Plant Breeding and Genetics Certificate Program Pre-test

An organism that has the ‘Aa’ genotype…

Based on the genotypes given for the plant phenotypes shown in the figure below, select the correct answer.

Select the answer that best completes the following statement. One gene from each gene pair is found in…

In an inheritance experiment, a plant with the normal green phenotype and the genotype Gg is self pollinated to produce offspring. The offspring of this cross consisted of ¾ with the normal green phenotype and ¼ with a pale green phenotype. The ratio of homozygotes to heterozygotes among the normal, green F2 individuals is…

In an inheritance experiment, F3 seeds from 18 F2 plants with the dominant or normal trait were planted in 18 rows. Eight rows had all normal plants and 10 rows had both normal and disease lesion plants. The number of homozygous plants among the 18 normal F2 plants was…

Choose the option that best completes the following sentence. The principle of segregation states that…

An abstract by Ng et al (2004, Weed Science v52, no4, p. 564-570) states: “The inheritance of glyphosate-resistant goosegrass was studied by making reciprocal crosses between resistant (R) and susceptible (S) biotypes. Eighty-four F1 hybrids were confirmed using isozyme analyses. Reciprocal F1 hybrids displayed uniform levels of resistance intermediate (I) to that of the parental types, with no indication of maternal inheritance. The F1 hybrids were selfed to produce F2 populations. F3 populations were produced by selfing resistant and intermediate F2 phenotypes. A segregation ratio of 1:2:1 (S:I:R) was observed in the F2 and subsequently in the F3 generations derived from selfing intermediate F2 phenotypes. Individuals in F3 families derived from selfing resistant F2phenotypes were resistant.”
Their results show that…

With ALS herbicide-resistant corn, the IR allele controls resistance but has a lack of dominance to the IN allele. Predict which would be true of the offspring from the cross: IRIN x IRIN

Which type of cross will be used to determine if cytoplasmic inheritance is involved with volunteer corn genetics?

F2 seeds from a crossing experiment are grown in hot temperature. Scoring of plant leaf color revealed a ratio of three green to one yellow among the F2 plants. A second sample of eight F2 seeds from the same experiment were grown in cooler temperatures resulting in a ratio of one dark green plant to two pale green plants to one yellow plant (1DG:2PG:1Y). These results are an indication that…

A round, green F2 seed is selected from the cross in the table below. It is planted and the resulting plant is allowed to self pollinate. What is the probability that a randomly selected F3 seed from this plant will be round and green?

Assume that A,a and B,b gene pairs are independently assorting. An individual that has the genotype AaBb can make…

The combination of leaf color and leaflet number phenotypes observed in the F2 data shown would be considered what ratio?

Assume that the Aa, Bb, Dd, Ee, and Ff gene pairs influence a quantitative trait with each upper case allele adding the same amount to the trait. The lower case alleles do not add to the trait. An individual with the genotype AaBbDDEeFf is selfed. Which of the following is the best description of the phenotypes that will be observed among the progeny resulting from this cross?

The broad sense heritability for trait A is 0.85 while the broad sense heritability for trait B in the same population is 0.25. Variation in which trait is most influenced by genetic variation?

A tall plant is crossed with a short plant and the offspring are all medium in height. Based on this result…

Bread wheat, an allohexaploid, has the same basic chromosome number of n=7 from each of the progenitor genomes in this polyploid. How many chromosomes will be present in the pollen cells of bread wheat?

Seedless watermelons cannot complete meiosis. Which of the following would be a likely description of seedless watermelon?

When Durum wheat was being created, a hybridization between 2 different species, each with 7 chromosomes in it’s gametes, was formed. Why was this original hybridized new species sterile, even though it had 14 total chromosomes?

Below are descriptions of four events. Select the choice that lists three of these events in the order they would occur as a population of plants evolves.
A. A change happens in the ecosystem environment
B. A mutation occurs at random in the genome of a plant and this random mutation is passed on to offspring.
C. Individuals with one genotype are more reproductively successful than individuals with a different genotype at that gene pair.
D. A change in the environment causes a mutation to occur in a specific gene.

Assume that there are two alleles in the gene pool of two different populations, the ‘H’ allele and the ‘h’ allele. The frequencies of the HH, Hh and hh genotypes in each population are shown in the table below.
                                 HH     Hh     hh
Population W     .09      .18      .81
Population Z       .16      .48      .36

Which of the populations appears to be randomly mating with respect to the ‘H’ and the ‘h’ allele?

An individual with the genotype AaBb is crossed with an aabb individual and offspring with the following genotypes are produced:

Based on the offspring data the A,a and B,b genes in the AaBb parent are found at…

The F,f and G,g loci are 10 map units (centimorgans) apart.  The following crosses are made:

FFGG X  ffgg  produced offspring that were FfGg. These FfGg offspring were crossed with ffgg.

A breeder can easily select offspring of the FfGg X ffgg cross above based on their Ff or ff genotype. However, the offspring they most want to select will have the genotype gg and that is a difficult trait to select.

Choose the best decision for the breeder based on the genetic story above and their desire to select plants that are gg and discard Gg plants.

The following events happen inside of a plant cell:

A. Ribosome binds to the start codon

B. tRNA binds to a codon

C. RNA polymerase binds to the promoter

D. Newly made protein folds into a specific shape.

Select the choice that places these four events in their correct order in the gene expression process.

A mutation occurs in the exon sequence of a gene just after the start codon.  Which mutation will have the biggest impact on the sequence of amino acids encoded by this gene?

ALS herbicide resistance in a plant is controlled by the I^R  allele of the gene that encodes an enzyme which is the active site of the ALS herbicides.  Which choice below explains why there is a lack of dominance of the I^R  and I^N  allele so the I^RI^R  plants have high levels of resistance, I^RI^N  plants have some resistance and  I^NI^N have no resistance to an application of ALS herbicide?

Assume a plant breeder performs marker-assisted selection on the DNA in seeds in order to increase the efficiency of their breeding program.  They perform these operations:

A. Set up a PCR reaction.

B. Run an electrophoresis gel or sequence selected fragments of the plant genome

C. Isolate DNA

D. Collect a tissue sample

Select the choice below that is the correct order of these operations.

What cellular process is the PCR reaction based upon?

Question 29.

Assume a team of scientists conducts the following operations.

A. Backcross breed an elite parent as the recurrent parent with a plant that has a new transgenic event.

B. Isolate DNA from the organisms that naturally possess the genes that will make the transgene.

C. Transform the transgene into plant cells using tissue culture and clone plants from the Petri dishes that have the transgene.

D. Design the transgene.

Select the choice below that is the correct order of these operations.

Below are four types of genetic modifications:

A. Creating a new polyploid by adding cholchicine.

B. Creating mutations by the addition of a chemical that creates additions and deletions.

C. Creating a transgenic plant.

D. Creating a gene-edited plant.

Select the choice below that is the correct order of these, from the modification that makes the smallest genetic change to the biggest genetic change.