Biol 1620 Test 2

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sporopollenin

A complex mixture of polymers that is remarkably resistant to environmental stresses such as ultraviolet radiation and desiccation. In plants, found in the walls of pollen and spores. [ex: Chara's zygotes secrete tough wall]

What is the advantage of a fungal body being composed of numerous thin hyphae instead of one or two very thick hyphae?

A greater surface area is available for absorption of nutrients.

epiphtyes

A plant that grows on branches or trunks of trees, without contact with the soil.

spores

A reproductive cell capable of growing into a new individual without fusion with another cell.

The ancestors of seed plants evolved the ability to produce additional or "secondary" xylem and phloem through the formation of a vascular cambium. This layer of actively dividing and differentiating cells surrounds stems and allows them to increase in diameter.

A second layer of dividing cells, the cork cambium, maintains an intact layer of protective outer bark. Vascular and cork cambia provide the support and water transport capacity needed for plants to grow tall and to support increasing numbers of leaves.

Four major events that transformed how plants grow and reproduce. 4. Evolution of flowering plants, the angiosperms.

Flowers are the signature feature but others are: -Carpels, double fertilization leading to endosperm, xylem vessels, fruits. -Most diverse group of plants

A scientist takes a cross section from a conifer. She notices a small nucleus contained within a lignified cell wall. This cell is most likely:

an immature tracheid cell.

Which of these choices is thought to have been a major contributor to the diversification or ecological dominance of angiosperms during the Cretaceous Period?

animal pollination

Are there any habitats where a bryophyte might be more productive than a vascular plant?

anywhere without soil like on top of rocks

Fungi are most closely related to:

arthropods, which are organisms that also produce chitin.

Which of these structures form lateral branches in gymnosperms and angiosperms?

axillary buds

Which of the statements helps explain why there are abundant air spaces between mesophyll cells in leaves?

because CO2 diffusion is faster in air than in water

in vascular plants the sporophyte is the dominant generation, both because the sporophyte is physically larger than the gametophyte and

because its photosynthetic production is much higher.

in gymnosperms, resources for the embryo are committed

before fertilization.

Flower organization:

concentric whorls of floral organs. The outer whorls consist of sepals and petals, while the inner whorls are made up of pollen-producing stamens and ovule-producing carpels. Ovules are produced on inner surface of carpel. --only pollen from the same species will germinate and grow successfully.

Ferns release swimming sperm, so they are able to reproduce only when

conditions are wet. That is true of the other spore-dispersing plants (lycophytes, horsetails, and bryophytes) as well.

Which group of plants contains the tallest and oldest trees on Earth?

conifers

If you see a vascular plant that is growing low to the ground with branching stems covered by small leaves and that produced leaves with a single vein, you are most likely observing a(n):

lycophyte.

In many groups of fungi, karyogamy and plasmogamy are separated in time and space. One potential advantage of this arrangement is that:

mating and spore production can occur in different environments.

While looking at a plant, you notice that the major veins in its leaves are parallel to the middle vein, its vascular bundles are distributed throughout the stem, and only one leaf attaches to any of the nodes. You are looking at a(n):

monocot

Which group of angiosperms contributes most to the global food supply for human societies?

monocots

Angiosperms that have only one embryonic seed leaf are called:

monocots.

land plants (embryophyta) are

monophyletic

Which groups both have short-lived sporophytes?

mosses and liverworts

The gametophyte is photosynthetically self-sufficient, but the sporophytes:

must obtain water and nutrients needed for their growth from the gametophyte.

Within the fungal body, nutrients are transported from the _____ to the _____ by the process of _____.

mycelium; fruiting body; bulk flow

All of the traits are shared between animals and at least some fungi, except:

none of the answers are correct

In seed plants, the embryo develops inside the seed, which allows for:

nutrient reserves for the developing diploid embryo.

Floral organs:

occur in whorls.

Asexual reproduction in plants results in:

offspring that are genetically identical to the parent.

early land plants evolved a life cycle with two distinct multicellular generations:

one generation released sperm into a moist environment, and the following generation dispersed offspring through the air. A pattern of alternating generations, one haploid and one diploid, still exists in all plants today.

green algae are

paraphyletic because the descendants of their last common ancestor also include the land plants.

