The Cell Cycle - MEIOSIS

Question 1

Somatic cells also called _________ cells
How many?
diploid =
made by _____________

Answer 1

aka - Body Cells
46 total
* diploid - 2 of each chromosome (2N)
* made by mitosis

Question 2

Gametes or ______ cells
How many?
haploid =
made by ___________

Answer 2

aka - Sex Cells
23 total
* haploid - 1 of each chromosome (1N)
* made by meiosis

Question 3

Homologous Chromosomes - a pair, one from each _____, each has the same ______ & _______ ______.
Carry all __________________ traits.

Answer 3

a pair of chromosomes, one from each parent

• each has the same length & same centriole position
• carries all inherited traits

Question 4

Meiosis - process of ___________ division in which the number of __________ is cut in ________

Answer 4

The process of reduction division in which the number of chromosomes is cut in half
Because . . . Sperm + Egg = YOU!

Question 5

What do the recombining sperm and egg form?

Answer 5

A zygote with 46 chromosomes

Question 6

Meiosis I is similar to ________________;
in PROPHASE I, each chromosome…………………..;
4 chromosomes =
crossing over allows the genetic material to ________

Answer 6

• very similar to mitosis
• in Prophase I, each chromosome seeks out its corresponding (homologous) chromosome to form a tetrad
  ~ 4 chromosomes (2 homologous pairs) in a tetrad
• Crossing over allows the genetic material to recombine

Question 7

Meiosis I - In METAPHASE I
the pairs of _________ chromosomes…..
centromeres………………

Answer 7

• the pairs of homologous chromosomes line up at the equator

* centromeres attach to spindle fibers

Question 8

Meiosis I - ANAPHASE I - TELOPHASE
___________ pairs……
sister chromatids……………

Answer 8

• homologous pairs separate

* sister chromatids STAY TOGETHER

Question 9

Meiosis II - Interphase and Prophase II
neither cell undergoes……….;
each cell contains…………….

Answer 9

• cells may undergo a brief interphase - neither cell undergoes a round of DNA replication
  ~ each cell contains one of the homologous pairs
• Prophase II is similar to before

Question 10

Meiosis II - Metaphse II, Anaphase II - Telophase II
the chromosomes do what?
Then the pairs of chromosomes do what?

Answer 10

Metaphase II - the chromosomes line up in the midddle

Anaphse II - Telophose - the pairs of chromosomes separate resulting in four different haploid cells

Question 11

Why are the the four daughter cells different?

Answer 11

• crossing over
• independent assortment
  ~ the lining of the chromosomes during metaphase is a random process - the 4 gametes have different combinations of chromosomes

Question 12

Mitosis vs. Meiosis - types of cells

Answer 12

Mitosis - body cells

Meiosis - gametes

Question 13

Mitosis vs. Meiosis - number of divisions

Answer 13

Mitosis - two divisions

Meiosis - one division

Question 14

Mitosis vs. Meiosis - replication during………….

Answer 14

Mitosis - replication during interphase

Meiosis - replication once during interphase (Meiosis I)

Question 15

Mitosis vs. Meiosis - daughter cells

Answer 15

Mitosis - 2 identical diploid daughter cells made

Meiosis - 4 different haploid daughter cells made

Question 16

Mitosis vs. Meiosis -purpose

Answer 16

Mitosis - growth and repair

Meiosis - genetic variation and reproduction

Question 17

Not all organisms share the same life cycle ~ asexual reproduction

Answer 17

the organism inherits all chromosomes from a single parent (ex. bacteria)

Question 18

Not all organisms share the same life cycle ~ asexual and/or sexual reproduction

Answer 18

some organisms reproduce by either asexual alone or a combination of sexual & asexual reproduction

Question 19

Karotyping is one way that geneticists check for _________; a way to analyze ____________ by _____________ them and ____________ them

Answer 19

• one way geneticists check for disorders is through karotyping
• a way to analyze chromosomes by staining and organizing them

Question 20

When things don’t go as planned . . . nondisjunction
When the chromosomes fail to _______ properly;
The gametes don’t have what?

Answer 20

When the chromosomes fail to separate properly
* the gametes don’t have the proper number of chromosomes

 ~ can be a partial break as well * during Metaphase I or Metaphase 2

Question 21

Nondisjunction -
Trisomy and
Monosomy

or a partial break during what phase?

Answer 21

~ trisomy - having 3 chromosomes of one kind
~ monosomy - having one particular type of chromosome
~ can be a partial break as well
* during Metaphase I or Metaphase 2