Get out the Meiosis and
Sexual Reproduction
Outreach Notes we
did as homework
last class period.
Use the information to
create a poster that
would teach someone
about the processes we
have just researched.
If you examined the nucleus of a cell
of a pea plants, you would find that
it had 14 chromosomes (7 pairs)
One chromosome in each
pair came from the male
parent and the other
from the female.
A cell with two of each kind of
chromosome is called a diploid
or 2N
The two chromosomes
of each pair in a
diploid cell (2N) are
called
Organisms produce gametes (you
remember sperm or eggs) that contain
one of each kind of chromosome.
A cell containing one of each type of
chromosome is called a haploid cell
or N
Chromosome Number of Common Organisms
Organism
Body Cell (2N)
Gamete (N)
Fruit Fly
8
4
Garden Pea
14
7
Corn
20
10
Leopard Frog
26
13
Human
46
23
Chimpanzee
48
24
Adders Fern
1260
630
When cells divide by mitosis
the new cells have exactly
the same number and kind of
chromosomes.
For example, if mitosis was the only means
of cell division, in fruit flies the first
generation would have 8 chromosomes.
2nd Generation
16
3rd Generation
4th Generation
32
64
Results in new
combinations of
alleles on a
chromosome.
Which of these represents the number
of chromosomes in cells before and
after the process of meiosis?
A.)
B.)
nn
n  2n
2n  n
D.) 2n  2n
C.)
Which of the following cells are the
result of meiosis?
A.) sperm cells
B.) liver cells
C.) bacteria
D.) all the above
E.) only B & C
Which of the following steps would not
lead to genetic variation?
A.) Crossing over of homologous
chromosomes
B.) Random alignment of the
chromosomes during metaphase
C.) The combination of genes from the
sperm and egg
D.) Alignment of chromosomes during
prophase II
Crossing-over occurs during:
A.) anaphase 1
B.) metaphase 1
C.) prophase 1
D.) prophase 2
Which of the chromosomes below
are homologous?
A.
B.
C.
D.
E.
A cell with a diploid number of 24
undergoes meiosis, how many
chromosomes are in each daughter
cell?
A.) 6
B.) 12
C.) 24
D.) 48
The overall function of meiosis includes
all of the following except _____?
A.) gamete reproduction
B.) growth of the cell
C.) reduction of chromosome number
from 2N to N
D.) providing genetic variation to
sexually reproducing organisms.
Which of these represents the number
of chromosomes in cells before and
after the process of meiosis?
A.)
B.)
nn
n  2n
2n  n
D.) 2n  2n
C.)
Which of the following cells are the
result of meiosis?
A.) sperm cells
B.) liver cells
C.) bacteria
D.) all the above
E.) only B & C
Which of the following steps would not
lead to genetic variation?
A.) Crossing over of homologous
chromosomes
B.) Random alignment of the
chromosomes during metaphase
C.) The combination of genes from the
sperm and egg
D.) Alignment of chromosomes during
prophase II
Crossing-over occurs during:
A.) anaphase 1
B.) metaphase 1
C.) prophase 1
D.) prophase 2
Which of the chromosomes below
are homologous?
A.
B.
C.
D.
E.
A cell with a diploid number of 24
undergoes meiosis, how many
chromosomes are in each daughter
cell?
A.) 6
B.) 12
C.) 24
D.) 48
The overall function of meiosis includes
all of the following except _____?
A.) gamete reproduction
B.) growth of the cell
C.) reduction of chromosome number
from 2N to N
D.) providing genetic variation to
sexually reproducing organisms.