Chapter 23

In the alternation of generations, what is formed when a spore germinates?

A haploid stage called the gametophyte

What are lichens?

A symbiotic association of algae and fungi

In which environment would you most likely find chytrids?

A warm swamp

Which of these hormones helps plants tolerate drought and cold?

Abscisic acid

________ maintains seed dormancy, and ________ ends seed dormancy by stimulating enzymes that break down the food reserves of the seed to fuel seedling growth.

Abscisic acid; gibberellin

Cup fungi are in the phylum _____.

Ascomycota

Where are apical meristems located?

At the tips of roots, shoots, and branches

Plasmogamy is indicated by the letter _____.

B fusion of cytoplasm

How are lichens and mycorrhizae similar?

Both form symbiotic relationships with plants that benefit the plants

Which of the following supports the idea that land plants arose from green algae?

Both utilize chlorophylls a and b.

How does carbon dioxide enter a leaf?

CO2 passes through openings called stomata on the leaf surface.

________ causes human yeast infections.

Candida albicans

Which of the following features are characteristic of fungi?

Cell walls, feeding by absorption, and usually filamentous bodies

Which polysaccharide is produced by both fungi and arthropods?

Chitin

What is the role of chlorophyll in plants?

Chlorophyll captures solar energy that the plant can convert to other forms of energy

Which fungal group produces swimming, flagellated spores?

Chytrids

Which of these tissue types is (are) found throughout young plant bodies?

Epidermis, xylem, and phloem

Which of the following weather conditions would you expect to have the greatest negative impact on the sexual reproduction of ferns and mosses?

Excessively dry for several days

Why can't you buy fern seeds from a garden supply store?

Ferns do not produce seeds.

Which group does not depend on water for reproduction?

Flowering plants

What major adaptations contributed to the success of the angiosperms?

Flowers and fruits Broad leaves

If you were hiking and wanted to show off your understanding of the differences between gymnosperms and angiosperms, what characteristics could you see with your naked eye that would help you impress your friends?

Flowers or cones

How do fungal cells differ from most plants and animal cells?

Fungal cell walls are made up primarily of chitin, a compound that is also found in the hard shells of crustaceans. No cellulose is present in fungal cell walls. Fungi also lack the chloroplasts found in plant cells, as they do not undergo photosynthesis.

Rusts and smuts are examples of

Fungal plant diseases

What ecological consequences would occur if humans, using a new and deadly fungicide, destroyed all fungi on Earth?

Fungi decompose almost anything that has died or that is decaying. Without fungi, the majority of the death would overtake earth and make it virtually uninhabitable for any living organisms. Fungi live by eating dead things, but without fungi, all the dead things would never be recycled.

________ form beneficial symbiotic relationships with plant roots.

Glomeromycetes

Which group of plants was the first to produce seeds?

Gymnosperms

Fruit production requires precious resources. What important benefit does fruit provide?

Is a means of seed dispersal

Which of these statements is true about the gametophyte tissue that surrounds the pine embryo?

It functions as a haploid food reserve.

What produces the plant cuticle and what is its function?

It is secreted by epidermal cells and helps to retard water loss from the plant.

What cell type permits the continued growth of a plant throughout its life?

Meristem cells

Describe two symbiotic relationships between a fungus and another organism. In each case, explain how each partner in these associations is affected.

Mutualism, commensalism, and parasitism. Mutualism: both partners benefit. An example of mutualism is the relationship between the Egyptian plover and the crocodile. The plover eats a meal and the crocodile gets his teeth cleaned. Commensalism: only one species benefits while the other is neither helped nor harmed. For example, remora fish are very bony and have a dorsal fin (the fin on the back of fish) that acts like a suction cup. he remora fish gets a meal, while its host gets nothing. Parasitism: One organism (the parasite) gains, while the other (the host) suffers. The deer tick is a parasite.

Which of the following characteristics helps differentiate between a monocot and a dicot?