In seed plants, the gametophyte generation is

physically and physiologically dependent on the sporophyte.

Which of the answer choices correctly lists the arrangement of tissues and vascular bundles in the stem of a seed plant, from the center of the stem to the periphery?

pith, xylem, phloem, cortex

Which of the answer choices represents the correct order of events in fungal sexual reproduction, starting from when hyphae of two different mating types grow together?

plasmogamy → heterokaryotic stage → karyogamy → zygote → meiosis → spore production and dispersal → haploid mycelium

The movement of auxin from the apical to basal sides of immature leaf cells and toward the xylem and phloem of the stem is an example of _____ transport.

polar

Angiosperm mating systems: self-compatible species

pollen and eggs produced by flowers on the same plant can unite and produce viable offspring [ex: weed,crops]

The transport of pollen to the ovule is called:

pollination

Roots are thought to load strigolactones into the xylem to _____ when soils are _____.

suppress the production of branches and thus new leaf area; dry

Which of the choices was not a key event in the evolution of vascular plant leaves?

the development of apical meristem identity genes

In plants, the zygote does not undergo meiosis, and it does not disperse. Instead, the zygote is retained within

the female reproductive organ. There, it divides repeatedly by mitosis to produce a new multicellular plant—this one made of diploid cells

Transpiration is best defined as:

the loss of water vapor from leaves.

A pine seed contains tissues from three generations:

the seed coat formed from diploid sporophyte layers, the haploid female gametophyte, and the diploid embryo, which will grow into the next sporophyte generation.

In seed plants, the outermost protective tissues of the ovule are derived from:

the sporophyte.

As seeds mature, most lose water. -embryo ceases to grow. Some seeds exhibit dormancy:

they can delay germination even when conditions for growth, notably temperature and moisture, are favorable. Dormancy prevents seeds from germinating at the wrong time (too warm to survive). It also prevents seeds from germinating all at once, thereby spreading the risk of making the transition from embryo to seedling over a larger time span and range of conditions.

The multicellular sporophyte of bryophytes turns a single fertilization event into ____ new haploid individual(s), whereas fertilization in Chara and Coleochaete leads to _____ new haploid individual(s).

thousands of; four

Why do plants need an endodermis in their roots?

to provide selectivity of ions entering the xylem

Plants require the most water _____, but water is also critical _____.

to replace the water vapor lost to transpiration; as an input to photosynthesis reactions

Ascomycete yeasts evolved from multicellular ancestors.

true

New cork cambia form within the secondary phloem.

true

One of the advantages that seeds have over spores is that they contain nutritional resources, originating from photosynthesis by the maternal sporophyte, that aid in establishment.

true

Secondary xylem is produced by __________, and contributes to the ___________ of some plants.

vascular cambium; woody stem

Which of the factors causes stomata to close?

water loss

Xylem transports _____, whereas phloem transports _____.

water; sugars

Under what circumstances can leaves be sinks for carbohydrates delivered by phloem?

when they are very young

Gnetophytes are more closely related to angiosperms than to other gymnosperms.

False

Vascular plants store most carbohydrate reserves as:

starch.

Which letter on the phylogenetic tree indicates the ancestor of all land plants?

A

Which of the features are characteristics of self-compatible plants?

They have few deleterious recessive alleles.

Which of the statements about horsetails is true?

They produce small leaves arranged in whorls.

Explain how features found in angiosperms may have allowed the evolution of herbaceous plants, including annual plants.

Efficient xylem allows the production of inexpensive stems.

How do endophytes differ from endomycorrhizal fungi?

Endophytes live within leaves, whereas endomycorrhizal fungi live within roots.

4 major events that transformed how plants grow and reproduce.

1. Alternation of generations 2. Evolution of xylem & phloem in sporophyte generation. 3. Evolution of seeds and pollen 4. Evolution of flowering plants, the angiosperms.

Vascular plants have two groups: -In both groups, the sporophyte dominates in physical size. -both the sporophyte and the gametophyte are free-living -gametophyte capable of photosynthesis.

--Lycophytes, as well as ferns and horsetails, disperse by spores and rely on swimming sperm for fertilization, just like bryophytes. --Gymnosperms and angiosperms are seed plants: they disperse seeds and rely on the aerial transport of pollen for fertilization.

