Which of the following people conducted the experiments that demonstrated that DNA is the genetic material of bacteriophages?
Hershey and Chase
One type of virus that infects bacteria is called a
When a T2 bacteriophage infects a Escherichia coli cell which part of the phage enters the bacteria cytoplasm?
only the DNA
the monomers of DNA and RNA are
Which of the following statements regarding DNA is false?
DNA uses the nitrogenous base uracil
which of the statements regarding RNA is false?
RNA uses the sugar dextrose
how would the shape of a DNA molecue change if adenine paired with guanine and cytosine paired with thymine?
the DNA molecule would have irregular widths along its lenth
the shape of a DNA molecule is most like?
a twisted rope laddder
which of the following statements regarding a DNA double helix is always true?
the amount of adenine is equal to the amount of thymine and the amount of guanine is equal to te amount of cytosine
uses each strand of a DNA molecule as a template for the creation of a new strand
If one strand of DNA is CGGTAC, the corresponding strand would be
multiple origins of replication on the DNA molecules of eukaryotic cells serve to
shorten the time necessary for DNA replication
which of the following enzymes catalyzes the elongation of a new DNA strand?
Which of the following options best depicts the flow of information when a gene directs the synthesis of a celular component
DNA to rRNA to mRNA to protein
the transfer of genetic information from DNA to RNA is called
the "one gene-one polypeptide " theory states that
the function of an individual gene is to dictate the production of a specific polypeptide
experiments have demonstrated that the "words" of the genetic code (the units that specify amino acids) are
a base substitution mutation in a gene does not always result in a different protein. Which of the following factors could account for this?
the fact that some amino acids are specified from more than one codon
which of the following enzymes catalyzes the linking together or RNA nucleotides to form RNA?
____ marks the end of a gene and causes transcription to stop
where do transcription and translation occur in prokaryotic cells
in the cytoplasm
which of the following takes place during translation
the conversion of genetic information form the language of nucleic acids to the language of proteins
which of the following statements is false
an mRNA molecule transcribed from DNA is shorter than the genetic message it carries
Which of the following options most accurately lists the sequence of events in translation
codon recognition to peptide bond formation to translocation to termination
any change in the nucleotide sequence of DNA is called
consider the following sequences: "The dog did not eat" Which of the following variations of this sequence is most like a base substitution mutation?
the doe did not eat
a physical or chemical agent that changes the nucleotide sequence of DNA is called a
a protein shell enclosing a viral genome is known as a
viral DNA incorporated into host cell DNA is known as a
which of the following statements about herpes virus is false
herpes viruses reproduce inside the host cell's mitochondria
which of the following statements regarding viral diseases is false
very frew new human diseases have originated in other animals because the genetic differences are too great
what kind of virus is HIV
which of the following enzymes does HIV use to synthesize DNA on an RNA template
HIV does the greatest damage to
white blood cells
conjugation, transformation, and transduction are all ways that bacteria
increase their genetic diversity
in many bacteria genes that confer resistance to antibiotics are carried on
which of the following human activities has contributed to an increase in the number of bacteria having R plasmids
heavy use of antibiotics in medicine and in agriculture
the most likely method by which the mutated CCR5 gene prevents AIDS
coding for a protective protein in the cell membrane
which of the following shows the steps of viral infection in the proper order
virus locates host cells to penetrates cell membrane to enter nucleus to alters host cell DNA to host cell produces copies of viruses
mendel conducted his most memorable experiments on
which of the following statements regarding cross-breeding and hybridization
the hybrid offspring of a cross are the P one generation
a monohybrid cross is
a breeding experiment in which the parental varieties differ in only one character
which of the following statements regarding genotypes and phenotypes is false?
an allele that is fully expressed is refereed to as a recessive
all the offspring of a cross between a black eyed Mendelian and an orange eyed Mendelian have black eyes. this means that the allele for black eyes is ____ the allele for orange eyes.
all the offspring of a cross between a black eyed Mendelian and an orange eyed Mendelian have black eyes. what is the expected phenotype ratio of a cross between two orange eyed mendeliens?
0 black eyed; 1 orange eyed
the alleles of a gene are found at ___ chromosomes.
the same locus on homologous
the phenotypic ratio resulting from a dihybrid cross showing independent assortment is expected to be
nine to three to three to one
imagine that we mate two black Labrador dogs with normal vision and find that three of the puppies are like the parents, but one puppy is chocolate with normal vision and another is black with PRA (progressive retinal atrophy, a serious disease of vision). We can conclude that
the alleles for color and vision segregate independently during gamete formation
a testcross is
a mating between an individual of unknown genotype and an individual homozgous recessive for the trait of interest
a carrier of a genetic disorder who does not show symptoms is most likely to be _____ transmit it to an offspring
heterozygous for the trait and able
Dr. Smith's parents have normal hearing. However Dr. Smith has an inherited form of deafness. Deafness is a recessive trait is associated with the abnormal allele d. The normal allele at this locus associated with normal hearing is D. Dr. Smith's parents could have which of the following genotypes?
