AP Biology Big Idea 3 Labs Review (Genetics and Information Transfer)

The illustrations above represent homologous pairs of chromosomes as they might appear in various stages of mitosis and meiosis (2n = 2). At which stage do the chromosomes have the LEAST amount of DNA per cell?

• A

• B

• C

• D

• E

Refer to the graph, which illustrates the amount of DNA found in a cell during the cell cycle. Which phase of the cell cycle represents DNA replication?

• A

• B

• C

• D

Mitosis without cytokinesis will result in

• Two cells, each with two nuclei

• One cell with two nuclei

• One cell with one nucleus

• Two cells with two chromosomes

Which of the following occurs during mitosis but not during meiosis I?

• The chromosomes are pulled to opposite poles of the spindle apparatus.

• The chromatids of each chromosome are separated.

• Both synapsis and crossing-over take place.

• The diploid number of chromosomes is reduced to the haploid number.

A researcher examining a root tip observes a plant cell with condensed sister chromatids, kinetochores with attached microtubules, and individual chromosomes that are aligned at the equatorial plate of the cell. Which of the following best describes what the next process will be in the cell?

• Homologous chromosomes (each with two sister chromatids) will move toward opposite poles of the cell.

• Paired chromatids will separate, and the new daughter chromosomes will move toward opposite poles of the cell.

• The nuclear envelope will break down, and the spindle will begin to form.

• The chromatin will decondense, and the daughter cell will enter interphase.

The process depicted in the image above is best summarized by which of the following descriptions?

• During the synthesis phase of the cell cycle, DNA molecules replicate to generate identical daughter cells.

• Centromeres align specific gene sequences of homologous chromosomes during mitotic divisions

• The spindle apparatus attaches at chiasma during metaphase of mitosis.

• During meiosis, crossing over leads to recombination of alleles between homologous chromosomes.

In a transformation experiment, a sample of E. coli bacteria was mixed with a plasmid containing the gene for resistance to the antibiotic ampicillin (ampr). Plasmid was not added to a second sample. Samples were plated on nutrient agar plates, some of which were supplemented with the antibiotic ampicillin. The results of E. coli growth are summarized above. The shaded area represents extensive growth of bacteria; dots represent individual colonies of bacteria.

Plates that have only ampicillin-resistant bacteria

growing include which of the following?

• I only

• III only

• IV only

• I and II

In a transformation experiment, a sample of E. coli bacteria was mixed with a plasmid containing the gene for resistance to the antibiotic ampicillin (ampr). Plasmid was not added to a second sample. Samples were plated on nutrient agar plates, some of which were supplemented with the antibiotic ampicillin. The results of E. coli growth are summarized above. The shaded area represents extensive growth of bacteria; dots represent individual colonies of bacteria.

Which of the following best explains why there is no growth on plate II?

• The initial E. coli culture was not ampicillin resistant.

• The transformation procedure killed the bacteria.

• Nutrient agar inhibits E. coli grow

• The bacteria on the plate were transformed.

In a transformation experiment, a sample of E. coli bacteria was mixed with a plasmid containing the gene for resistance to the antibiotic ampicillin (ampr). Plasmid was not added to a second sample. Samples were plated on nutrient agar plates, some of which were supplemented with the antibiotic ampicillin. The results of E. coli growth are summarized above. The shaded area represents extensive growth of bacteria; dots represent individual colonies of bacteria.

Plates I and III were included in the experimental

design in order to

• demonstrate that the E. coli cultures were viable.

• demonstrate that the plasmid can lose its ampr gene.

• demonstrate that the plasmid is needed for E. coli growth.

• prepare the E. coli for transformation.

In a transformation experiment, a sample of E. coli bacteria was mixed with a plasmid containing the gene for resistance to the antibiotic ampicillin (ampr). Plasmid was not added to a second sample. Samples were plated on nutrient agar plates, some of which were supplemented with the antibiotic ampicillin. The results of E. coli growth are summarized above. The shaded area represents extensive growth of bacteria; dots represent individual colonies of bacteria.

Which of the following statements best explains why there are fewer colonies on plate IV than on plate III?

• Plate IV is the positive control.

• Not all E. coli cells are successfully transformed.

• The bacteria on plate III did not mutate.

• The plasmid inhibits E. coli growth.