What methods do fungi employ to disperse their spores?

--They can instruct plants to form "fake flowers," which attract pollinators that then disperse spores. --They can produce pheromones similar to those of boars, which attract sows that disperse the spores. --They can form fruiting bodies, which expel spores above "stagnant" air. --They can highjack ants, creating "zombie ants" that (after death) disperse spores.

Asexual reproduction mechanisms: apomixis & vegetative repro.

--an embryo can form directly from a diploid sporophyte cell. --most don't produce seeds but rather a new plant grows out of part of the parent plant. Offspring dispersed by rain landing in shallow cups that have tiny tissue discs inside. --Grow to a new location.

-Bryophytes (unbranched sporophyte extends several centimeters above the gametophyte) -Hornworts (sporophyte can live nearly as long as the gametophyte because it can produce new cells at its base, similar to the way grass blades elongate)

-In mosses and liverworts, a capsule-like sporangium forms at the tip; spores are produced in this structure. (sporophyte is short-lived). After the spores mature, the sporophyte dries out and the sporangia open. Drying prevents spores from sticking together, thereby increasing the chances that a gust of wind will carry off a spore. In hornworts, the spores form at the top of the sporophyte, albeit within the stalk itself. The spores are released as the sporophyte stalk dries from the top down and splits open.

advantages of double fertilization

-Pines/Gymnosperms: female gametophyte offers food for embryo. -Angiosperms: endosperm develops only when fertiliz. occurs. Embryo draws resources from endosperm to help establish it. The growing embryo consumes all the endosperm before the seed leaves the parent plant.

Four major events that transformed how plants grow and reproduce. 3. Evolution of seeds and pollen

-Pollen could deliver sperm to female repro of another plant by air. (fertilization can occur w/o releasing swimming sperm into environment) - New dispersal unit: multicell. seeds packed w/ stored resources and surrounded by protective layers. -seeds increase prob. of the next sporophyte generation becoming a free living plant.

Bryophytes exhibit several cases of convergent evolution with the vascular plants.

-cells specialized for the internal transport of water and carbohydrates in some of the largest mosses and leafy liverworts -some mosses depend on insects to transport their spores -Stomata are present on the sporophytes of hornworts and some mosses, where a waxy cuticle also develops. Stomata are present on the sporophytes of hornworts and some mosses, particularly in places where a waxy cuticle also develops. Spores easily released through air by dried out stomata.

Bryophytes (Liverworts, mosses, and hornworts)

-depend on surface moisture for hydration -life cycle dominated by photosynthetic gametophyte (free living cell). -united by absence of key features of vascular plants (xylem & phloem) -mosses are most common -small stature (<5 cm) -Release swimming sperm through water

Monocots have one embryonic seed leaf, or cotyledon, whereas all other angiosperms have two. - monocot flowers typically produce organs in multiples of three, whereas eudicot flowers typically produce organs in multiples of four or five. Another difference is that in monocot leaves, the major veins are typically parallel and the base of the leaf surrounds the stem, forming a continuous sheath.

-monocots do not form a vascular cambium. In the stems of most monocots, the vascular bundles are scattered throughout the cross section, instead of being arrange ring like The scattered arrangement of vascular bundles is thought to preclude the formation of a continuous layer of vascular cambium. As a result, monocots do not exhibit secondary growth.

Angiosperm seed plants Similar to pine trees but different bcuz:

-pollen and ovules are produced in a single structure, the flower, rather than in separate cones.

Peat bogs have low rates of organic decomposition due to the wet and acidic conditions created by Sphagnum moss.

-specialized cells that hold onto water, much like a sponge, and they secrete protons that acidify the surrounding water. -phenols, organic compounds that slow decomposition

Bryophyte gametophytes come in two forms.

1. Some species produce only a flattened photosynthetic structure called a thallus. 2. Slender stalks with tiny leaf-like appendages. One to several cells thick and no air spaces internally. -mosses are leafy -liverworts thalloid or leafy -hornworts thalloid

The seed plant life cycle is distinguished by four major steps.

