WorksheetsJanuary 1997 Diploma Exam
Total questions: 55
Worksheet time: 2hrs 50mins
A likely explanation of how receptors in the human brain are stimulated by opiates is that opiates
bind to neurotransmitters
act in the same way as cholinesterase
increase the strength of action potentials
have molecular shapes similar to neurotransmitters
The neuron in an experiment is taken from a spinal cord. The propagation of an action potential in the neuron was slower than the 24 m/s that is typical with sensory neurons. Why?
Myelination was absent in this spinal neuron
Axon length is much longer in sensory neurons
The Nodes of Ranvier were absent in sensory neurons
The neurotransmitters were blocked in this spinal neuron
The voltmeter showed a negative reading and the sodium ion concentration remained constant outside the axon. How could this be explained?
The threshold for the neuron was not reached
The sodium pump had exhausted ATP reserves
The action potential was established and sustained
The dendrites were stimulated by release of acetylcholine
In a resting neuron, the outside of the cell membrane is
positive, and the sodium ion concentration is greater in the fluid outside the axon than in the cytoplasm
negative, and the sodium ion concentration is greater in the fluid outside the axon than in the cytoplasm
positive, and the sodium ion concentration is greater in the cytoplasm than in the fluid outside the axon
negative, and the sodium ion concentration is greater in the cytoplasm than in the fluid outside the axon
Which correctly identifies the most likely location of lesions in each disease?
Location of lesions in fatal familial insomnia: cerebellum
Location of lesions in Creutzfeldt/Jakob disease: hypothalamus
Location of lesions in fatal familial insomnia: medulla oblongata
Location of lesions in Creutzfeldt/Jakob disease: hypothalamus
Location of lesions in fatal familial insomnia: cerebellum
Location of lesions in Creutzfeldt/Jakob disease: cerebrum
Location of lesions in fatal familial insomnia: medulla oblongata
Location of lesions in Creutzfeldt/Jakob disease: cerebrum
The mutated DNA triplet 178 would be transcribed to the mRNA codon
AAC
TTG
UUG
GAC
What are the structures that are responsible for the production of the components of semen (in lowest-to-highest numerical order)?
(a)
The structures that are directly affected by hormones secreted from the pituitary gland are structures
6, 9, and 10
9, 10, and 13
8, 10, and 11
8, 11, and 13
What point on the diagram is best matched with the correct event?
Point 1 - ovulation
Point 2 - menstruation
Point 3 - formation of the follicle
Point 4 - formation of the corpus luteum
Provide the sequence of numbers for the terms that would correctly complete the following statement:
During human fertilization, ____ gametes produced by ____ unite to form a ____ zygote that undergoes ____ to form a fetus.
(a)
Which hormone, if given to the egg donor, would promote the growth and development of ova?
LH
FSH
Estrogen
Progesterone
During the process of implantation, the enzymes secreted by the
ovum digest the zygote membrane
sperm digest the zygote membrane
blastocyst digest a portion of the endometrium
blastocyst digest a portion of the corpus luteum
If a substance was present in the embryo that inactivated the MIH hormone, males babies would be born with
female reproductive ducts and male sex chromosomes
male reproductive ducts and female sex chromosomes
male reproductive ducts and female secondary sex characteristics
female reproductive ducts and female secondary sex characteristics
Which is a logical inference derived from this information?
Male and female embryos would be anatomically similar at one stage of their development
The genital ridge would continue to secrete sex hormones during the remaining seven months of pregnancy
Injection of large quantities of testosterone into a pregnant female would change the sex chromosomes of the developing embryo
Injection of large quantities of estrogen into a pregnant female would enhance the development of existing sex organs in the embryo
The increasing level of HCG from the time of fertilization until week 8 serves to
maintain the function of the corpus luteum
determine the sex of the developing embryo
inhibit the development of the endometrium
direct the processes of ovulation and fertilization
Removal of the mother's ovaries before the seventh week of pregnancy leads to a miscarriage. After 12 weeks, removal of the ovaries usually has no effect on pregnancy. An explanation for these observations is that
after 12 weeks, the endometrium is easily shed
after 12 weeks, the placenta maintains the pregnancy
the follicle remains well developed for at least 12 weeks
implantation is not firmly established until the 12th week
Sequence the events that occur during breast feeding.
