Exam 8: The Cellular Basis of Reproduction and Inheritance

Source: Adapted from C. A. Huether et al., Maternal age specific risk rate estimates for Down syndrome among live births in whites and other races from Ohio and Metropolitan Atlanta, 1970-1989, Journal of Medical Genetics 35: 482-90 (1998). Figure 8.20B Maternal age and incidence of Down syndrome -Which conclusion can best be drawn from this study?

If the four cells shown resulted from cell division of a single cell with diploid chromosome number 2n = 4, what best describes what just occurred?

Which of the following statements regarding mitosis and meiosis is true?

Mr. and Mrs. Smith have three sons in elementary school. Two of their children are progressing normally, but their youngest son, Charles, has been much slower than his siblings in developing speech and language skills. His parents are concerned that he has a learning disability and decide to investigate further. Since some learning disabilities can be genetically based, their pediatrician recommends a chromosomal analysis. The results show that Charles has a trisomy of the sex chromosomes, diagnosed as XYY. A mistake during sperm formation resulted in an extra copy of the Y chromosome. The extra copy was passed on to Charles during fertilization. Most often, this chromosomal change causes no unusual physical features or medical problems, but those with trisomy of the sex chromosomes may have a higher-than-normal risk of delays in learning development. -The problem that occurred during meiosis in sperm formation was

Two chromosomes in a nucleus that carry genes controlling the same inherited characteristics are

Which of the following shows the greatest promise as a cancer chemotherapy agent?

Which of the following is a feature of plant cell division that distinguishes it from animal cell division?

Which of the following statements regarding the differences between mitosis and meiosis is false?

The creation of genetically identical offspring by a single parent, without the participation of sperm and egg, is called

Prior to mitosis and after S phase, each chromosome of a eukaryotic cell consists of a pair of identical structures called

Plants grow taller through mitosis at the tips of their shoots (above ground) and at the tips of their roots (below ground). Here are two samples of tissue taken from a grass plant, one from the tip of the root and one from the mid part of the plant. Stage Sample 1 Sample 2 Interphase 74\% 98\% Prophase 18\% 0.5 Metaphase 4\% 0.2\% Anaphase 2\% 0.1\% Telophase 1\% 0.1\% -What can you conclude from these data?

You and your lab partner are observing a cell under a microscope, but you do not know whether it is a eukaryote or a prokaryote. Which of the following observations regarding the chromosomes would you use to immediately conclude that the cell is a eukaryote?

At the start of mitotic anaphase

Nondisjunction occurs when

Below are three statements. Classify them as examples of independent orientation, crossing over, or random fertilization. I: The formation of a zygote from an egg and a sperm is an unpredictable event. II: Random combinations of paternal and maternal chromosomes end up in gametes. III: An allele on the paternal chromosome 18 ends up on the maternal chromosome 18.

Strictly speaking, the phrase "like begets like" refers to

As a patch of scraped skin heals, the cells fill in the injured area but do not grow beyond that. This is an example of

How many generations does it take to develop a new plant species by polyploidy?

What event will immediately follow the event shown in the following image?

A karyotype is most like