1. formation of two types of spore, each produced in separate sporangia. One type develops into a male gametophyte and the other into a female gametophyte. 2.spores undergo mitosis while remaining inside their sporangia. As a consequence, the gametophytes develop while they are attached to and supported by the sporophyte. Ovule and pollen produced. 3. pollination. Male gametophyte produces male gametes, so pollination eliminates the need to release swimming sperm into the environment. The male gametophyte must germinate and grow through the tissues of the ovule to deliver the male gametes to the egg. 4. maturation of a fertilized ovule into a seed.

The fossil record indicates that angiosperms first appeared about how long ago?

140 million years ago

Spermatophyta (spermato=seed, phyte=plant)

2 main types of seed plants: 1. gymnosperms, which include conifers such as pine trees 2. angiosperms, which are the flowering plants

Which of the statements is true?

All mosses have leaf-like photosynthetic structures.

Which of the statements is correct about hormone actions in plants?

All of these choices are correct. Plant hormones play a central role in plant development, plant hormones influence cell growth and differentiation, plant hormones may alter patterns of gene expression and rates of cell division, most plant hormones are effective in extremely low concentrations.

Which of the statements regarding angiosperms is true?

Although the appearance of angiosperms coincided with a decrease in the overall diversity of other groups of plants, their appearance also influenced the evolution of new species of non-angiosperm plants.

Which features of the sporophyte generation enhance the likelihood of successful spore dispersal?

An erect morphology and the ability to dry out before releasing spores.

If you examine a bracken leaf closely, you may find tiny brown packets along its lower margin. These are sporangia, and each contains diploid cells that undergo meiosis to generate haploid spores. Each spore becomes covered by a thick wall containing sporopollenin, making it well suited for dispersal through the air.

As the sporangia dry out, they break open, releasing the spores.

vegetative reproduction

Asexual reproduction by growth and fragmentation. -horizontal stems

_____ and _____ are structures formed in the fruiting bodies of dikaryotic (n + n) fungi that produce spores.

Basidia; asci

Which of the statements about spores is false?

Both sexual and asexual spores are produced by meiosis.

Which letter on the phylogenetic tree indicates the ancestor of all seed plants?

C

_____ plants are able to reduce photorespiration by creating a _____ concentration of _____ in bundle sheath cells where the Calvin cycle occurs.

C4; high; CO2

A thin band of hydrophobic material that prevents water passage between cells is associated with the endodermis. This band is called the:

Casparian strip.

Which of the statements best defines cavitation?

Cavitation is the formation and expansion of gas bubbles in the xylem.

Which three species make up more than two-thirds of human food consumption?

Corn, rice, and wheat

Which of the statements correctly describes a difference between sexual reproduction and parasexuality?

Crossing over occurs during mitosis in parasexual fungi and during meiosis in sexually reproducing fungi.

Alternation of generations

Every plant species alternates between two multicellular forms: a haploid gametophyte generation that makes gametes (enhance fertilization) and a diploid sporophyte generation that makes spores (enhance dispersal).

Bryophytes possess lignin in their xylem.

False

What is the primary reason that fungi are important in the carbon cycle?

Fungi are able to reach incredibly large sizes. Their high ratio of surface area to volume allows them to decompose large amounts of dead and decaying material, thereby returning carbon to the atmosphere.

Which comparisons of fungal and animal nutrition is correct?

Fungi digest and then absorb food, whereas animals ingest and then digest food.

Ferns and horsetails form a monophyletic group that is the sister group to the seed plants. Most ferns have distinctive leaves that uncoil during development from tightly wound "fiddleheads".

Horsetails, as well as whisk ferns and their relatives, lack this feature. Whisk ferns have photosynthetic stems without leaves and roots, so they look similar to fossils of early vascular plants.

Which of the statements is correct regarding C4 plants as compared with CAM plants?

In C4 plants, CO2 capture and the Calvin cycle happen in different cell types, whereas in CAM plants, CO2 capture and the Calvin cycle happen at different times.

Chara has a multicellular body as well, but it consists entirely of haploid (1n) cells. In animals, haploid gametes are formed by meiosis.

In Chara, haploid eggs and sperm are formed instead by mitosis. The egg is retained within the female reproductive organ, while the sperm are released into the water.

polypod ferns lack mechanism to disperse spores into air.

In contrast, most ferns have a distinctive sporangium (called a leptosporangium). When the spores mature, the sporangium dries out and these cells contract like a catapult, forcibly flinging the spores into the air.

