Ch 6

Which statement is false?

• Only animal cells contain DNA; plant cells do not.

• DNA can serve as an “individual identifier.”

• With the exception of identical twins, every person’s DNA is unique.

• DNA carries instructions for the functions of every cell and enzyme in the body.

• DNA carries a record of evolutionary history.

Why has DNA analysis been effective recently at overturning faulty criminal convictions?

• Genetic evidence can determine if an individual is predisposed to criminal behavior.

• Scientific evidence was not admissible in U.S. courts until just recently.

• Juries have tended to exhibit biases against DNA evidence in the past; however, that trend is now changing.

• DNA evidence is a more reliable individual identifier compared to eyewitness testimony.

• Scientists only discovered in 2005 that each individual’s DNA is unique.

Which of these is not found in a strand of DNA?

• hydrogen bonds

• a 5-carbon sugar

• phosphate groups

• nitrogen-containing bases

• sterols

In every DNA molecule:

• the number of adenine molecules is the same.

• the total number of nitrogen-containing bases is the same.

• the sugar is deoxyribose.

• the order of nitrogen-containing bases is the same.

• a single sugar-phosphate backbone is present.

The complementary base pairs in a DNA molecule are stabilized by:

• ionic bonds.

• a salt bridge.

• hydrogen bonds.

• covalent bonds.

• the electrostatic interactions of the charged backbone.

In any DNA molecule, the number of guanine bases will:

• always be equal to the number of thymine bases.

• always be equal to the number of adenine bases.

• always be equal to the number of cytosine bases.

• sometimes be equal to the number of thymine bases and will sometimes be equal to the number of adenine bases.

• sometimes be equal to the number of cytosine bases and will sometimes be equal to the number of adenine bases.

In any DNA molecule, the number of thymine bases will:

• always be equal to the number of cytosine bases.

• always be equal to the number of adenine bases.

• always be equal to the number of uracil bases.

• sometimes be equal to the number of cytosine bases and sometimes equal to the number of adenine bases.

• sometimes be equal to the number of guanine bases and sometimes equal to the number of cytosine bases.

If one strand of a DNA molecule has the base sequence ATTGCAT, its complementary DNA strand would be:

• ATTGCAT.

• TAACGTA.

• GCCATGC.

• CGGTACG.

• UAACGUA.

The human genome is composed of approximately how many base pairs?

• 3 billion

• 10 billion

• 30 billion

• 100 billion

• 1 trillion

The color of a daisy’s petals is a(n) ________, the instructions for which are found in a gene controlling petal color. There may be many alternate versions of this gene, which are called __________.

• trait; chromosomes

• trait; alleles

• base pair; alleles

• base pair; traits

• allele; traits