Plant Science 131 Part 3
When a scientist publishes their research in a scientific journal they include their materials and methods in order to...
...allow other scientists to repeat their experiments to either confirm their results or address new questions.
When new technologies are developed and used in growing plants...
...the general public or the grower who uses the products should be confident that products are safe to use and have the effect described in the product label.
Two plants with the genotype GG are crossed. How many kinds of offspring can they produce with respect to the G and g genes?
1
Two plants with the genotype gg are crossed. How many kinds of offspring can they produce with respect to the G and g genes?
1
Two plants with the genotype gg are crossed. How many kinds of offspring can they produce with respect to the G,g genes?
1
Place the correct term in the appropriate location on the concept map.
1 : Adapt 2 : Evolve 3 : Individual 4 : Non-genetic 5 : Population 6 : Genetic 7 : Selection pressure 8 : Environmental change 9 : Genetic variation 10 : Successful reproduction
Place the correct term in the appropriate location on the concept map.
11 : Cross pollination 12 : Maximum genetic diversity 13 : Self-pollination 14 : Low genetic diversity 15 : Perfect 21 : Imperfect 22 : Dioecious 23 : Monoecious
Place the correct term in the appropriate location on the concept map.
16 : Bud dormancy 17 : Seed dormancy 18 : Stomatal regulation 19 : Fruit ripening 20 : Cell death and senescence
How many stamens are pictured in the perfect flower?
3
Two plants with the genotype Gg are crossed. How many kinds of offspring can they produce with respect to the G and g genes?
3
A plant with the genotype AaGg makes pollen. How many different kinds of pollen with respect to the A,a and G,g genes can this plant make?
4
According to the two Punnett Square diagrams, an AaBb plant that is self-pollinated will make how many different kinds of genotypes among its offspring?
9
Place the correct term in the appropriate location on the concept map.
9 : Carbohydrate 17 : Oils 18 : Proteins 19 : Amino acids
What is apical dominance?
A plant that has growth primarily from the apical buds and suppresses growth from axillary buds.
What conclusion(s) did Darwin's experiment support?
A. Hormone (auxin) that controls cell elongation is made in the tip C. Light controls how the hormone (auxin) is made or travels
The corn seeds below have a shrunken look because....
ALL of the above are correct.
How will a hormone help a plant control its growth?
ALL of the above are reasons why hormones can control plant growth.
This is the best conclusion
Auxin applied at the shoot tip controls apical dominance, and not cytokinin
Assume a strong wind blows down the tall castor bean plant in the teaching garden. Predict how the plant will respond.
Auxin produced from dominant apical bud will move more on the dark side of the stem that is on the ground. This will induce these cells to elongate more and the plant will bend upward.
This experiment was done in the dark. Predict the growth response (if any) from each experiment.
B. Coleoptile curves to the right in both
Select the conclusions that Boysen and Jensen's experiment support.
B. Hormone (auxin) that controls cell elongation travels on the dark side of stem E. Hormone is a chemical substance that can move into and out of the plant coleoptile cell
Bt proteins can be applied to crop or garden plants to protect against insect damage. The insect larvae will consume the Bt proteins if they feed on the plant and could die if they consume enough of the protein. The reason transgenic Bt places more selection pressure on the insect populations is...
Both b and c above (the two previous statements) are correct and contribute to transgenic Bt placing more selection pressure on insect populations than an application of Bt protein.
Why should we be concerned about the possibility of transgene escape?
Both c and d
Assume you are an USDA scientist. Based on all the data, what is your recommendation on the use of Bt. corn in the Monarch flyway?
Bt corn can be grown without restrictions based on the ecological interaction between this plant and monarch larvae. There will rarely be toxic levels of the Bt pollen encountered based on the high dose needed for minimum lethal dose and the extremely rare occurrence of that dose.
Based on the hypothetical results presented in the figure, what conclusion is supported?
Bt pollen is not lethal but beneficial, promotes growth!!
How do plants sexually reproduce?
By making seeds.
What 'action' must Primo Maxx have to provide the growth regulation desired by turf managers ?
C. BLOCKS the enzyme that works at #2
Betty is in charge of weed control on the family farm. She rotates fields with wheat, soybean and corn. She uses an herbicide with a different mode of action to kill weeds in each crop. Weed control on the farm to the east is managed by DJ. He really likes to use glyphosate so he grows glyphosate resistant soybean in one year then rotates to glyphosate resistant corn, then back to soybean. Whose farm is most likely to produce a glyphosate resistant weed?
