Chapter 13 mastering biology assignment

takes place only in the gonads

meiosis

only time that chromosomes line up by homologous pairs

meiosis I

the two homologs of a pair move toward opposite poles of dividing cell during

meiosis I

If you look through a microscope and see a cell with chromosomes lined up two by two, what stage of cellular reproduction must you be looking at?

meiosis I only

Homologous pairs of chromosomes are lined up independently of other such pairs during ____

metaphase I

goes on continuously in most parts of the body

mitosis

of the two processes we learned about which is going on in my hand right now

mitosis

Crossing over, resulting in an increase in genetic variation, occurs between ____

nonsister chromatids of homologous chromosomes

If the DNA content of a diploid cell is x in the G1 phase of the cell cycle and 2x at metaphase of meiosis I, then the DNA content of the same cell at metaphase of meiosis II will be

not 2x or 0.5 correct answer withheld

meiosis II is similar to mitosis in that

sister chromatids separate during anaphase

Imagine that I've taken a snapshot of chromosomes in a hypothetical cell. What stage of the life cycle must the cell be in?

the start of meiosis I

Imagine you found a hypothetical organism, you examine one of its gametes, and you see that it contains 5 chromosomes. How many chromosomes will one of its body cells contain just before mitosis begins?

10

In human gamete production there is an average of ____ crossover events per chromosome pair.

2-3

If the DNA content of a diploid cell in the G1 phase of the cell cycle is x, then the DNA content of the same cell at metaphase of meiosis I will be

2x

which of these gametes contains one or more recombinant chromosomes

B and C

Which of these gametes contain one or more recombinant chromosomes?

B, C, F, and G

the parent cell that enters meiosis is diploid, whereas the four daughter cells that result are haploid. which statement correctly describes how cellular dna content and ploidy levels change during meiosis I and meisosis II

DNA content is halved in both meiosis I and meiosis II. Ploidy level changes from diploid to haploid in meiosis I, and remains haploid in meiosis II

a human cell containing 22 autosomes and a Y chromosome is

a sperm

You may remember this shot from the video podcast, here I am representing a duplicated chromosome. What structure is represented by my waist, where I am joined to my twin?

centromere

point of attachment between two sister chromatids of a duplicated chromosome

centromere

which processes lead to most genetic variation in sexually reproducing organisms

crossing over, random fertilization, independent assortment of chromosomes in meiosis