Deck 38: Angiosperm Reproduction and Biotechnology

Question 1

If an ovary contains 50 ovules, what is the minimum number of pollen grains that must land to form 50 mature seeds?

A) 25
B) 50
C) 100
D) 500

Answer 1

B

Question 2

In a typical angiosperm, what is the sequence of structures encountered by the tip of a growing pollen tube on its way to the egg?
1) micropyle
2) style
3) ovary
4) stigma

A) 4 → 2 → 3 → 1
B) 4 → 3 → 2 → 1
C) 1 → 3 → 4 → 2
D) 3 → 2 → 4 → 1

Answer 2

A

Question 3

Which of the following pollinating agents is correctly matched with the type of plant it helps pollinate?

A) Water-terrestrial plants
B) Animals-aquatic plants
C) Wind-grasses
D) Sand-desert plants

Answer 3

C

Question 4

During the alternation of generations in plants, ________.

A) meiosis produces gametes
B) mitosis produces gametes
C) fertilization produces spores
D) fertilization produces gametes

Question 5

Arrange the following structures from largest to smallest, assuming that they belong to two generations of the same angiosperm.
1)ovary
2)ovule
3)egg
4)carpel
5)embryo sac

A) 4, 2, 1, 5, 3
B) 5, 4, 3, 1, 2
C) 5, 1, 4, 2, 3
D) 4, 1, 2, 5, 3

Question 6

Which of the following is correctly paired with its life cycle generation?

A) anther-sporophyte
B) pollen-sporophyte
C) embryo sac-gametophyte
D) stamen-gametophyte

Question 7

Which of the following is the correct order of floral organs from the outside to the inside of a complete flower?

A) petals → sepals → stamens → carpels
B) sepals → stamens → petals → carpels
C) spores → gametes → zygote → embryo
D) sepals → petals → stamens → carpels

Question 8

A typical angiosperm embryo sac (female gametophyte) has ________ cells.

A) 2
B) 1
C) 8
D) 4

Question 9

Which of these is a major trend in land plant evolution?

A) the trend toward smaller size
B) the trend toward a gametophyte-dominated life cycle
C) the trend toward a sporophyte-dominated life cycle
D) the trend toward larger gametophytes

Question 10

Retaining the zygote on the living gametophyte of land plants ________.

A) protects the zygote from herbivores
B) evolved concurrently with pollen
C) helps in dispersal of the zygote
D) allows it to be nourished by the parent plant

Question 11

Which of the following statements regarding flowering plants is correct?

A) The gametophyte is the dominant generation.
B) Female gametophytes develop from megaspores within the anthers.
C) Pollination is the delivery of pollen to the stigma of a carpel.
D) The food-storing endosperm is derived from the cell that contains one polar nucleus and two sperm nuclei.

Question 12

Sperm cells are formed in plants by ________.

A) meiosis in pollen grains
B) meiosis in anthers
C) mitosis in male gametophyte
D) mitosis in the micropyle

Question 13

The generative cell of male angiosperm gametophytes is haploid. This cell divides to produce two haploid sperm cells. What type of cell division does the generative cell undergo to produce these sperm cells?

A) mitosis
B) meiosis
C) mitosis without subsequent cytokinesis
D) meiosis without subsequent cytokinesis

Question 14

Double fertilization means that ________.

A) flowers must be pollinated twice to yield fruits and seeds
B) one sperm is needed to fertilize the egg, and a second sperm is needed to fertilize the polar nuclei
C) the egg of the embryo sac is diploid
D) every sperm has two nuclei

Question 15

Suppose that 100 pollen grains land on a stigma, and 50 mature seeds are formed in the fruit. What does this indicate about the pollination process and success?

A) 50% success: 100 pollen grains grew to 50 ovules, and double fertilization occurred.
B) 50% success: Evidently, only 50 sperm pollinated 50 anthers.
C) 50% success: 50 sperm fertilized 50 eggs, and 50 sperm fused with 50 polar nuclei.
D) 50% success: 50 sperm fertilized 50 eggs, and 50 sperm fused with 100 polar nuclei.

Question 16

In a typical dicot ovule, a surviving megaspore divided by ________ consecutive mitotic divisions without cytokinesis results in ________ nuclei.

A) 2; 6
B) 3; 8
C) 3; 12
D) 4; 16
E) 1; 1

Question 17

Double fertilization in angiosperm embryo sac produces endosperm, a food-storing tissue of the seed. The genetic makeup of endosperm is ________.

A) 2n
B) 3n
C) 4n
D) n

Question 18

A researcher has developed two stains for use with seed plants. One stains sporophyte tissue blue; the other stains gametophyte tissue red. If the researcher exposes pollen grains to both stains, and then rinses away the excess stain, what should occur?