DJ because always applying the glyphosate to kill weeds and always delivering toxic doses and this places continuous selection pressure on the weeds to exploit naturally arising genetic variation for resistance.
DNA is a stable biological molecule. Evidence of this stability is the fact that...
DNA can be removed from a cell, put in a test tube then put into a new cell and the molecule retains its ability to code information.
Identify the name of the seed structure where cellulose is made during germination.
Embryo
Why does banana #1 (very green) ripen faster when placed in a brown paper bag with banana #8 (very ripe)?
Ethylene is a gas at room temperature.
Once resistance evolves in a population of insects, resistance alleles can move to other populations as the adults migrate to find mates. Which insect populations will tend to spread resistance faster and or farther once resistance arises?
European corn borer (moths are the adults)
What would be the order of the steps shown below that would be used by genetic engineers and plant breeders to make genetically engineered pumpkins with a cotton gene for making cotton fiber filled fruit?
Extract all the genes from a cotton plant tissue Isolate and clone the cotton fiber gene Modify the cotton gene to turn on in pumpkin fruit Insert this gene into pumpkin cells, clone a pumpkin plant from these cells Breed this transgenic plant with other pumpkins
Which of the growth patterns below would describe a trait that would give a weed a selective advantage over other weeds growing in a yard that is mowed every five days.
Flowering low to the ground.
A difference between a hormone and a growth regulator is...
Hormones are made by the plant, growth regulators are made by people.
Buffalograss breeders can improve resistance by making crosses and selecting offspring. Buffalograss is dioecious. How will breeders need to manipulate the buffalograss (no space) flowers in order to cross a moderately resistant plant with a moderately susceptible plant?
Just put the two plants, a male and a female, in the same greenhouse at the same time.
Both farmers are using Bt cotton. Cotton farmer Katie plants a 20% refuge of non-Bt cotton. Her cousin Kal plants a 10% refuge. Who is applying the most selection pressure to the insect pests of cotton that the Bt proteins target?
Kal
Propose how one could make a grass coleoptile grow in the shape of an S.
Leave the tip on the coleoptile and then have light shine on the coleoptile from the side, then gradually move the light over to the other side.
Select the best conclusion from the GA application experiment.
Mutant cannot make GA, perhaps the mutation is in a GA synthesis enzyme.
What term describes the relationship between transgenic Bt corn and the Monarch?
None of these, but Bt corn might endanger Monarch populations.
Based on the results presented in the figure, what is the hypothesis of the field study test?
Pollen dose is related to distance from the field
Why is the replication of the chromosomes in the organisms cell a necessary part of growing with mitosis cell division?
Since the A,a,B and b genes are a part of chromosomes, the chromosomes must be replicated so all the cells get the same genetic information.
The step in the pathway diagram below that would represent adding a growth regulator that induces more shoots to develop from a plant cutting.
Step 1
What step in the pathway shows where a growth regulator application removes 'control' of growing point and results in uncontrolled stem growth?
Step 2
What pathway step shows where a growth regulator works to cause cotton leaves to fall off plant before a frost?
Step 3
What pathway step shows where a mutation allows seeds to germinate on the mother plant?
Step 5
What pathway step shows where a growth regulator inhibitor works to suppress growth and make turfgrasses shorter?
Step 7
Seeds contain a new plant (embryo).
TRUE
A wheat breeder uses naturally occurring genetic variation to breed herbicide resistance into new wheat varieties since no transgenic traits have been approved in wheat. A corn breeder has the option of crossing genetically engineered herbicide resistant corn plants with their best parent lines to make a new hybrid. A true statement is...
The amount of selection pressure placed on the weeds by continued use of the herbicide is more important than the way genetic resistance was incorporated into the crop plant.
A wheat breeder uses naturally occurring genetic variation to breed herbicide resistance into new wheat varieties. A corn breeder crosses genetically engineered herbicide resistant corn plants with their best parent lines to make a new hybrid. The correct statement is...
The amount of selection pressure placed on the weeds by continued use of the herbicide is more important than the way genetic resistance was incorporated into the crop plant.
Seedling E below has a cap placed on the tip of the coleoptile. Light cannot penetrate the cap and provide a light signal to the coleoptile tip. Predict what will happen because of this 'cap' treatment.
The cap prevents the plant cells from sensing the direction of light and sending auxin traveling down the dark side of the stem. The shoot will grow straight up.
Which of the statements below is a conclusion from the cross depicted by the Punnett square above?
The diagram depicts possible results from a cross-pollination.