(a)
Which hormones would be used in the hormone therapy treatment of endometriosis?
FSH and LH
LH and estrogen
FSH and progesterone
Progesterone and estrogen
The process of fertilization would be directly affected by scarring resulting from endometriosis in structure
1
2
3
4
At puberty, the LH in the human male directly
inhibits the production of sperm
stimulates the production of testosterone
causes the growth of facial and body hair
stimulates the maturation of the seminiferous tubules
The two point-mutations in DNA that would change the code for oxytocin to ADH occur
at 1, where T would be replaced by A
at 2, where A would be replaced by C
at 1, where A would be replaced by T
at 2, where C would be replaced by A
at 1, where U would be replaced by A
at 2, where U would be replaced by G
at 1, where U would be replaced by A
at 2, where G would be replaced by U
If a pregnant woman failed to produce oxytocin, what would be the result?
Urination would be more frequent
ADH levels in the bloodstream would drop
Uterine contractions would not begin for labour
Oxytocin levels would increase in the bloodstream
Although the adenine base composition of DNA from the above organisms is very similar, these organisms vary greatly in their characteristics. The cause of this variation is that the DNA molecules of the respective organisms contain different
pairings of nitrogen bases
sugars in their nucleotides
sequences of nitrogen bases
proteins in their nucleotides
Which correctly identifies processes 1 and 2 and indicates the locations in which these processes occur?
Process 1: transcription - nucleus
Process 2: translation - cytoplasm
Process 1: translation - cytoplasm
Process 2: transcription - nucleus
Process 1: translation - nucleus
Process 2: transcription - cytoplasm
Process 1: transcription - cytoplasm
Process 2: translation - nucleus
Using the DNA sequence TCAGGA, the dipeptide formed is
threonine, glycine
threonine, proline
serine, proline
serine, glycine
Which correctly identifies the enzyme-directed processes 1, 2, and 3?
Process 1: ligase
Process 2: restriction enzymes
Process 3: ligase
Process 1: restriction enzymes
Process 2: restriction enzymes
Process 3: ligase
Process 1: ligase
Process 2: ligase
Process 3: restriction enzymes
Process 1: restriction enzymes
Process 2: ligase
Process 3: restriction enzymes
Which statement about the DNA fragments on the gel plates is correct?
Band 1 has more base pairs than band 5
Band 3 has more base pairs than band 2
Band 1 has the least number of base pairs
Band 5 has the largest number of base pairs
The use of this new technology is valuable for the conviction of criminals because, with the exception of identical twins, every individual is unique with regard to the
type of nucleotides found in DNA
type of proteins produced by DNA
protein sequence in some segments of DNA
nucleotide sequence in some segments of DNA
The process that occurs during interval K-L is
cytokinesis
chromatid separation
replication of genetic material
synapsis of homologous chromosomes
On the graph, N likely indicates the completion of which mitotic event?
Prophase
Anaphase
Telophase
Metaphase
On the graph, interval N-P corresponds to the period between the end of
mitosis and the beginning of stage 1
stage 2 and the beginning of stage 3
stage 1 and the end of stage 2
stage 1 and the end of mitosis
One difference between mitosis and meiosis is that, during mitosis,
One replication of chromosomes and one division occurs
One replication of chromosomes and two divisions occur
Two replications of chromosomes and one division occurs
Two replications of chromosomes and two divisions occur
Starting from a single cell, spermatogenesis in horses produces
one cell with 33 chromosomes
two cells, each with 66 chromosomes
four cells, each with 33 chromosomes
three cells, each with 22 chromosomes
A human with Klinefelter syndrome has 47 chromosomes and has the XXY chromosome set instead of XY. From what does this abnormality result?