A) The pollen grains will be pure red.
B) The pollen grains will be pure blue.
C) The pollen grains will have red interiors and blue exteriors.
D) The pollen grains will have blue interiors and red exteriors.

Question 19

A summer occupation in the Corn Belt states is de-tasseling the corn: removing unwanted male flowers so that female flowers on the same plant are pollinated by the desired pollen for the hybrid corn. What does this tell you about corn? The flowers are ________.

A) perfect and the plant is dioecious
B) perfect and the plant is monoecious
C) imperfect and the plant is dioecious
D) imperfect and the plant is monoecious

Question 20

In which of the following pairs are the two terms equivalent?

A) ovule - egg
B) embryo sac - female gametophyte
C) seed - zygote
D) microspore - pollen grain

Question 21

What adaptations should one expect of the seed coats of angiosperm species whose seeds are dispersed by frugivorous (fruit-eating) animals, as opposed to angiosperm species whose seeds are dispersed by other means?
1)The exterior of the seed coat should have barbs or hooks.
2) The seed coat should contain secondary compounds that irritate the lining of the animal's mouth.
3)The seed coat should be able to withstand low pHs.
4)The seed coat, upon its complete digestion, should provide vitamins or nutrients to animals.
5)The seed coat should be resistant to the animals' digestive enzymes.

A) 4 only
B) 1 and 2
C) 3 and 5
D) 3, 4, and 5

Question 22

While looking at a flower in your garden, you notice that it has carpels with very long styles, and stamens with very short filaments. This plant is most likely to reproduce by ________.

A) cross-pollination
B) selfing
C) asexual reproduction
D) vegetative reproduction

Question 23

Pineapple is a ________ fruit.

A) simple
B) multiple
C) aggregate
D) accessory

Question 24

Which of the following could be considered an evolutionary advantage of asexual reproduction in plants?

A) increased success of progeny in a stable environment
B) increased agricultural productivity in a rapidly changing environment
C) maintenance and expansion of a large genome
D) increased ability to adapt to a change in the environment

Question 25

Plants produce more seeds when they reproduce asexually than sexually. Yet most plants reproduce sexually in nature. What is the probable explanation for the prevalence of sexual reproduction? Sexual reproduction ________.

A) is more energy efficient than asexual reproduction
B) ensures genetic continuity from parents to offspring
C) mixes up alleles, contributing to variation in a species
D) is not dependent on other agents of pollination

Question 26

Which of the following is a potential advantage of introducing apomixis into hybrid crop species?

A) Cultivars would be better able to cope with a rapidly changing environment.
B) They would have a larger potential genome than inbred crops.
C) All of the desirable traits of the cultivar would be passed on to offspring.
D) They would benefit from positive mutations in their DNA.

Question 27

Use the following information to answer the question.
The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8-25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can now enter. The uneaten seeds may subsequently germinate.
Animals that consume Brazil nuts derive nutrition mostly from tissue whose nuclei have how many chromosomes?

A) 17
B) 34
C) 51
D) 68

Question 28

In a multicellular organism, any cell that can divide and generate a/an ________ of the original organism is called to be totipotent.

A) organ
B) clone
C) tissue
D) cell

Question 29

The egg of a plant has a haploid chromosome number of 12 (n = 12). What is true about the number of chromosomes in the cells of other tissues of this plant?

A) The sperm has 6 chromosomes.
B) The leaves and stems have 12 chromosomes.
C) The zygote has 12 chromosomes.
D) The endosperm has 36 chromosomes.

Question 30

Which of these events occurs first in seed germination?

A) Cell division occurs in the embryo and growth starts.
B) Mitochondria multiply and provide energy for growth processes.
C) Water is taken up.
D) Oxygen is produced and proteins are synthesized.

Question 31

Which of the following types of plants are incapable of self-pollination?

A) dioecious
B) monoecious
C) wind-pollinated
D) insect-pollinated

Question 32

Before plowing a field, a farmer thought the bare field looked weed-free. Three days after plowing and turning over the soil, he was amazed to see thousands of tiny seedlings. What is the most likely reason for the mass germination of seeds?

A) large seeds that needed soil disturbance to germinate
B) small seeds that need light to germinate
C) small seeds that were scarified by exposure to plow
D) large seeds that needed exposure to higher levels of oxygen to germinate

Question 33

Use the following information to answer the question.
The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8-25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can now enter. The uneaten seeds may subsequently germinate.
Orchid bees are to Brazil nut trees as ________ are to pine trees.

A) breezes
B) rain droplets
C) seed-eating birds
D) squirrels

Question 34

The vast number and variety of flower species is probably related to various kinds of ________.

A) seed dispersal agents
B) pollinators
C) herbivores
D) climatic conditions

Question 35

Cottonwood, aspen, and willow trees have beige flowers, with no petals, that appear before the tree's leaves are out in the spring; and they are dioecious. What does this indicate about these trees?

