Cell Division
Comparison
Number of parent cells
One
One
Number of divisions
One
# of daughter cells produced (in
animals)
Two identical daughter cells
Size of daughter cells relative to
parent cell
Smaller but will grow to the same
size as the parent cell
2 successive divisions:
Meiosis I- reduction division
Meiosis II- similar to mitosis
4 cells:
Human Male- 4 functional sperm
cells
Human Female- 1 functional egg cell
out of the 4 cells produced
In males, 4 functional sperm cells
are produced that are quite small
compared to the egg cell in females.
# of chromosomes in parent
Diploid number- 2n
46 in humans
Diploid number- 2n
46 in humans
# of chromosomes per daughter cell
at end of process
Diploid number- 2n
46 in humans
Haploid number- n
23 in humans
Genetic comparison: chromosomes
in parent cell versus daughter cell
Daughter cells receive the correct
number of chromosomes with an
exact copy of information from the
parent cell.
In all body (somatic) cells, with the
exception of reproductive organs
At the end of the 1st division of
meiosis, there are 2 daughter cells,
each with exactly half the number
of chromosomes of the parent cell.
Only in the reproductive organs in
designated cells (gametes,
reproductive cells, or sex cells)
Function of process
-Ensures genetic continuity within
the individual from cell to cell
-For growth, repair, & maintenance
Sexual or asexual reproduction?
Asexual
-Ensures genetic continuity from
one generation to the next for a
given species
-To prevent the doubling of
chromosome number from one
generation to the next
Sexual
Advantages
-Fast reproduction (identical clones)
-Requires only one parent
Variety of offspring well suited to
change (more genetic variability)
Disadvantages
-Difficult to adapt to a change in the
environment
-Slower process
-Requires 2 parent cells
Location of process in organism
(provide examples of specific cells)
Mitosis
Meiosis