6. TWO STAGES OF MEIOSIS
• MEIOSIS l is divided into five phases. It begins with one diploid
parent cell and ends with two haploid daughter cells, halving
the number of chromosomes in each cell.
• Meiosis ll is divided into four phases. Meiosis II starts with two
haploid parent cells and ends with four haploid daughter cells,
maintaining the number of chromosomes in each cell.
7. PHASES OF MEIOSIS I
• Interphase I
• Prophase I
• Metaphase I
• Anaphase I
• Telophase I
8. PHASES OF MEIOSIS II
• Prophase II
• Metaphase II
• Anaphase II
• Telophase II
11. IMPACTS OF ACCIDENTS DURING MEIOSIS
•Non-disjunction is a failure of chromosome or
chromatids to separate normally during
meiosis.
•Meiosis I- when all homologous pairs goes to
one pole.
•Meiosis II- when both sister chromatids goes to
one pole.
12. REFERENCE LIST
Chris, P., 2015. Knowledge presentation on meiosis. [Online]
Available at: https://bioknowledge.weebly.com
[Accessed 18 September 2017].
Farrellw, 2012. Education, Technology.. [Online]
Available at: https://www.slideshare.net/farrellw/mitosis-powerpoint-11179257
[Accessed 18 september 2017].
Hernaez, H. A., 2012. mitosis and meiosis. [Online]
Available at: https://www.slideshare.net/SHEYngLe/mitosis-and-meiosis-11942775
[Accessed 18 September 2017].
Jaycris, A., 2010. sciencephotolibrary. [Online]
Available at: https//:www.slideshare.net/mobile/JayicsAgnes
[Accessed 18 september 2017].
Peterson, C., 2008. Science instructor, Biology and Science-environmental science at lowel school,
Bisbee, AZ.. [Online]
Available at: https://www.slideshare.net/catherinepatterson/cell-division-mitosis-and-meiosis-
presentation?qid=7cc83109-6a52-46bd-8a07-8274975d6cdc&v=&b=&from_search=1
[Accessed 18 September 2017].