Lecture 13 LaunchPad Assignment BIO 2170

For each description below, choose the type of cell division it characterizes. Each type of cell division may be used once, multiple times, or not at all. 1. Produces genetically identical daughter cells 2. Produces genetically unique daughter cells 3. Produces four daughter cells 4. Parent cell undergoes two rounds of cell division 5. Homologous chromosomes exchange DNA prior to dividing 6. Forms diploid daughter cells 7. Parent cell undergoes one round of cell division 8. Homologous chromosomes undergo synapsis 9. Follows a single round of DNA replication a. meiosis b. mitosis c. both mitosis and meiosis

1- B 2- A 3- A 4- A 5- A 6- B 7- B 8- A 9- C

Match each of the following terms with its definition. Definitions may be used once, more than once, or not at all. 1. Synapsis 2. Bivalent 3. Crossing over 4. Non-sister chromatids 5. Homologous chromosomes 6. Chiasmata 7. Centromere 8. Centrosome a. a four-stranded structure of homologous chromosomes in alignment b. the region of a chromosome where sister chromatids remain attached c. the physical breakage and reunion of non-sister chromatids during prophase I d. crosslike structures found in bivalents e. alignment of homologous chromosomes during prophase I f. paired chromosomes that share the same set of genes g. the microtubule organizing center h. chromatids in a bivalent that do not share a centromere

1- E 2- A 3- C 4- H 5- F 6- D 7- B 8- G

The number of daughter chromosomes in a human cell in anaphase II of meiosis is __________.

46

The second meiotic division resembles mitosis because: - All of these choices are correct. - chromosomes decondense during telophase II. - spindle microtubules attach from opposite directions to the centromere of each sister chromatid pair. - sister chromatids are separated during anaphase II to become the chromosomes of the daughter cells. - the daughter cells have the same number of chromosomes as the parent cell..

All of these choices are correct

.During meiosis I: - chromosomes undergo reductional division. - All of these choices are correct. - bivalents are formed during prophase I and are taken apart during anaphase I. - sister chromatids are not separated. - non-sister chromatids exchange maternal and paternal DNA.

All of these choices are correct.

Sexual reproduction results in an increase in genetic diversity because: - during metaphase I, the bivalents line up in a random orientation so that gametes inherit a random set of maternally and paternally derived chromosomes. - during prophase I, genes that are paternally and maternally derived recombine so that the gametes have chromosomes that are different from the parents' chromosomes. - All of these choices are correct. - during fertilization, the gametes that fuse are random so that a large number of chromosomal combinations

All of these choices are correct.

Which of the following is NOT true about gametes? - They are formed by meiotic cell division. - They have half as many chromosomes as a somatic cell of the same individual. - They are called eggs and sperm in animals. - They fuse to form a new organism during fertilization. - They are genetically identical to other gametes formed during meiosis.

They are genetically identical to other gametes formed during meiosis.

Which of the following statements is NOT true about sister chromatids? - They are the same as homologous chromosomes. - They are identical or nearly identical DNA sequences. - They are formed in the S phase of the cell cycle when the chromosome undergoes replication. - They are attached to each other at the centromere. - All of these statements about sister chromatids are true.

They are the same as homologous chromosomes.

Interphase involves all of the following steps except - preparation for DNA replication. - the synthesis of cellular components necessary for mitosis. - DNA replication. - All of these steps occur during interphase. - an increased condensation of chromatin.

an increased condensation of chromatin.

The centrosome is: - a region of the chromosome where kinetochores attach. - All of these choices are correct. - the microtubule organizing center for the mitotic spindle. - a region of the chromosome where microtubules attach to chromosomes during mitosis. - a region of the chromosome where sister chromatids are attached to each other.

the microtubule organizing center for the mitotic spindle