Unit 7 Review Questions

• Describe the claim that Watson and Crick examined and how they proved this claim.

• Describe the claim that Hersey and Chase researched and what evidence they corrected to prove this claim.

• If a DNA molecule has 40% cytosine, how much adenine does this molecule have? Who performed the first such test? What claim did they test with this?

• Describe what evidence Meselson and Stahl collected to support the claim that DNA replication is semiconservative.

• Provide a reasoning to connect the evidence from the previous question with the claim.

• Determine the chromosome numbers if the diploid number of the organism is 50:– Number of chromosomes in haploid cells:– Number of chromatids in a haploid cell during

metaphase:– Number of chromatids during metaphase I,

meiosis:– Number of chromosomes at the end of metaphase

II • List three processes that can result in genetic

variety• Describe the structure of DNA

• Describe the structure of chromosomes:• Compare and contrast mitosis in plants and

animals• Give 5 differences between mitosis and meiosis• Why does the cell cycle need to be regulated?• Describe the process of regulating the cell cycle

by cyclins and cdk’s • Differentiate between DNA replication on the

leading and lagging strand.• Describe how the Hershey and Chase

experiment contributed to the discovery of DNA.

• Haplopappus is an annual flowering plant that grows in deserts. It has a 2n number of only four. – This means that the cells in the vegetative parts of

the plant that are not undergoing mitosis have how many DNA molecules?

– During metaphase of mitosis, how many DNA molecules would be in the nucleus?

• What phase of the cell cycle are most body cells in?

• List and describe the external environmental factors that influence the cell cycle.

• A horticulturalist breeds orchids, trying to obtain a plant with a unique combination of desirable traits. After many years she finally succeeds. To produce more plants like this one, should she cross-breed it with another plant or clone it? Why?

• Each sperm cell of a pea plant contains seven chromosomes. What are the haploid and diploid numbers of this plant?

• Identify the stage and type of cell division you see on the picture.

• Determine the haploid and diploid number of this cell.

• Label the chromosomes (duplicated or not duplicated ?), centromere, nonsister chromatids, homologous chromosomes, chiasmata, sister chromatids, spindle fibers, centrioles