Topic 6.6- 6.8: Reproduction and Meiosis Flashcards
What type of cells does meiosis produce
gametes
How many chromosomes are there in a normal cell
46 in total
What is the second stage of meiosis
all the chromosomes line up along the centre of the cell randomly placed
What is the first stage of meiosis
To replicate all of the DNA in the cell by adding an extra arm to each chromosome forming an x shape
What is the third stage of meiosis
The chromosomes are pulled to either end of the cell and then the cell divides, the chromosomes on each side are random so it produces genetically unidentical daughter cells
In meiosis are the daughter cell geneticlly identical or not
They are NOT genetically identical
What happens in the second division of meiosis
the chromosomes line up on the centre but the arms of each chromosome are pulled to either pole and then the cell divides
How many daughter cells does meiosis produce
4
During Meiosis how many times does the cell divide
2
What is sexual reproduction
the fusion of male and female gmetes (fertalisation)
and it produces genetically different offspring
Match sexual and aesuxual reproduction to mieosis and mitosis
sexual->Mieosis produces the gametes
Aesexual-> Mitosis
What is Aesxual reproduction
the replication of bacteria cells by mitosis for eukaryotic organisms and by binary fission for prokaryotic that produces genetically identical offspring (clones)
What are the advantage of aesexual reproduction
- Only one parent is needed
- process is very quick
What are the disadvantages of aesexual reproduction
- All offspring are clones so more likely to be wiped out by disease
-All offspring are clones meaning theres less chance of adaptation to new environments
What are the advantages of sexual reproduction
- Lots of genetic variation within the population
-> less likely to be wiped out
-> population can adapt to changing conditions and evolution can take place
