EXAM 3 Flashcards
whether an allele is dominant or recessive depends on
A which chromosome it is on
B whether it is inherited from the mother or father
C whether or not it is linked to other genes
D ho common an alle is relative to other alleles
E whether it or another allele determines the phenotype in the heterozygote
E whether it or another allele determines the phenotype in the heterozygote
the phenotype of an individual
depends at least in part on the genotype
father has type O mother has type AB what blood types could their children have
Children could have blood types A or B
a test cross is used to
determine whether an organism expressing the dominant phenotype is homozygous or heterozygous
in humans brown spotting of teeth is caused by a dominant X-linked gene id a man with brown teeth married a woman with normal teeth ……
all of their dughters would have brown teeth
ABO blood groups are an example of
COdominance
coat color in Labrador retievers is an example of
epistasis
all the offspring of a white fox and black fox are all greay the simplest expleanation for this pattern of inheritance is
incomplete dominance
a woman with hempopilia marries a normal man which of the following would best describe their children
A. their daughters will be hemophilic their sons will be normal
B their daughters will be normal their sons will be hempphelic
C all their daughters and sons will be carriers
D all daughters will be normal and 1/2 sons will be hemophilic
E all children will be hemophilic
B their daughters will be normal theirs sons will be hemophilic
which of the following human traits is caused by non-disjunction
A xxy( klinefelters syndrome) B downs sydrom C sickle cell disease D hemophilia E both A and B
E both xxy( klinefelters syndrome) and downs syndrome
which of the following human traits is caused by an autosomal dominant alle
huntingtons disease
CcDd is crossed with CcDd what fraction of the offdpring are expected to have the first gene and the ressve pheno type for the second gene
3/16
cystic fibrosis is an autosomal rescessive disease in one family bth parents are heterozygous and they have two children what is the probabloity that both children are normal
9/16
why are some phenotypes complex
the phenotype is affected by the environment and is determined by multiple genes
grffiths studies of streptococcus pnemoniae
demonstrated the phenomenon of bacterial transformation
one strand of DNA has the sequence of 5’-GAACG-3’ the complementary strand for this
5’-CTTAGC-3’
what kind of damage does uv light cause to DNA
produces thimine dimers
okazaki fragments are
joined together with helicase
telomerase contains an rna sequence that acts as a template
true
whose experiments showed that DNA replication is semiconsorvative
meleson /stahl
which of the following best describes the flow of information( central dogma) within the cell
DNA–>RNA–>protein
which kind of RNA contains the information which specifies the amino acid sequence of a protein
mRNA
which of the following enzymes can synthesize a strand of rna
DNA polymerase and rna polymerase
what is the function of the enzymes known as aminozcyl tRNA synthetase
they put amino acids on the tRNA
what contribution did rosalind franklin make to the discovery of the structure of DNA
she performed the X-ray crystaliography
where does transcription begin
at the promoter
ribosomes are composed of
a few proteins and four rRNA molecules
what is the name of the enzymes that unwinds the double helix of DNA
helicase
what cause sickle cell disease
a missense mutation
what is the result when hologous chromosomes break at differnt positions and swap segments
deletion and duplication
the PCR reaction
amplifies specific DNA sequences
in PCR double stranded fragments of DNA are seperated into single strands by
heating
what happens when a dedoxyiribouleotide is added during a DNA sequence reaction
synthesis on that DNA strand stops
which of the following is a technique used to separate DNA molecules of differnt sizes
electrophoresis
which of the following techniques would be most useful for quickley determing the identity of a drop of blood
PCR
viruses are obligate intracellular parasites
true
individuals with xeroderms pigmentosym are very sensitive to uv light why>
theyre excision repair mechanism does not work properly
bacteriophage are bacteria that eat other bacteria
false
what is the genetic material of viruses
DNA single or double or rna single or doubel
why do people need to get caccinated against influenza every year
the influenza virus changes from year to year
hiv is a
retrovirus