In angiosperms: The male gametophyte has only 3 cells: one cell controls the growth of the pollen tube, while the other two are male gametes or sperm.

In most angiosperms, the female gametophyte contains only 8 nuclei, arranged as 6 haploid cells (one of which gives rise to the egg) plus a central cell containing two nuclei. -During pollination, the two sperm travel down the pollen tube and enter the ovule. One of the sperm fuses with the egg to form a zygote, just as occurs in all plants. The other sperm unites with the two haploid nuclei in the central cell to form a triploid (3n) cell. This triploid cell undergoes many mitotic divisions, forming a new tissue called endosperm. In angiosperm seeds, this endosperm supplies nutrition to the embryo.

sporangium

In plants, a multicellular structure in which haploid spores are formed by meiosis.

Which of the statements accurately describes the role of insects in early angiosperm evolution?

Insect pollination may have allowed early angiosperms to thrive in the understory habitats of tropical rain forests.

Sugar loaded into the source end of the phloem draws water into the sieve tubes by osmosis, raising the pressure. What happens to the water at the sink end?

It follows the sugars out of the sieve tubes via osmosis.

A scientist collects a spore from a new species of fungus and observes that this spore has a flagellum. What does the presence of a flagellum suggest about the lifestyle of this species?

It is aquatic

Why was finding varieties with reduced internode elongation a key step in the breeding of Green Revolution varieties?

It kept the stem from falling over under the weight of a larger seed head.

Which of the statements about lichens is false?

Lichens are symbiotic relationships between a fungus and a plant.

Which factor is thought to limit the stature and productivity of the gametophyte generation?

Limited by the reliance on surface moisture for both fertilization and hydration.

Bryophytes produce their gametes near the ground, where they are most likely to encounter a continuous film of water. They tend to be small, as sperm are able to swim only a few centimeters.

Many bryophytes release their sperm only when agitated by raindrops. Raindrops signal the presence of surface water, and their impact can splash sperm farther than they could swim on their own.

Which of the traits were likely present in the last common ancestor of bryophytes?

Multicellular sporophytes

Which of the statements does not describe a function of the vascular cambium?

New cells produced by vascular cambia result in an increase in stem length.

Which of the statements describes the hypothesis proposed to explain the regular arrangement of leaves around the stem?

New primordia initiate where auxin accumulates, while existing primordia efficiently drain auxin from the meristem surface. This ensures that new primordia form in the location farthest from existing primordia.

A gardener is digging up some of her strawberry plants. She thinks that strawberries reproduce via vegetative reproduction; however, she finds no evidence of horizontal stems connecting her strawberry plants. She concludes that she has a population of strawberry plants that reproduce sexually versus asexually. Is her conclusion correct?

No, her conclusion is incorrect. Horizontal stems can be transient structures and may degrade or disappear over time. Thus, there may be no visible evidence of vegetative reproduction.

pines (most of life cycle is in cones) Pollen carried by wind

Ovulate cones-on upper branches and produce (4 haploid spores-3 degrade) spores that develop into female gametophytes. Triggered by pollen landing on ovule. Pollen cones- clusters near the tips of branches lower in the tree; they produce spores that develop into male gametophytes. only 4 cells at the time the pollen is released from the parent plant.

Flower development-female reproductive structure

Ovule development begins with the growth of sporangia (2 protective layers) Within each sporangium a single cell undergoes meiosis, forming four haploid spores. 1 spore develops into a multicellular female gametophyte. --pollen reaches ovules by landing on stigma and germinate to produce a pollen tube that grows down through the style.

If a special fungicide killed all of the glomeromycetes in an environment but did not affect other types of fungi, which of these would most likely occur?

Plant nutrient uptake from the soil would be reduced.

Which of the statements regarding redwood trees is true?

Redwoods can reproduce via vegetative reproduction, with new shoots appearing on fallen horizontal redwood trees.

Which of the statements could help explain how seed plants came to dominate land environments starting from about 200 million years ago?

Seed plants do not require external water for fertilization.

A seed consists of an embryo, stored resources, and an outer, protective coat.

Seeds increase the probability that offspring will survive because their stored resources can be used to fuel the early growth of the next generation.

