Question 1

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

Accepted Answer

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

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

Accepted Answer

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

Question 3

Double fertilization means that ________.

Accepted Answer

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 4

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

Accepted Answer

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

Question 5

Which statement concerning grafting is correct?

Accepted Answer

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 6

Double fertilization means that

Accepted Answer

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 7

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 ________.

Accepted Answer

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 8

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?

Accepted Answer

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 9

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?

Accepted Answer

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

Question 10

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?

Accepted Answer

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

Question 11

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?

Accepted Answer

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 12

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?

Accepted Answer

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 13

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

Accepted Answer

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 14

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?

Accepted Answer

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 15

"Golden Rice" ________.

Accepted Answer

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 16

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?

Accepted Answer

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 17

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

Accepted Answer

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 18

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

Accepted Answer

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

Question 19

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

Accepted Answer

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 20

"Bt maize"

Accepted Answer

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.

Exam 38: Angiosperm Reproduction and Biotechnology