A) Their insect pollinators are specialists.
B) Early emerging insects are probably the pollinators.
C) Their pollen is dispersed by wind.
D) The trees are self-pollinating.

Question 36

Which of the following flower parts develops into a seed?

A) ovule
B) ovary
C) stamen
D) carpel

Question 37

Among plants known as legumes (beans, peas, alfalfa, clover, for example), the seeds are contained in a fruit that is itself called a legume, better known as a pod. Upon opening such pods, it is commonly observed that some ovules have become mature seeds, whereas other ovules have not. Thus, which of the following statements is (are) true?
1)The flowers that gave rise to such pods were not pollinated.
2)Pollen tubes did not enter all of the ovules in such pods.
3)There was apparently not enough endosperm to distribute to all of the ovules in such pods.
4)The ovules that failed to develop into seeds were derived from sterile floral parts.
5)Fruit can develop, even if all ovules within have not been fertilized.

A) 1 only
B) 1 and 5
C) 2 and 5
D) 3 and 5

Question 38

Use the following information to answer the question.
The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8-25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can now enter. The uneaten seeds may subsequently germinate.
The same bees that pollinate the flowers of the Brazil nut trees also pollinate orchids, which are epiphytes (in other words, plants that grow on other plants); however, orchids cannot grow on Brazil nut trees. These observations explain ________.

A) the coevolution of Brazil nut trees and orchids
B) why Brazil nut trees do not set fruit in monoculture plantations
C) why male orchid bees do not pollinate Brazil nut tree flowers
D) why male orchid bees are smaller than female orchid bees

Question 39

Which of the following flower parts develops into the pulp of a fleshy fruit?

A) stigma
B) style
C) ovule
D) ovary

Question 40

Which of the following is a true statement about asexual reproduction in plants?

A) Clones of plants do not occur naturally.
B) Cloning, although achieved in animals, has not been demonstrated in plants.
C) Making cuttings of ornamental plants is a form of fragmentation.
D) Reproduction of plants by cloning may be either sexual or asexual.

Question 41

Over human history, which process has been most important in improving the features of plants that have long been used by humans as staple foods?

A) genetic engineering
B) artificial selection
C) sexual selection
D) pesticide and herbicide application

Question 42

Plant biotechnology is an effective tool for ________.

A) reducing world hunger
B) increasing the import of oil
C) decreasing genetic diversity
D) increasing the incompatibility of fertilization

Question 43

Many flowering plants coevolve with specific pollinators. The Madagascar orchid has a 12-inch floral tube and is a reliable nectar source for the hawkmoth, which has a correspondingly long proboscis (tongue). Which statement most accurately describes how coevolution might have occurred for the hawkmoth and Madagascar orchid?

A) The hawkmoths that expended the most effort to reach the nectar would be the most fit, and pass the longer tongue phenotype to their offspring.
B) Natural selection would favor orchids with nectar tubes just long enough to for an insect with pollen to make contact. Hawkmoths whose tongue could reach the deep tubes would be more fit.
C) Hawkmoths whose tongue was just long enough to obtain nectar, but not able to pick up pollen would become the most fit in the population.
D) It is most likely that mutations that resulted in both the length of the orchid floral tube and the length of the hawkmoth tongue occurred abruptly and simultaneously.

Question 44

Some dioecious species have the XY genotype for male and XX for female. After double fertilization, what would be the genotypes of the embryos and endosperm nuclei?

A) embryo XY/endosperm XXX or embryo XX/endosperm XXY
B) embryo XX/endosperm XX or embryo XY/endosperm XY
C) embryo XX/endosperm XXX or embryo XY/endosperm XYY
D) embryo XX/endosperm XXX or embryo XY/endosperm XXY

Question 45

Which of these activities is part of the development of crop plants from wild relatives?
I)people planting seeds of the plants with the characteristic wanted
II)people making observations of desired plant characteristics
III)people eating products from only the plants with desired characteristics
IV)people developing several varieties of crops from a wild relative

A) I and II
B) I and IV
C) I, III, and IV
D) I, II, and IV

Question 46

Regardless of where in the world a vineyard is located, for the winery to produce a Burgundy, it must use varietal grapes that originated in Burgundy, France. The most effective way for a new California grower to plant a vineyard to produce Burgundy is to ________.

A) plant seeds obtained from French varietal Burgundy grapes
B) transplant varietal Burgundy plants from France
C) acquire a tissue culture of varietal Burgundy grapes from France
D) graft varietal Burgundy grape scions onto native (Californian) root stocks

Question 47

"Bt maize"

A) is resistant to various herbicides, making it practical to weed rice fields with those herbicides.
B) contains transgenes that increase vitamin A content.
C) includes bacterial genes that produce a toxin that reduces damage from insect pests.
D) is a "boron (B)-tolerant" transgenic variety of maize.