Number of flower parts

Ascomycetes produce which of the following?

Penicillin

What type of tissue transports sugars (the product of photosynthesis) throughout the plant?

Phloem

Which of the following is "male" in the life cycle of angiosperms?

Pollen grain

Which of these pathways best summarizes the route of a mineral that is absorbed by a plant?

Root hairs - epidermis - cortex - endodermis - pericycle - xylem

Which of the following are important reproductive adaptations that allow plants to inhabit terrestrial environments?

Seeds and pollen

Which of these plant cells is alive but has no nucleus?

Sieve-tube element

Which of the following is a characteristic of nonvascular plants?

Small size

Why are mosses and liverworts dependent on water for reproduction?

Sperm must swim through water to reach and fertilize eggs.

Spores and gametes are both haploid reproductive cells. What is the difference between the two?

Spores germinate and grow into a multicellular haploid gametophyte, and gametes fuse to form a diploid zygote.

Stomata are pores found in the leaves and stems of plants. What is the function of stomata?

Stomata open to allow gas exchange and close to conserve water.

Which of the following is a common function of stems but NOT of roots?

Support

Which of the following sequences describes sexual reproduction in the fungal life cycle?

The diploid zygote divides by meiosis to form haploid spores, which produce haploid mycelia through mitosis.

How does a plant benefit from an association between the plant's roots and a fungus?

The fungus processes soil nutrients and minerals and passes those from soil to the root cells of the plant.

Describe the structure of the fungal body.

The main body of most fungi is made up of fine, branching, usually colourless threads called hyphae. Each fungus will have vast numbers of these hyphae, all intertwining to make up a tangled web called the mycelium.

If a beaver eats the bark all the way around a tree trunk (a process called "girdling"), why does the tree die?

The phloem is damaged, and the transport of sugars ceases.

In flowering plants, what is the relationship between the sporophyte and gametophyte?

The sporophyte is dominant, and the gametophyte is retained on the sporophyte

Which of the following statements about the function of flowers is TRUE?

They attract pollinators.

Describe asexual reproduction in fungi.

They reproduce asexually by producing lightweight spores, which enable the fungi to disperse vast distances on the wind. Fungi reproduce asexually by fragmentation, budding, or producing spores. Fragments of hyphae can grow new colonies. Mycelial fragmentation occurs when a fungal mycelium separates into pieces with each component growing into a separate mycelium.

What would you expect to be missing in a plant that exhibits primary growth but not secondary growth?

Thick woody branches

List the major taxonomic groups of fungi, describe some key features of each group, and give an example of a fungus in each group.

Zygomycota~ formation of a zygospore during sexual reproduction and the lack of hyphal cell walls except in reproductive structures; black bread mold Ascomycota (sac fungi)~reproduce by budding and fission, yeasts also engage in sexual reproduction that results in the production of an ascu; Pezizales Basidiomycota (club fungi)~ production of forcibly discharged ballistospores; Grilled Muschrooms Deuteromycota (fungi imperfecti)~well-developed, septate mycelium with distinct conidiophores but some have a unicellular thallus;Hyphomycetes

The photosynthetic component of a lichen is a(n)

alga or cyanobacterium.

Apple trees are ______________, flowering plants whose seeds are encased within ovaries that may mature into fruit

angiosperms

Pollen production by the anthers of a flower is characteristic of

angiosperms

A stamen consists of _____.

anther and filament

In moss, _____ produce sperm.

antheridia

In pines, the female gametophyte contains _____, each of which contains a(n) _____.

archegonia ... egg

In sac fungi, karyogamy and meiosis occur in _____.

asci

Roots grow downward and shoots grow upward due to

auxin

Elongation of cells in stems is promoted by

auxins and gibberellins.

In club fungi, karyogamy and meiosis occur in _____.

basidia

The specialized reproductive structures of club fungi are called

basidia

If a tree's heartwood rots out, the tree will

be weaker than normal and more likely to blow over in a storm.

