Question 1

Which of the following is true of stomata?

Accepted Answer

Stomata are openings on the leaves and stems of plants that allow for gas exchange (CO2 in, O2 out) and water vapor to escape. They open during the day to facilitate photosynthesis but close at night to prevent water loss.

Question 2

Use the following information when answering the corresponding question(s).
Scarlet gilia (Ipomopsis aggregata)usually has red flowers in an inflorescence of up to 250 flowers.In certain populations in the Arizona mountains,however,the flowers range from red to pink to white.In early summer,most of the flowers were red.Six to eight weeks later,the same individual plants were still present;the flowers ranged from pink to white,and few red flowers were present.The major pollinators early in the season were two species of hummingbirds active during the day;they emigrated to lower elevations,and the major pollinator later in the season was a hawk moth (a type of moth).The hawk moth was most active at sunset and later,and it preferred light pink to white flowers after dark.When hummingbirds were present,more red flowers than white flowers produced fruit.When only hawk moths were present,more white flowers produced fruit (K.N.Paige and T.G.Whitham.1985.Individual and population shifts in flower color by scarlet gilia: A mechanism for pollinator tracking.Science 227:315-17).
-Refer to the paragraph on scarlet gilia.Some plants changed their flowers to lighter colors,and some retained the same darker color all season.Which plants do you expect produced more fruit?

Accepted Answer

The hawk moth, the major pollinator later in the season, preferred light pink to white flowers after dark. When only hawk moths were present, more white flowers produced fruit. This suggests that the plants that changed their flowers to lighter colors (pink to white) would have produced more fruit.

Question 3

What two major novelties allowed for the first colonization of terrestrial habitats by plants?

Accepted Answer

The cuticle and pores were crucial adaptations that allowed early plants to colonize land by preventing water loss and allowing gas exchange, respectively.

Question 4

Spores and seeds have basically the same function-dispersal-but are vastly different because _____.

Accepted Answer

Spores are typically unicellular, whereas seeds are multicellular and contain an embryo along with stored nutrition.

Question 5

The retaining of the zygote on the living gametophyte of land plants _____.

Accepted Answer

The retaining of the zygote on the living gametophyte of land plants allows it to be nourished by the parent plant, which is necessary for the growth and development of the embryo. This is important for almost all land plants, including non-seed plants such as mosses and ferns.

Question 6

Use the following information when answering the corresponding question(s).
Scarlet gilia (Ipomopsis aggregata)usually has red flowers in an inflorescence of up to 250 flowers.In certain populations in the Arizona mountains,however,the flowers range from red to pink to white.In early summer,most of the flowers were red.Six to eight weeks later,the same individual plants were still present;the flowers ranged from pink to white,and few red flowers were present.The major pollinators early in the season were two species of hummingbirds active during the day;they emigrated to lower elevations,and the major pollinator later in the season was a hawk moth (a type of moth).The hawk moth was most active at sunset and later,and it preferred light pink to white flowers after dark.When hummingbirds were present,more red flowers than white flowers produced fruit.When only hawk moths were present,more white flowers produced fruit (K.N.Paige and T.G.Whitham.1985.Individual and population shifts in flower color by scarlet gilia: A mechanism for pollinator tracking.Science 227:315-17).
-Refer to the paragraph on scarlet gilia.Late in the season,when only hawk moths were present,researchers painted the red flowers white.What would you expect?

Accepted Answer

According to the information given, hawk moths preferred light pink to white flowers after dark. Therefore, painting the red flowers white may increase the chances of the hawk moths pollinating them and result in more fruit production from the red flowers that were painted white compared to the unpainted red flowers.

Question 7

Which of these are structures in a gametophyte generation?

Accepted Answer

Spores, egg, sperm, pollen, and archegonium are all structures in the gametophyte generation. Leaves, stems, roots, flowers, and cones are structures in the sporophyte generation. Antheridium is a structure in the male gametophyte, but not the gametophyte generation as a whole. Embryo, seed, zygote, and seedling are structures in the sporophyte generation.

Question 8

Which of these are spore-producing structures?

Accepted Answer

The sporophyte of a moss is a capsule that produces spores. The other structures mentioned in the options (antheridia, archegonia, and gametophytes) produce gametes, not spores.

Question 9

What is true about the genus Sphagnum?

Accepted Answer

The genus Sphagnum, commonly known as peat moss, is an important carbon sink. It accumulates dead plant material in wetlands, bogs, and marshes, where it can remain for thousands of years. This process reduces atmospheric CO₂ and helps to mitigate climate change.

