Meiosis

In humans, the haploid number of chromosomes is ____.

• 23

• 46

• 69

• 92

Which of the following is the best definition for MEIOSIS?

• the process of two haploid cells uniting

• the counting of chromosomes within a diploid cell

• a two-step process that reduces the number of chromosomes in half such that there is only one copy of all the chromosomes

• the equational division of a cell into two identical copies

True or False? Before cells undergo meiosis they pass through interphase first.

• true

• false

What is unique to Prophase I- is that the duplicated chromosomes pair up to form _______.

• a centrosome

• a tetrad

• the mitotic spindle

• sister chromatids

In which stage of MEIOSIS does crossing over occur? (The exchange of genetic material between chromosomes in a tetrad.)

• Anaphase I

• Metaphase I

• Prophase I

• Telophase I

In Metaphase I, tetrads line up along the _______.

• mitotic spindle

• centrosomes

• equatorial plane

• contractile ring

In Anaphase I, the _________ are separated by the pulling of the spindle fibers to opposite poles of the cell.

• homologous pairs of chromosomes

• sister chromatids

• centromeres

• centrosomes

Check all of the following that DO occur during Telophase I and cytokinesis.

• The separated homologous chromosomes are at opposite poles of the cell.

• The cell divides in two.

• The chromosomes do not uncoil, since they are getting ready for Meiosis II.

• Sister chromatids are pulled away from each other.

At the start of Meiosis II, which of the following is NOT true?

• There are two cells.

• The cells are haploid.

• The chromosomes are paired up as homologues.

• DNA is present as two sister chromatids joined at the centromere.

In Prophase II, the_________ reforms and the spindle fibers attach to each chromosome.

• mitotic spindle

• centrosomes

• nucleus

• cell plate