MITOSIS/MEIOSIS REVIEW
1 What is the rhythmic change in cyclin concentration in a cell cycle due to Its destruction by an enzyme phosphorylated by MPF.
3 Which of the following organisms does not reproduce cells by mitosis? bacterium B Cytokinesis often, but not always, follows mitosis. If cells undergo mitosis and not cytokinesis, this would result in cell structures with two or more nuclei.
5 Regarding mitosis and cytokinesis, one difference between higher plants and animals is that in plants . a cell plate begins to form at telophase, whereas in animals a cleavage furrow is initiated at that stage.
Answer the question(s) below that consist of five numbered headings concerned with the cell cycle. For each phrase or sentence, select the heading that is most closely related to it. Each heading may be used once, more than once, or not at all. 1. G0 2. G1 3. S 4. G2 5. M
7 The "restriction point" occurs here. 2
9 The shortest part of the cycle. 5
11 Cyclin is destroyed toward the end of this phase. 5
Refer to the terms below to answer the following question(s). Each term may be used once, more than once, or not at all. 1. telophase 2. anaphase 3. interphase 4. metaphase 5. prophase
13 DNA replication takes place. 3
15 This is the longest of the mitotic stages 5
17 The centromere is a region in which chromatids are attached to one another.
19 All of the following are characteristic of telophase of mitosis/ Cytokinesis begins. /The nuclear envelope reappears. /. Chromosomes begin to condense together. / Astral microtubules disappear.
21 During which phase of mitosis are two-chromatid chromosomes found? from G2 of interphase through metaphase
23 All of the following occur during the latter stages of mitotic prophase/ centrioles move apart. / nucleolus disintegrates./ nuclear envelope disappears. / spindle is organized.
25 If the haploid number for a species is 3, each dividing diploid cell will have how many chromatids at metaphase? 12
27 How many chromosomes will a cell have during mitotic anaphase if the diploid chromosome number is 4? 8
29 The phases of meiosis that cause the most variation in the four resulting daughter cells are prophase I and anaphase I
31 How does the sexual life cycle increase the genetic variation in a species?
1. by producing gametes with different combinations of parental chromosomes
2. by allowing the combination of chromosomes from two different individuals
3. by allowing recombination of alleles on a chromosome
33 Which of the following is true of a species that has a chromosome number of 2n = 16? A gamete from this species has 8 chromosomes.
35 Any genetic differences in a clone are due to which process? mutation
37 How do cells at the completion of meiosis compare with the cell from which they were derived?
They have half the number of chromosomes and half the amount of DNA.
39What is a human cell that contains 22 pairs of autosomes and two X chromosomes? a female somatic cell
41 Crossing over occurs during which phase of meiosis? prophase I Use the key shown below to answer the following question(s). Each answer may be used once, more than once, or not at all.
1. If the statement is true for mitosis only
2. If the statement is true for meiosis I only
3. If the statement is true for meiosis II only
4. If the statement is true for mitosis and meiosis I
5. If the statement is true for mitosis and meiosis II
43 This occurs when a cell divides to form two cells that are genetically identical.1E Centromeres uncouple and chromatids are separated from each other.5
Match the key event of meiosis with the stages listed below, to answer the following question(s).
I. Prophase I VI. Prophase II
II. Metaphase I VII. Metaphase II
III. Anaphase I VIII. Anaphase II
IV. Telophase I IX. Telophase II
V. Interkinesis
45 Tetrads of chromosomes align at the metaphase plate; independent assortment soon follows. II
47 Nuclear envelopes may form; no replication of chromosomes takes place.V
49 All of the following are functions of meiosis in plants / production of spores. /reduction of chromosome number in half. /independent assortment of chromosomes. / crossing over and recombination of homologs.
51 After telophase I of meiosis, what is the chromosomal make-up of each daughter cell?
haploid, and the chromosomes are composed of two chromatids
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