Most fern photosynthetic surfaces are divided into smaller units called pinnae. -Bcuz most ferns are not capable of secondary growth: Stems grow underground, only leaves emerge into the air.

Small unit of the photosynthetic surface on fern leaves; also, the external structure of mammalian ears that enhance the reception of sound waves contacting the ear.

Flower development-male reproductive structure

Stamen: prod. pollen -anther:contains sporangia. W/in sporangium, many cells undergo meiosis to form haploid spores -male gametophyte then develops within the spore wall, forming pollen -anther splits open, exposing the pollen grains. Once exposed, the pollen can come into contact with the body of a visiting pollinator or be carried off by the wind.

How do bryophytes obtain water and CO2?

They absorb both CO2 and water directly from the environment without passing through stomata or roots.

How did the addition of a sporophyte generation contribute to the success of plants on land?

The addition of a 2nd generation meant that natural selection could lead to traits (such as an erect form) that enhanced dispersal, w/out simultaneously decreasing the chances of fertilization.

If the stomata of bryophytes and of vascular plants are not the result of convergent evolution, what is an alternative explanation for their appearance in these groups?

The alternative explanation is that stomata evolved once, in the common ancestor of mosses, hornworts, and vascular plants.

How are the zygote and the dikaryotic stages of a fungal life cycle related?

The dikaryotic stage gives rise to the zygote through karyogamy.

Which of the statements regarding fern alternation of generations is true?

The diploid zygote will grow to become the sporophyte.

How was plant diversity affected by the evolution of angiosperms

The diversity of non-angiosperm groups decreased but the total number of plant species increased.

Which of the statements about seed plants is false?

They all produce fruit, which aids in dispersal.

double fertilization

The process in which two sperm from a single pollen tube fuse with the egg and the two haploid nuclei in the central cell

You purchase two identical houseplants and place them side by side on your windowsill. You water both plants equally. You leave one plant, plant A, alone, but you inject florigen into the cells of the shoot apical meristem of plant B. What would you expect to occur?

The shoot apical meristem of plant B will develop into a flower.

How do bryophytes avoid damage to their tissues from a dry environment?

Their membranes and macromolecules are able to withstand desiccation and rehydration of the cells without damage.

Which of the statements is true of pine trees?

There are two types of cones, ovule cones and pollen cones.

Bryophtes Following fertilization, the diploid zygote develops by mitosis into a multicellular sporophyte, while remaining physically attached to and nutritionally dependent upon the gametophyte.

This sporophyte generation addresses the challenges plants face in dispersing offspring through the air. In bryophytes, the sporophyte produces many haploid spores by meiosis, with these spores then being dispersed to promote spread of offspring.

_____ are shorter and typically narrower than _____.

Tracheids; vessels

Which of the statements about transpiration is true?

Transpiration drives the movement of water from the roots to the leaves.

Which of the statements regarding xylem vessels in angiosperm trees is false?

Vessels are rigid and strong and do not require additional support cells.

Four major events that transformed how plants grow and reproduce. 2. Evolution of xylem & phloem in sporophyte generation.

Xylem transports water and dissolved nutrients, and phloem transports carbohydrates produced by photosynthesis. Xylem and phloem transport water and carbohydrates over longer distances than w/ diffusion, and xylem allows vascular plants to pull water from the soil; provided a competitive advantage in both height and sustained hydration over plants that lacked xylem and phloem.

Double fertilization in angiosperms results in:

a diploid embryo and a triploid endosperm (tissue that supports growth of embryo). --allows angiosperms to be effecient by delaying forming nutritive tissue until after fertilization occurs.

Into which of these structures can an axillary bud develop?

a flower

What is the fundamental reproductive unit that the cones of gymnosperms, flowers of angiosperms, and the reproductive fronds of ferns all share in common?

a leaflike organ bearing sporangia

Which of the organisms undergoes mitosis to become multicellular in both the haploid and diploid phases of its life cycle?

a. liverworts b. angiosperms c. horsetails d. ferns

Auxin has no net charge under the _____ conditions _____ a cell.

acidic; outside

ancient lycophytes evolved additional features convergently with seed plants, including a vascular cambium and

cork cambium that enabled them to form trees up to 40 m tall. the vascular cambium of these lycophytes produced relatively little secondary xylem and no secondary phloem