Question 48

Fruit ripening represents an example of positive feedback. Which one of the following statements accurately justifies why the process of fruit ripening involves positive feedback?

A) Once seeds have reached maturity, chemical signals increase enzymatic activity in fruit to convert sugars into starches, thicken pulp, and maintain color in the fruit.
B) Once seeds have reached maturity, chemical signals block enzymatic steps that normally convert sugars into starches, and sugars accumulate from photosynthetic activity within the fruit.
C) Chemical signals initiate a process that triggers enzymatic activity, which involves converting starches into sugars, softening of pulp, and color change of fruit.
D) Chemical signals shut down enzymatic activity within the fruit, which results in breakdown of starches into sugars, softening of pulp, and color change of fruit.

Question 49

Which of the following would be the most problematic for the natural environment in the development of genetically engineered crops?

A) the introduction of male sterility into crops
B) the creation of transgenic crops with apomictic seeds
C) the creation of crops with flowers that develop normally, but fail to open
D) the creation of transgenic crops that hybridize more easily

Question 50

Double fertilization means that

A) flowers must be pollinated twice to yield fruits and seeds.
B) every egg must receive two sperm to produce an embryo.
C) one sperm is needed to fertilize the egg, and a second sperm is needed to fertilize the polar nuclei.
D) every sperm has two nuclei.

Question 51

In order for an ovule (egg cell) in a flower to be fertilized and form a viable seed, pollination must occur. In this process, a sperm cell is delivered to the ovule when the pollen grain lands on the stigma and grows a tube, which enters the ovary and discharges the sperm cell to form a diploid zygote when it fuses with the egg cell. Although it only takes one pollen grain to successfully deliver sperm to the egg, numerous pollen grains are generally transferred to the stigma during insect pollination of flowering plants. Which phenotypic traits of pollen would you predict to be selected upon to promote survival and fitness within an insect-pollinated flowering plant?

A) high pollen tube growth rate and ability to detect chemicals from cells surrounding the egg
B) ability to produce the most cells during mitotic growth of the pollen tube
C) elaborate and striking UV "nectary guides" on the petals to guide an insect to the stigma
D) larger pollen in order to carry the tube that is necessary for delivery of the sperm cells

Question 52

Which of the following is a scientific concern related to creating genetically modified crops?

A) Herbicide resistance may spread to weedy species.
B) Genetically modified crops cannot survive without the addition of great amounts of fertilizer to the soil.
C) The monetary costs of growing genetically modified plants are significantly greater than traditional breeding techniques.
D) Genetically modified plants are less stable and may revert back to parental genotypes.

Question 53

Which statement concerning grafting is correct?

A) Stocks and scions refer to twigs of different species.
B) Stocks and scions must come from unrelated species.
C) Stocks provide root systems for grafting.
D) Grafting creates new species.

Question 54

A fruit is

A) a mature ovary.
B) a mature ovule.
C) a seed plus its integuments.
D) an enlarged embryo sac.

Question 55

Which of the following is an effective method to produce plants exhibiting hybrid vigor?

A) self-pollination
B) cloning
C) tissue culture
D) genetic engineering

Question 56

"Golden Rice" ________.

A) is resistant to various herbicides, making it practical to weed rice fields with those herbicides
B) includes bacterial genes that produce a toxin that reduces damage from insect pests
C) produces larger, golden grains that increase crop yields
D) contains daffodil genes that increase vitamin A content

Question 57

The most immediate potential benefits of introducing genetically modified crops include ________.
I)creating crops that can grow on land previously unsuitable for agriculture
II)creating crops with better potential for biofuel production
III)creating crops with better nutritional attributes
IV)increasing crop yield
V)decreasing the mutation rate of certain genes

A) only II, III, and IV
B) only I, II, III, and IV
C) only III, IV, and V
D) I, II, III, IV, and V

Question 58

Pollen from a plant with the S₁S₂ genotype is recognized and allowed to germinate on the stigma of the same plant with the S₁S₂ genotype. According to this, the plant is ________.

A) self-compatible and can self-pollinate
B) self-compatible and must cross-pollinate
C) self-incompatible and can self-pollinate
D) self-incompatible and must cross-pollinate

Question 59

A small flower with green petals is most likely

A) bee-pollinated.
B) bird-pollinated.
C) bat-pollinated.
D) wind-pollinated.

Question 60

The black dots that cover strawberries are actually fruits formed from the separate carpels of a single flower. The fleshy and tasty portion of a strawberry derives from the receptacle of a flower with many separate carpels. Therefore, a strawberry is

A) a simple fruit with many seeds.
B) both a multiple fruit and an accessory fruit.
C) both a simple fruit and an aggregate fruit.
D) both an aggregate fruit and an accessory fruit.