some bacteria can transfer DNA from cell to another through a tube called sexy pilus what is this process called
conjugation
some bacteria can pick up DNA from their environment usuallly from cells that have died what is this process called
transformation
proteins are synthesized starting from the C terminus and finishing at the N terminus
false
peptidyl transferase activly is found in a molecule of tRNA
true
bacteria are usally haploid
true
a virus enters a bacteria cell and inserts a copyu of its genetic material into the host
the lysogenic cycle
the simplest virsuses are composed of which of the folowing
capsid proteins and nucleic acid
what enzymes produce the genetic material inside HIV
reverse transcriptase
bacteriophage lambda infects a cell and makes lots of cl protein and little cro proteins what happens
a lysogenic cycle
what is a wobble
altered rules for base pairing between codon and anticodon
what is a signal sequance
it indicates where a protein should go
what happens to proteins after translation
some proteins are modified by the addition of sugars and some proteins are modified by the addition of phosphate groups
which of the following statments about HIV is False
a. HIV has a high mutation rate
b. Infection by HIV results in the destruction of helper T cells
c. Reverse transcriptase, protease, and integrase are required for HIV replication
d. HIV is surrounded by an envelope containing glycoproteins
e. Reverse transcriptase uses RNA as a template to synthesize DNA in the nucleus
reverse transcriptase usses RNA as a template to syntesize DNA in the nucleus
influenza virus does not contain a viral envelope
true
mendels experemnts support the blending theory of inheritance
false
an individual pea plant is both male and female
true
what did mendel discover from his monohybrid crosses
segregation of alleles
what did mendel discover when he performed dihybrid crosses
independent assortment
when a single allele has more than one distinguishable phenotypic effect the alle is
pleitropic
we learned about an experimentwhere a cell in sphase was fused to a cell in G1 phase of the cell cycle what happened
the g1 phase nucleus began DNA replication
when does DNA replication occur in eukaryotic cells
during interphase
before s phase each chromose contains onkly one double stranded dna molecule
true
when do chromosomes line up on the equater in mitosis
metaphase
when do chromosomes become visable during mitosis
prophase
when does dna synthesis take place in eukaryotes
s phase
which of the following is a type of protein that wraps around to form beads on a string
histone
before a cell can leave G1 and go to s of the cell cycle
RB protein must be phosphorlated by a Cdk
in meiosis
homologous chromosomes separate from one another in anaphase I
when does crossing over occur
prophase I
what kind of cells divide by mitosis
eukaryotic cells
when does cytokenisis usually begin
during telophase
which of the following is not a function of mitosis
production of gametes
growth
asexual reproduction
cell replacement
repair of damaged organs
production of gametes
how many chromosmes would be found in a normal human somatic cell during interphase
46
the special cells that produce gamets in animals are called
germ cells
during meiosis sister chromatids f each cromosome moce apart during
anaphase II
the spindle is made of _________ and attatches to the _____________
microtubles, kinetochores
sometimes chromosomes fail to separate properly during meiosis what is this process
nondisjunction
what kind of sexual life cycle do most anuimals have
diplontic
what kind of sexual life cycle do most plants have
alternation of generations
What does HIV stand for
human immunodeficiency virus
what does PCR stand for
polymerase chain reaction
the ends of chromosomes are called
telomeres
Dominant
always shows T
recessive
needs two copies to show t
homozygous
has two of the same either TT or tt
heterozygous
has one of each Tt
genotype
genetic makeup
phenotype
physical characteristics
What is rob protein
A tumor suppressor
WHen does DNA replication occur in eukaryotes
During interphase
What is p 21
A protein that weighs 21000 daltons
What is cytokinesis
When a cell divides in two
A patient odiscovers an unusual growth and goes to the doctors which diagnosis means that the growth is spreading
Metastasis
A virus infects the cell and inactivated retinoblastoma protein what will happen next
Cell leaves g1 and goes to s phase
How do prokaryotic cells divide
Binary fission
Cell in s phase fused to G 1 phase what happens
G1 phase nucleus begin DNA replication