The waxy substance on leaf surfaces is the:

cuticle

Which gymnosperms are characterized by male and female cones and stems composed of a scant amount of xylem and a large volume of unlignified cells?

cycads

In gymnosperms, the outer tissues of the seed that aid in dispersal and the inner tissues that serve as a store of nutrients for the embryo are:

diploid and haploid respectively

Which of the following materials can serve as food sources for fungi?

elephant dung in the Serengetileaf matter in a New England forestthe fruit in your refrigeratora bear carcass in Siberiaa fallen redwood tree in California

Fungi produce fruiting bodies to:

enhance spore dispersal.

Plants that grow on other plants for structural support, but do not consume nutrients or energy from them, are called:

epiphytes.

In a number of species, including apples, bananas, and tomatoes, a gaseous hormone called

ethylene triggers fruit ripening.

Although plants expend metabolic energy to move both water and carbohydrates between leaves and roots, the transportation of water requires slightly more energy.

false

The development of axillary buds is under the control of a single hormone, cytokinin.

false

The rates of photosynthetic production of CAM plants are higher than C3 plants because they can store carbon until it is needed.

false

Vessel elements must be thinner and shorter than tracheids because they lack the structural integrity to support large angiosperm trees.

false

Which of the groups have a haploid stage of the life cycle that can survive exposure to the air?

ferns bryophytes seed plants

seed coat Can allow them to pass unharmed through an animal's digestive system

formed from tissues that surround the sporangium and, therefore, is a product of the diploid sporophyte.

spore dispersal is enhanced by height whereas

gametophytes must remain small and close to the ground to increase their chances of fertilization.

Which of the substances helps make xylem cells very rigid to avoid collapse?

lignin

In the early 20th century, an experiment was conducted to determine how large the forces are that allow leaves to pull water from the soil. The rate at which water flowed from a reservoir into the cut tip of an actively transpiring plant was _____ the flow rate through the branch tip when it was subsequently attached to a vacuum pump.

greater than

Which generation (in the alternation of generations) is represented by the green, leafy, portion in mosses?

haploid gametophyte

Without the higher rates of transpiration exhibited by angiosperms, many tropical regions would:

have higher temperatures and lower rainfall.

scientific name for land plants is Embryophyta

highlights the fact that in all land plants the fertilized egg is retained and develops in place, forming an embryo.

The persistent and photosynthetic generation of bryophytes is in general constrained to be close to the ground:

in order to successfully disperse gametes.

Where in a growing plant would you expect to find the highest concentration of auxin?

in the apical meristem

Where is carbon stored in a CAM plant prior to its assimilation into sugars?

in the vacuole

When the forces pulling water through the xylem are large, the risk of vessel collapse is _____, and the chance that an air bubble will spread from one vessel to another is _____.

increased; increased

At the tip of each branch, the _____ surround(s) the shoot apical meristem.

leaf primordia

Angiosperm mating systems: self-incompatible

pollination by the same or a closely related individual does not lead to fertilization. Self-incompatible plants must be able to recognize that a gamete comes from a closely related individual. - recognize proteins produced from self-incompatibility genes, or S-genes. If the pollen's proteins match those of the carpel, the pollen either fails to germinate or germinates but the pollen tube grows slowly and eventually stops elongating. Because dozens of S-gene alleles can be present in a population, only pollen transfers between closely related individuals are blocked. [ex: Apples]

Water flows from vessel to vessel through pits, which are:

primary cell walls that separated the neighboring cells as they grew.

Flower development--Whorls

produce neither pollen nor ovules, but instead contribute to reproductive success. Most flowers have two outer whorls. The outermost is made up of sepals, often green but sometimes brightly colored. Sepals protect the flower during its development. -Petals: role is to attract and orient animal pollinators; produce volatile oils. Produce odors—some pleasant, some not—that many flowers use to advertise their presence to pollinators.

apomixis

seeds can develop even in the absence of fertilization. Disperse asexually.

The contents of the xylem sap in plant roots are:

selectively maintained by endodermal cells.

Xylem sap and soil water differ in _____ because of _____.

solute composition; selective uptake by the endodermis

The black spots seen on a moldy piece of bread are:

sporangia


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