Bats visit flowers at night, collect nectar and cross-pollinate the plants. Some birds do the same during the day. An ecosystem has many more bats than birds one year. What would a plant biologist expect to observe if either birds or bat visits were required for seed production in this plant and night vs. day flower blooming was genetically controlled?
The frequency of night flower blooming in the plant population would increase the year after an abundant bat year.
Based the on actual data presented in the figure, what conclusion is supported?
The minimum dose of Bt pollen needed for a measurable decline in larvae growth is > 1600, maybe much greater!
Which cultivar (genetic type) of wheat is more likely to lodge (fall down) if there is a wind storm BEFORE harvest?
The one on the right
Which of the below describes why we would classify a corn plant as monoecious.
The plant makes both male and female flowers on the same plant, even though they are in different structures at different locations of the plant.
What is the purpose of a refuge for pesticide resistance management?
The refuge allows some members of the population to live their life without encountering the pesticide.
By removing the coleoptile tip as shown in seedling shoot D...
The seedling will not be able to be phototropic and respond to light direction because it cannot make auxin.
How is the popcorn seed different from normal starchy corn seed?
There is a layer of very hard, water tight endosperm and pericarp surrounding endosperm cells that contain water.
Based on the results presented in the figure, what hypothesis did this lab study test
There is a minimum lethal dose of pollen needed to kill monarch larvae
The motivation for reducing selection pressure on an insect population with a particular pesticide such as the Bt proteins is...
This helps the Bt work better in the long term
The planting plan below shows the farmer is planning a 10% refuge. What would be the impact of this planting plan on the rootworm population relative to the 'standard' of a 20% refuge of non-BT corn in the field?
This plan puts MORE selection pressure on the population compared with the 20% refuge.
If a plant breeder wanted to select cultivars that would be putting the least selection pressure on the insect population to change, they should select for...
Tolerance
There are six pollen cells shown in the picture. Where did these pollen come from?
Tricky question, corn plants make and spread pollen in their male flowers so the pollen in the picture could come from either the same plant or from a different plant.
A seed is alive.
True
Assume that in the picture below European corn borer (ECB) are living in a field that was planted to a corn hybrid that made a Bt protein toxic to ECB. The only ECB that are able to survive when they take a bite of this kind of corn are those that are homozygous for allele Z. Based on the occurrence of XX, XZ and ZZ ECB in the population, how well will the Bt trait in corn work in controlling this pest?
Well. All or most of ECB would die
Is the coleoptile (tip of the oat shoot) shown in B below making auxin?
Yes, auxin is made in the meristem at the tip of the coleoptile.
Assume that in the picture below European corn borer (ECB) are living in a field that was planted to a corn hybrid that made a Bt protein toxic to ECB. The only ECB that are able to survive when they take a bite of this kind of corn are those that are homozygous for allele Z. The ECB that will survive in the population will be the genotype...
ZZ
Penstemon have perfect flowers. The female part of the flower is ready to accept pollen two days before the male parts of the same flower produce pollen. The female can accept pollen for four days. This means...
a cross can be made to a penstemon flower by removing the male part of the flower, then adding pollen from a different male flower part on the same day.
A high level of selection pressure is place on the European corn borer population depicted in the picture, and only ECB that are ZZ survive. If the same level of selection pressure is placed on the next generation of this population, what kind of results will the farmer have?
a very poor performance of the Bt corn in controlling ECB because all members of the population would survive.
What would happen if the opaque-2 gene was mutated and could not be transcribed?
all of the above.
Assume that 'X' and 'Z' are alleles, different versions of genes that encode proteins the corn borers make in their gut. The picture shows a representative sample of the members of the current corn borer population. Corn borers that are XX and XZ have the best digestive system for eating corn plant tissues and reach adulthood more rapidly and in better health than corn borers that are ZZ. Given the description in the paragraph above when the population of corn borers is eating corn...
allele X should be more common in the gene pool next year than this year.
A cell in an organism has the genes Aa and Bb. When this cell completes mitosis the organism will have two cells that have what genes?
both AaBb
Roundup herbicide resistance is a genetically engineered trait first commercialized in soybeans and now found in corn and other crops. The Roundup resistance gene comes from a bacteria called Agrobacterium. To produce Roundup resistant (Roundup Ready) corn the scientist would
change the first three steps in the picture to involve a different bacteria and a different gene then do the last two steps the same way as with Bt corn
What is one thing genetic engineering allows breeders to do that they cannot do with traditional breeding?
combine the genetic information from one species with a different species
In a dicot seed, what part serves the function of storing biomolecules that support the developing seedling?
cotyledons
Ash trees are dioecious. An ash tree in your front yard never produces seeds. This is because....
could be both of the above.
