Biology Now, 2e

Toxic Plastic ■ 107

The first cytokinesis

takes place, producing

two haploid cells.

Each replicated

chromosome pairs

with its homologue.

Meiosis I

Prophase I Metaphase I Anaphase I Telophase I and Cytokinesis I

(^1) Homologous chromosome
pairs line up at the
metaphase plate, aided by
the spindle fibers.
(^2) The paternal and
maternal homologous
chromosomes separate
through the shortening
of the spindle fibers.

3 4

The meiotic spindle

pulls apart the sister

chromatids, and the

second cytokinesis

follows...

Meiosis II

Prophase II Metaphase II Anaphase II Telophase II and Cytokinesis II

There is no further DNA

replication before

meiosis II. Prophase of

meiosis II is just like

mitotic prophase (see

Figure 6.4).

(^5) Chromosomes line up
at the metaphase plate,
aided by the spindle
fibers.
(^67) ... resulting in four
haploid daughter cells.

8

Figure 6.8

Meiosis with cytokinesis creates haploid daughter cells

The homologous chromosomes of a diploid cell after interphase occurs are paired and then separated into

two haploid cells in meiosis I. Sister chromatids of these haploid cells are separated during meiosis II, each into

two haploid cells. Cytokinesis occurs at the end of both meiosis I and meiosis II. M

Q1: Is a daughter cell haploid or diploid after the first meiotic division? How about after the second

meiotic division?

Q2: What is the difference between homologous chromosomes and sister chromatids?

Q3: If the skin cells of house cats contain 38 homologous pairs of chromosomes, how many

chromosomes are present in the egg cells they produce?