Bio final Test 4

A human cell containing 22 autosomes and a Y chromosome is

A sperm

The two homologs of a pair move toward opposite poles of a dividing cell during

meiosis 1

Meiosis 2 is similar to mitosis in that

sister chromatids separate during anaphase

If the DNA content of a diploid cell in the G1 phase of the cell cycle is x, then the DNA content of the same cell at metaphase of meiosis 1 will be

2x

DNA content of a single cell at metaphase of meiosis 2 will be

x

What is the difference between monohybrid crosses and dihybrid crosses

Dihybrid have organisms that are heterozygous for 2 characters and a monohybrid has organisms that are heterozygous for only one charcter

What was the most significant conclusion that Gregor Mendel drew from his experiments

Traits are inherited in genes not blended

How many unique gametes could be produced through independent assortment by an individual with the genotype AaBbCCDdEE

8

What is the law of independent assortment

Behavior of two or more genes relative to one another

Mendel’s law of independent assortment has its basis in what event of meiosis

alignment of pairs of chromosomes in the middle of a cell

A man and woman both show normal pigmentation, but both have one parent who has albinism. What is the probability that their first child will have albinism

¼

What phenotype is an example of polygenic inheritance

Skin pigmentation in humans

A woman who has blood type A positive has a daughter who is type O positive and a son who is type B negative. What phenotype is possible for the father

B positive

An obstetrician knows that one of her patients is a pregnant woman whose fetus is at risk for a serious disorder that is detectable biochemically in fetal cells. The obstetrician would most reasonably offer what treatment to her patient?

Amniocentesis or CVS

What is an example of monosomy in humans

Turner syndrome

Cinnabar eye color is a sex-linked, recesssive characteristic in fruit flies. If a female having cinnabar eyes is crossed with a wild-type male, what percentage of the F1 males will have cinnabar eyes.?

100%

A man who is a dwarf with achondroplasia and normal vision marries a color-blind woman of normal height. The man’s father was 6 feet tall, and both the woman’s parents were of average height. Dwarfism caused by achondroplasia is autosomal dominant, and red-green color blindness is x-linked recessive. What proportion of their sons would be color blind and of normal height?

Half

If a man with an X linked allele has children, which of his children will inherit it

His daughters

What is one map unit

A 1% frequency of recombination between 2 genes

One possible result of chromosomal breakage is for a fragment to join a nonhomologous chromosome. What is this type of chromosomal alteration called?

Translocation

In his work with pneumonia causing bacteria and mice, Griffith found that

Some sustance from pathogenic cells was transferred to nonpathogenic cells, making them pathogenic

What is the basis for the difference in how the leading and lagging strands of DNA molecules are synthezised

DNA polymerase can join new nucleotides ontly to the 3’ end of a pre existing strand and strands are antiparallel

In analyzing the number of different bases in a DNA sample, which result would be consistent with the base-pairing rules

A+G=C+T

The enlongation of the leading strand during DNA synthesis

Depends on the action of DNA polymerase

In a nucleosome, DNA is wrapped around

Histones

What describes the process of transformation in bacteria

External DNA is taken into a cell becoming apart of its genome

In E.Coli, which enzyme catalyzes the enlongation of new DNA strand in the 5’-3’ direction

DNA ligase

What correctly describes the difference between ATP and the nucleotides used during DNA synthesis

The nucleotides have the sugar deoxyribose; ATP has the sugar ribose

What correctly decribes the difference between the leading and lagging strands of Dna during DNA replication

Leading strand is synthesized in the direction of the replication fork and lagging strand is synthesized in the opposite direction

E. Coli cells grown on 15N medium are transferred to 14N medium and allowed to grow for two more generations. DNA extracted from these cells is centrifuged. What density distribution of DNA would you expect?

One low density and one intermediate density band

A biochemist isolates, purifies, and combines in a test tube a variety of molecules needed for DNA replication. When she adds some DNA to the mixture, replication occurs, but each DNA molecule consists of a normal strand paired with numerous segments of DNA a few hundred nucleotides long. What has she probably left out of the mixture

Primase

The spontaneous loss of amino groups from adenine in DNA results in hypozanthine, an uncommon base, opposite thymine. What combination of proteins could repair such damage

Nuclease, DNA polymerase, DNA ligase