Mastering Biology CH 8 Core Content

Homologous chromosomes migrate to opposite poles during _____. (Meiosis) metaphase II anaphase I metaphase I telophase II and cytokinesis prophase II

anaphase I During anaphase I sister chromatids remain attached at their centromeres, and homologous chromosomes move to opposite poles.

During _____ sister chromatids separate. (Meiosis) interphase prophase II anaphase II metaphase I prophase I

anaphase II Anaphase II is essentially the same as mitotic anaphase except that the cell is haploid.

Meiosis II typically produces _____ cells, each of which is _____. (Meiosis) two... diploid four ... identical to the other four ... haploid two ... haploid four ... diploid

four ... haploid At the end of meiosis II there are typically 4 haploid cells.

If you look through a microscope and see aterm-21 cell with chromosomes lined up two by two, what stage of cellular reproduction must you be looking at? (Mitosis vs. Meiosis) mitosis only meiosis II only either mitosis or meiosis I either meiosis I or meiosis II

meiosis I only Meiosis I is the only time that chromosomes line up by homologous pairs.

During _____ chromosomes align single file along the equator of a haploid cell. (Meiosis) telophase I and cytokinesis prophase I anaphase I metaphase II metaphase I

metaphase II Metaphase II is essentially the same as mitotic metaphase except that the cell is haploid.

Of the two processes we learned about, which is going on in my hand right now? (Mitosis vs. Meiosis) mitosis meiosis gametogenesis both mitosis and meiosis none of the above

mitosis Mitosis goes on continuously in most parts of the body, whereas meiosis takes place only in the gonads.

Synapsis occurs during _____. (Meiosis) prophase I anaphase II metaphase II telophase I and cytogenesis prophase II

prophase I Synapsis, the pairing of homologous chromosomes, occurs during prophase I.

During _____ a spindle forms in a haploid cell. (Meiosis) prophase I metaphase II anaphase II telophase I and cytokinesis prophase II

prophase II Prophase II is essentially the same as mitotic prophase except that the cells are haploid.

Imagine I've taken a snapshot of the chromosomes in a hypothetical cell. Two chromosomes lined up. You and your twin and your friends and her twin. Part of that snapshot looks like this. What stage of the life cycle must that cell be in? (Mitosis vs. Meiosis) the start of meiosis I just after meiosis I the start of mitosis just before mitosis the start of meiosis II

the start of meiosis I We can see that the chromosomes are duplicated and lined up by homologous pair. That only happens at the start of meiosis I.

Meiosis I produces _____ cells, each of which is _____. (Meiosis) two ... haploid two... diploid two... identical to the other four ... diploid four ... haploid

two ... haploid At the end of meiosis I there are 2 haploid cells.

What name is given to this process? To view the animation, click here. Then click on the image to start the animation. (Asexual and Sexual Life Cycles) gametogenesis sexual reproduction meiosis asexual reproduction fertilization

Asexual reproduction A single individual is reproducing.

Gametes are produced by _____. (Asexual and Sexual Life Cycles) meiosis fertilization mitosis the cell cycle asexual reproduction

Meiosis Meiosis produces haploid gametes from a diploid parental cell.

What is different concerning the DNA in bacterial cells as opposed to eukaryotic cells? (Cell Division for Bacteria) A) the amount of DNA present B) whether the DNA is housed in a nucleus or not C) whether the DNA is linear or circular D) all of the above are differences between prokaryotic and eukaryotic DNA

all of the above are differences between prokaryotic and eukaryotic DNA All of the above are appropriate answers.

Which processes lead to most genetic variation in sexually reproducing organisms? (Origins of Genetic Variation) A) independent orientation of chromosomes in meiosis B) crossing over C) random fertilization D) cytokinesis

A) independent orientation of chromosomes in meiosis, B) crossing over, & C) random fertilization

At the end of _____ and cytokinesis, haploid cells contain chromosomes that each consist of two sister chromatids. (Meiosis) telophase interphase telophase II metaphase II telophase I

telophase I At the end of telophase I and cytokinesis, there are 2 haploid cells with chromosomes that consist of two sister chromatids each.

At the end of _____ and cytokinesis there are four haploid cells. (Meiosis) prophase I interphase telophase II anaphase I prophase II

telophase II At the end of telophase II and cytokinesis there are four haploid cells.

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? (Mitosis vs. Meiosis) 5 10 15 20 the answer cannot be determined

10 If the hypothetical organism has 5 chromosomes in one of its gametes, then it must have 10 chromosomes in a body cell. Just before mitosis, the chromosomes in a body cell are duplicated, but the sister chromatids remain joined together. So you will see 10 (duplicated) chromosomes in a typical body cell.

A diploid organism whose somatic (nonsex) cells each contain 32 chromosomes produces gametes containing _____ chromosomes. (Asexual and Sexual Life Cycles) 16 8 64 30 32

16 16 is half of 32.

Normal human gametes carry _____ chromosomes. (Asexual and Sexual Life Cycles) 23 pairs of 5 23 46 pairs of 46

23 This is the number of chromosomes in a single set of human chromosomes.

Asexual reproduction __________. A) can produce offspring genetically identical to the one single parent B) leads to a loss of genetic material in the offspring C) is limited to plants D) produces offspring that always look exactly like the parent

can produce offspring genetically identical to the one single parent Only one individual makes a genetic contribution to the offspring. Often, but not always, this results in offspring that are genetically identical to the one single parent.

Which of these gametes contains one or more recombinant chromosomes? (Origins of Genetic Variation) A and C A and D B and C D and E A and B

B and C Each of the chromosomes in gametes B and C are composed of material derived from both parents.

Which of these cells is (are) haploid? (Asexual and Sexual Life Cycles) C and D A and D B and C D B

C and D Once meiosis I is completed, cells are haploid.

The first step of bacterial replication is _____. (Cell Division for Bacteria) A) DNA replication B) attachment of the DNA to the plasma membrane C) pinching of the plasma membrane D) separation of daughter cells

DNA replication The DNA must be copied in order to proceed.

Replication of chromosomal DNA occurs __________. A) in the cytoplasm of a eukaryotic cell B) to repair gene damage caused by mutation C) before a cell divides D) whenever a cell makes protein

before a cell divides Chromosomes replicate before cell division. This ensures that genetic material is appropriately distributed to the daughter cells.

Bacteria divide by: (Cell Division for Bacteria) mitosis sexual reproduction binary fission meiosis

binary fission Binary fission is the method used by bacteria to divide.

Here i am representing a duplicated chromosome. What structure is represented by my waist where I am joined to my twin? (Mitosis vs. Meiosis) centrosome telomere chromosome centromere tetrad

centromere The centromere is the point of attachment between two duplicated chromosomes.

Most of an organism's DNA is carried by its __________. mitochondria chromosomes nucleoli endoplasmic reticulum

chromosomes An organism's chromosomes carry most of its DNA, but some is found on small DNA molecules in mitochondria and chloroplasts.