Bio Lab QUIZ 4:DNA & Genetics

Alternate forms of the same gene are called _____. -genotypes -crosses -cofactors -alleles

Why does DNA flow toward the positive side of the gel chamber? -none of the answer choices are correct -Gravity draws the DNA to the positive side. -DNA has a neutral charge and is attracted by the positive side. -DNA has a negative charge and is attracted by the positive side. -DNA has a positive charge and is attracted by the positive side.

In a heterozygous individual the allele being expressed is _____. -recessive -redundant -dominant -masked -epistatic

An allele for a particular trait that is only expressed when present in two copies is called a(n) _____. -codominant gene -incompletely dominant gene -multiple allele -recessive allele -dominant allele

If the two alleles for a particular gene are identical the gene pair is: -homologous. -heterozygous. -dominant. -recessive. -homozygous.

Traits that are carried on the X chromosome are said to be ________________. -x-linked -alleles -autosomal -gametal

Why is bromophenol blue added to the individual DNA samples? -none of the answer choices are correct -It allows the observer to view how far the DNA samples travel. -It is negatively charged, and will pull the DNA samples towards the positive side of the chamber. -It helps separate the DNA bands in each sample. -It stabilizes the DNA samples.

In gel electrophoresis, what is the agarose used for? -marking the DNA samples -mixing the DNA samples -making the dye -making the gel -none of the answer choices are correct

A DNA fragment with 100 base pairs is smaller than a DNA fragment with 150 base pairs. -True -False

The ________ of an organism is the physical appearance resulting from the expression of the genes present. -plasticity -karyotype -phenotype -genotype

Let P = purple flowers and p = white, and T = tall plants and t = dwarf. What combinations of gametes could be produced by a heterozygote for both the traits? -Pp, Tt -PpTt only -infertile, no gametes produced -PT, Pt, pT, pt -P, p, T, t

All gametes contain: -one set of chromosomes. -one chromosome. -two different sets of chromosomes. -two chromosomes. -two identical sets of chromosomes.

It is not necessary to change pipet tips when you micropipet each new DNA sample. -True -False

DNA can be collected on a glass rod in a technique called: -shaking. -curling. -spinning. -swirling. -spooling.

When Mendel crossed two purple-flowered pea plants with each other, he obtained a phenotypic ratio of 3:1 (purple-flowered pea plants to white-flowered pea plants). His results are consistent with which of the following sets of parents? -heterozygous purple pea plant and heterozygous purple pea plant -heterozygous purple pea plant and homozygous dominant purple pea plant -heterozygous purple pea plant and homozygous recessive white pea plant -homozygous dominant purple pea plant and homozygous recessive white pea plant -homozygous dominant purple pea plant and heterozygous white pea plant

What is DNA isolation? -The rupturing of the DNA molecule. -Copying of the DNA molecule. -The extraction of DNA from viruses or cells. -Measuring the DNA molecule for transport. -The moving of DNA from 1 cell to another.

Ethidium bromide is a dye that is used to stain the gel and allows the DNA to be viewed under UV light. -True -False

Detergent is used in the DNA isolation process because: -none of the answer choices are correct -it allows the precipitate to form. -it facilitates homogenization. -it stabilizes the DNA. -it binds the negative ends of DNA.

In the DNA isolation process, detergent was used to: -homogenize the cellular and nuclear membranes. -neutralize the cellular and nuclear membranes. -liquify the cellular and nuclear membranes. -emulsify cellular and nuclear membranes. -stabilize the cellular and nuclear membranes.

Let P = purple flowers and p = white, and T = tall plants and t = dwarf. What would be the appearance of a plant with the genotype PpTt? -purple flowers, dwarf -purple flowers, tall -white flowers, dwarf -pale purple flowers, intermediate height -white flowers, tall

Recessive alleles seem to vanish in some generations and reappear in later generations because: -they cannot be expressed in successive generations. -they cannot be expressed in females. -they are masked by a dominant allele. -they are lost by mutation. -they cannot be expressed in males.

Where would the DNA be located within a eukaryotic cell? -none of the answer choices are correct -cell membrane -cytoplasm -nucleus -golgi apparatus

In order to prevent the DNA from breaking, the glass rod should be spun: -in one direction. -clockwise and then counterclockwise. -none of the choices are correct -very slowly. -very quickly.

Let P = purple flowers and p = white, and T = tall plants and t = dwarf. Of the 16 possible gamete combinations in the dihybrid cross PpTt x PpTt, how many would be the phenotype white, tall? -none -16 -1 -9 -3

Ethanol is used in the DNA isolation process because: -it binds the negative ends of DNA. -none of the answer choices are correct -it facilitates homogenization. -it allows the precipitate to form. -it stabilizes the DNA.

A diploid organism that has two identical alleles for the same trait is called _______ for that particular trait. -dominant -homozygous -recessive -heterozygous -codominant

A portion of DNA that encodes a specific protein is called a(n) ________. -gene -centromere -kinetochore -chromosome -chromatid

How does the DNA rate of travel differ for small DNA fragments and large DNA fragments? -The rate of travel depends on the pH, not on the size of the fragments. -The rate of travel depends on the DNA charge, not on the size of the fragments. -Large fragments travel farther than small fragments. -Small fragments and large fragments travel at the same rate. -Small fragments travel farther than large fragments.

If a female was a carrier for sex-linked color blindness, what percentage of her male children would also be color blind? -25% -0% -50% -100%

In the DNA isolation process, ___________________________ is used to break down the protein complexes, and allow the DNA molecules to easily precipitate. -none of the answer choices are correct -meat tenderizer -ethanol -salt -sodium chloride