Question 10

Liverworts,hornworts,and mosses are grouped together as the Bryophytes.Besides not having vascular tissue,what do they all have in common?

Accepted Answer

Liverworts, hornworts, and mosses all require water for reproduction because they produce swimming sperm that require water to swim to the egg.

Question 11

Which of these processes does not result in the formation of a different generation in a plant's sexual life cycle?

Accepted Answer

Mitosis is a process of cell division that produces identical copies of the original cell. It does not lead to the formation of a new generation as it does not involve the fusion of gametes or the formation of spores. Pollination, meiosis, and fertilization, on the other hand, all involve the production of genetically diverse offspring and thus result in the formation of a new generation in a plant's sexual life cycle.

Question 12

As you stroll through a moist forest,you are most likely to see a _____.

Accepted Answer

The answer of As you stroll through a moist forest,you...

Question 13

How are the bryophytes and seedless vascular plants alike?

Accepted Answer

Both bryophytes and seedless vascular plants require water for sperm to swim from antheridia to archegonia for fertilization.

Question 14

The herbicide 2,4-D affects the metabolism of dicots and kills most of them.What is a common feature of plants that are susceptible to 2,4-D?

Accepted Answer

2,4-D is a selective herbicide that targets broadleaf weeds, which are generally dicotyledonous plants. A common feature of dicots is branching leaf veins, unlike monocots which typically have parallel leaf veins.

Question 15

How could you determine if a plant is heterosporous?

Accepted Answer

Heterosporous plants produce two types of spores: microspores (which develop into male gametophytes, often producing pollen) and megaspores (which develop into female gametophytes).

Question 16

Because they are morphologically simple,Psilotophyta have traditionally been thought to be a basal group in the radiation of land plants.Molecular phylogenies have challenged this hypothesis and support the alternative hypothesis that _____.

Accepted Answer

Molecular phylogenies suggest that Psilotophyta have lost complex structures, indicating they are not as basal as once thought.

Question 17

Which of the following is a correct element of alternation of generations?

Accepted Answer

Alternation of generations is a life cycle found in certain organisms, where two distinct multicellular phases alternate with each other, a haploid gametophyte and a diploid sporophyte. The sporophyte phase produces spores through meiosis, which then develop into the gametophyte phase through mitosis. Therefore, the correct element of alternation of generations is that the sporophyte is diploid and produces spores.

Question 18

Which of the following innovations is not associated with angiosperm diversification?

Accepted Answer

Leaves are not specifically associated with angiosperm diversification. While leaves are an important component of photosynthesis and most angiosperms have leaves, they existed in other plant groups before the diversification of angiosperms. The other three innovations listed (vessel elements, flowers, and fruits) are unique to angiosperms and are thought to have played a role in their diversification and success.

Question 19

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

Accepted Answer

The huge variety of flowers is related to the need for different pollinators. The unique shapes, colors, fragrances, and nectar of various flowers attract different types of pollinators, such as bees, butterflies, birds, and even bats. Therefore, different species of flowers have evolved over time to match specific pollinators and ensure successful reproduction. While seed dispersal agents, herbivores, and climatic conditions play a role in the evolution of flower species, they are not as directly related to the diversity of flowers as pollinators.

Question 20

Use the following information when answering the corresponding question(s).
Scarlet gilia (Ipomopsis aggregata)usually has red flowers in an inflorescence of up to 250 flowers.In certain populations in the Arizona mountains,however,the flowers range from red to pink to white.In early summer,most of the flowers were red.Six to eight weeks later,the same individual plants were still present;the flowers ranged from pink to white,and few red flowers were present.The major pollinators early in the season were two species of hummingbirds active during the day;they emigrated to lower elevations,and the major pollinator later in the season was a hawk moth (a type of moth).The hawk moth was most active at sunset and later,and it preferred light pink to white flowers after dark.When hummingbirds were present,more red flowers than white flowers produced fruit.When only hawk moths were present,more white flowers produced fruit (K.N.Paige and T.G.Whitham.1985.Individual and population shifts in flower color by scarlet gilia: A mechanism for pollinator tracking.Science 227:315-17).
-Refer to the paragraph on scarlet gilia.What is the significance of measuring fruit production?

Accepted Answer

Measuring fruit production is significant because it is a measure of pollination success. The number of fruits produced by a plant indicates how many flowers were successfully pollinated and fertilized, which is an important measure of reproductive success for a plant.

Quiz 30: Green Plants