The process of mitosis does not occur properly
An error in replication produces an extra X chromosome
Crossing over results in the formation of an extra chromosome
Nondisjunction occurs in either the formation of the sperm or the egg
The fact that the Dionne Quintuplets were identical indicates that they developed from
one ovum that was fertilized by five different sperm cells
five separate eggs that were released from an ovary simultaneously and then fertilized
one zygote that split into five separate surviving embryos during initial mitotic divisions
one ovum that underwent mitosis to produce five eggs, each of which was fertilized by one sperm cell
In the F1 generation, the allele for yellow seeds would have been found in
about 50% of the female gametes and 50% of the male gametes produced by F1 plants
all of the female gametes and none of the male gametes produced by F1 plants
all of the male gametes and none of the female gametes produced by F1 plants
none of the male gametes or female gametes produced by F1 plants
The phenotypic ratio of a cross between YyTt pea plant and a yyTt pea plant is
3 yellow tall : 3 yellow short : 1 green tall : 1 green short
1 yellow tall : 1 yellow short : 1 green tall : 1 green short
3 yellow tall : 1 yellow short : 3 green tall : 1 green short
1 yellow tall : 1 yellow short : 3 green tall : 3 green short
In a cross between a RrYy and a RRYY plant, what fraction of the offspring would be expected to have the genotype RRYy?
1/2
1/4
3/8
1/8
What percentage of the gametes (as a whole number) produced by a pea plant heterozygous for both seed shape and seed colour would be expected to contain both the allele for wrinkled and the allele for green? (a) %
Which pattern of inheritance for flower colour is demonstrated by this sweet pea plant variant?
X-linked recessive
Autosomal recessive
Autosomal dominant
Incomplete dominance
Analysis of a DNA sample from the nuclei of the purple flowers determined that the thymine content of the nucleotides in the DNA was 23%. What is the likely content of adenine, cytosine, and guanine in the DNA?
Adenine: 23%
Cytosine: 27%
Guanine 27%
Adenine: 23%
Cytosine: 27%
Guanine 23%
Adenine: 27%
Cytosine: 23%
Guanine 23%
Adenine: 27%
Cytosine: 23%
Guanine 27%
A man who is heterozygous for the disease allele marries a woman who is homozygous for the normal recessive allele. What is the probability that their first child is a boy and has Huntington's disease (as a value from 0 to 1, rounded to two decimal places)?
(a)
Of the following, the parent and child combination that could be possible is
parents 1 and baby Y
parents 2 and baby Z
parents 3 and baby W
parents 4 and baby X
The probability (from 0 to 1, rounded to two decimal places) that a mother with blood type O and a father with the genotype IBi would have a child with blood type O is (a) .
A colour-blind male with brown eyes and his green-eyed wife who has normal colour vision have a daughter who is colour-blind and has blue eyes. What is the genotype of this child?
XcbXcbBb
XcbXcbGb
XcbXcbbb
XcbYbb
If individual 1 has blue eyes, genotypes of her parents could be
mother XXbb, father XcbYGB
mother XXcbGb, father XYbb
mother XcbXcbGG, father XYbb
mother XXcbGb, father XcbYBB
Three genes have been identified on chromosome 2 in Drosophila (fruit flies). They control eye colour, body hair (bristles), and wing shape. The genes are:
1 cinnabar eyes
2 short bristles
3 curved wings
The crossover frequency between 1 and 3 is 18%, between 2 and 3 is 24.5%, and between 1 and 2 is 6.5%. Construct a gene map of three genes and indicate their order by number.
(a)
This information indicates that the genotype for the unknown male is likely
homozygous
heterozygous
either homozygous recessive or heterozygous
either homozygous dominant or heterozygous
The gene pool of Drosophila is affected by the Sd allele because this allele
produces new gene combinations
increases genetic diversity
favours natural selection
increases in frequency
If a researcher samples 10 000 Drosophila from this population, the number of flies expected to by homozygous dominant for body colour is
400
3200
6400
9600
These relationships are not applicable when there is
a large population size
absence of migration from a population
random mating between members of a population
selection against a particular genotype in a population
If a change in the environmental conditions in western Africa caused an increase in the mosquito population, what would likely happen to the frequencies of the alleles HbA and HbS?
The frequency of both alleles would increase
The frequency of both alleles would decrease
The frequency of the HbA allele would increase and the frequency of the HbS allele would decrease
The frequency of the HbA allele would decrease and the frequency of the HbS allele would increase
The relationship between humans and Plasmodium falciparum is called
parasitism
mutualism
competition
commensalism
The presence of eyespots on the wings of butterflies is an example of
mimicry
mutualism
camouflage
competition
The relationship between the barnacles and the whales is one of
predation
parasitism
mutualism
commensalism