Dd and Dd
Which of the following statements best explains why dominant alleles that cause lethal disorders are less common than recessive alleles that cause lethal disorders?
most individuals carrying a lethal dominant allele have the disorder and die before they reproduce whereas individuals carrying a lethal recessive allele are more likely to be healthy and reproduce
the expression of both alleles for a trait in a heterozygous individual illustrates
Which of the following terms refers to a situation where a single phenotypic character is determined by the additive effects of two or more genes?
genes located close together on the same chromosomes are referred to as... genes and generally...
linked, do not sort independently during meiosis
linked genes generally
do not follow the laws of independent assortment
crossing over ... genes into assortments of ... not found in the parents
recombines linked, alleles
what is the normal complement of sex chromosomes in a human male
one X chromosome and one Y chromosome
what is meant by the statement that "male bees are fatherless"?
male bees develop from unfertilized eggs
any gene located on a sex chromosome
is called a sex linked gene
sex linked conditions are more common in men than in women because
men need to inherit only one copy of the recessive allele for the condition to be fully expressed
which plants in this figure must be all be heterozygous
purple flowered plants in the f one generation
the creation of offspring carrying genetic information from a single parent is called
which of the following statements regarding sexual and asexual reproduction is true
sexual reproduction is more likely to increase genetic variation than is asexual reproduction
with the exception of identical twins siblings who have the same two biological parents are likely to look similar but not identical to each other because the have
a similar but not identical combination of genes
virchow's principle, stated formally in 1858
every cell comes from a cell
which of the following statements regarding cell division is false
cell division is common in eukaryotes but rare in prokaryotes
which of the following statements regarding prokaryotes is false?
prokaryotic chromosomes are more comples than those of eukaryotes
sister chromatids are
tightly linked together at a centromere
eukaryotic cells spend most of their cell cycle in which phase?
which of the following occurs during interphase
cell growth and duplication of the chromosomes
the genetic material is duplicated during
the S phase
if the S phase were eliminated from the cell cycle, the daughter cells would
have half the genetic material found in the parent cell
the process by which the cytoplasm of a eukaryotic cell divides to produce two cells is called
looking into your microscope you spot a unusual cell. instead of the typical rounded cell shape the cell has a very narrow middle seperating two bulging ends. it sort of looks like the number 8! then you realize that this cell is
the phase of mitosis during which the nuclear envelope fragments and the nucleoli disappear is called
during which phase of mitosis do the chromosomes line up on a plane equidistant from the two spindle poles
at the start of mitotic anaphase
the centromeres of each chromosomes come apart
during which phase of mitosis does the nuclear envelope re-form and the nucleoli reappear
which of the following is a feature of plant cell division that distinguishes it form animal cell division
formation of a cell plate
which of the following must occur for a plant or animal to grow and develop normally
the organism must be able to control the timing and rate of cell division in different parts of its body
as a patch of scraped skin heals, the cells fill in the inquired area but do not grow beyond that. this is an example of
density- dependent inhibition
which of the following is probably the main factor responsible for the phenomenon for density dependent inhibition
availability of growth factors
mature human nerve cells and muscle cells
are permanently in a state of non division
the cell cycle control system is most like
the control device of an automatic washing machine
you are asked to culture an unidentified sample of animal tissue. you notice that the cells seem to fail to exhibit density dependent inhibition. the source of this tissue is most likely...
a benign tumor differs from a malignant tumor in that a benign tumor
does not metastasize
which of the following shoes the greatest promise as a cancer chemotherapy agent?
a drug that prevents tetrad formation
which of the following statements regarding the function of mitosis is false
mitosis allows organisms to generate genetic diversity
two chromosomes in the nucleus that carry loci for the same traits in the same position on the chromosome but specify different versions of some traits constitute a pair of
a pair of male human sex chromosomes is most like
a bride and a groom
which of the following statements regarding mitosis and meiosis is false
mitosis produces daughter cells with half the number of chromosomes as the parent cell
which of the following statements is false about haploid vs. somatic.
gametes are made by mitosis
during which stage of meiosis does synapses and the formation of tetrads occur
which of the following options correctly describe the behavior of a tetrad during anaphase one of meiosis
it splits into two pairs of sister chromatids and one pair goes to each pole of the divided cell
which of the following statements regarding the differences between mitosis and meiosis is false
crossing over is a phenomenon that creates genetic diversity during mitosis
both mitosis and meiosis are preceded by
independent oritentation of chromosomes at metaphse one and random fertilization are most like
shuffling cards and dealing out hands of poker
which of the following statements regarding genetic diversity is flase
genetic diversity is enhanced by mitosis of somatic cells
can reveal alterations in chromosome number
a karyotype is most like
photographs of every couple at a high school prom
which of the following statements regarding down syndrome is false
women with down syndrome cannot reproduce
nondisjunction occurs when
members of a chromosome pair fail to seperate
which of the following types of organisms commonly demonstrates polyploidy
which of the following variations of the sentence "whre is the cat" is most like a chromosomal deletion
where is cat?
if a chromosomal fragment breaks off and then reattaches to the original chromosome but in the reverse direction the resulting chromosomal abnormality is called
cancer is not usually inherited because
the chromosomal changes in cancer are usually confined to somatic cells
what type of cell is shown
plant cell in telophase