A corn plant is flowering during a week when the highs are over 100°F. The ear that is harvested from this plant has about 100 seeds scattered around the ear rather than 600 seeds that can potentially be produced. This observation indicates that the high temps.......
damaged most of the male gametes
Cottonwood trees make seeds attached to a fluffy, floating material. The purpose of this strategy of seed production is to...
distribute the seed
Some plants make seeds inside of fruits that are an attractive food for birds or other animals. The purpose of this strategy of seed production is to...
distribute the seed
In a monocot seed, what part is most responsible for storing biomolecules that support the developing seedling?
endosperm
In a monocot seed, what part serves the function of storing biomolecules that support the developing seedling?
endosperm
Your apple developed from one flower. Your apple has 15 seeds in it. Therefore the one apple flower that developed into your apple.
had 15 ovules produce eggs that combined with pollen grains.
US and worldwide use of Roundup Ready soybeans and other crops has steadily increased. Based on this information, what has happened to selection pressure on weeds for resistance to glyphosate herbicides?
increased
What is the critical biological accomplishment that is necessary for a successful pest that will persist in nature?
it must complete its lifecycle and produce many offspring
Monoecious plants have:
male flowers and female flowers on the same plant but in different flowers.
Which factor or factors below reduced the effectiveness of the Bt on the rootworms in this population?
only b and c, the toxicity of the Bt toxin does not change
A farmer plants BT corn which kills XX and XZ European Corn Borers (ECB) in the population depicted below. They also plant a refuge on half their field that has corn that does not make Bt proteins and the surviving adults from the ECB population in both the Bt and the refuge part of the field will mate to produce the next generation. Adding a refuge compared with planting all Bt corn....
places less selection pressure on the ECB population
Penstemon seeds are small and have a hard seed coat that resists water penetration. The purpose of these features are...
protect the seed and maximize the chance the seed will germinate when conditions favor seedling growth.
Andy runs a genetic engineering company and is contacted to make a genetically engineered pomegranate that has cinnamon flavored fruit. List the steps from those shown in the picture below in the correct order. The first and last steps have been given.
steps X, Y and Z are E, I then F
Why must plant genetic engineers modify the BT gene before putting it into plant cells?
the gene is designed to be turned on in bacteria cells and the genetic engineer needs to have the gene turned on in plant cells
Assume the picture below depicts a population of European corn borer (ECB) that has XX,XZ and ZZ individuals. They are living on a corn hybrid that makes enough Bt protein so that individuals with the genotype XZ or ZZ survive but XX individuals die when feeding on this corn. As a result of this selection pressure...
the gene pool would have the X allele and the Z allele next year but a lower amount of the X allele.
The planting plan below shows the farmer will plant 20% of the field in non-BT seeds but they will plant in two 10% blocks. The impact this plan will have on selection pressure on the rootworm population compared with a refuge in the field of one 20% block would be....
the selection pressure will be the same
Buffalograss breeders are selecting for genotypes of plants that tolerate or resist chinch bugs. In order to identify buffalograss (no space) plants that are tolerant/resistant to chinch bugs, they need to make asexual clones of the same plants. The reason why they do the study on clones is...
they will be more confident in their ability to select the resistant plants because there will be almost no genetic variability among the clones
Castor beans are monoecious. You have one castor bean plant in your garden. Therefore...
this plant can produce seeds by itself.
The mode of action of an ALS herbicide is to bind to the enzyme called ALS which is used to build three of 20 amino acids all plants need to build proteins. The mode of action of glyphosate (Roundup) herbicide is to bind to the enzyme called EPSPS, which is used in a different amino acid making pathway in plants. If a Mare's Tail weed population becomes resistant to glyphosate....
we cannot assume it will also be resistant to ALS herbicides.Since the two herbicide groups have different modes of action, they kill the plant in different ways.
Farmers and gardeners can apply chemicals that are herbicides in low doses to weeds. The herbicide molecule will interact with a specific plant function but not interact with animals, thus is safe for people to work with in their weed control work. When the herbicide works well, the farmer or gardener will be inclined to use the same herbicide again to kill weeds. The potential problem with the continual use of an herbicide is that it...
works so well that it is applying a lot of selection pressure on weeds and weed populations could develop resistance to the herbicides.
Assume that corn plant #14 was the genotype Bb and produced offspring from self pollination. What are the expected phenotypes and fractions expected among the offspring from this cross?
¾ blue: ¼ yellow