You discover a new species of plants in a tropical rainforest. You observe that it has flagellated sperm and the sporophyte emerges from the gametophyte; however, seeds and xylem tissue is lacking. This plant is probably a(n)

bryophyte

How can you determine the approximate age of a tree growing in temperate climates?

by counting annual rings

Fungal cell walls are different from plant cell walls because fungal walls contain

chitin, whereas plant walls have cellulose.

Which of these characteristics is shared by algae and seed plants?

chloroplasts

_____are gymnosperms that reproduce by means of seeds formed inside cones

conifers

Periderm consists of mostly

cork cells.

To limit water loss, land plants developed

cuticle

_____is a waxy coating that covers the epidermis of of many land plants and limits the evaporation of water

cuticle

Which of the following are gymnosperms?

cycads, ginkgos, and conifers

As a group, fungi are _____.

decomposers

Of the major tissue systems associated with land plants, the ________ tissue system covers the outer surface of the primary plant.

dermal

Which of the following is responsible for regulating the movement of oxygen and carbon dioxide between the plant and the surrounding atmosphere?

dermal tissue system

What type of cells do mature leaves contain?

differentiated

Fungi usually obtain food by

digesting it externally and then absorbing it

In the moss life cycle _____ cells within a sporangium undergo _____ to produce _____ spores.

diploid ... meiosis ... haploid

The conspicuous part of a fern plant is a _____.

diploid sporophyte

Karyogamy produces a _____.

diploid zygote

In general, the plant life cycle has evolved from ________ to ________.

dominant gametophyte; dominant sporophyte

Which of these is unique to flowering plants?

double fertilization

In flowering plants one megaspore gives rise to _____ nuclei.

eight haploid

The dermal tissue system consists of

epidermis

A nucleus within an ascus undergoes meiosis, producing four haploid spores, which then undergo mitosis, producing eight haploid ascospores. These haploid ascospores contain a maximum of _____ different genetic types.

four

The antibiotic penicillin was originally derived from

fungi

All the following are true of companion cells EXCEPT that they

fuse together to form the sieve plates of sieve-tube elements.

In plants, the haploid, single-celled product of mitosis is a

gamete

The spores develop into a haploid ____________ generation which produces sperm and eggs by mitosis. These fuse and produce a diploid zygote, and the life cycle begins again.

gametophyte

If you see moss near the base of a tree in your yard, the green leafy moss plants are

gametophytes

In plants, the haploid, multicellular organism is the

gametophytes

Seed germination is stimulated by

gibberellin

Tomatoes that are planted upside down still grow upright, displaying

gravitropism

Ginkgos are _______________, plants whose seeds are not encased in an ovary.

gymnosperms

Fungi produce _____ spores.

haploid

The cells of a gametophyte are

haploid

The dominant generation in the fungal life cycle is usually

haploid

In the pine, microsporangia form _____ microspores by _____.

haploid ... meiosis

In the alternation of generations life cycle, adults may be

haploid or diploid

Zygosporangia are _____.

heterokaryotic

In pines, an embryo is a(n) _____.

immature sporophyte

An onion bulb is made up of ________ that are specially adapted for food and water storage.

leaves

Pollen and seeds evolved in response to

living on dry land

Basidia produce spores by a process known as _____.

meiosis

Photosynthesis occurs in the __________.

mesophyll

In pine trees, pollen grains get to the ovule via the _____.

micropyle

In mosses gametes are produced by _____; in ferns gametes are produced by _____.

mitosis ... mitosis

The sperm produced by mosses require _____ to reach an archegonium.

moisture

A complete lack of vascular tissue is characteristic of

mosses

The mat-like structure composed of hyphal threads that forms the body of most fungi is called a(n)

mycelium

The interwoven mass of cells that forms large structures such as an earthstar or a mushroom is a

mycelium.

Glomeromycete fungi form __________ with plants to create a beneficial relationship.

mycorrhizae

Some fungi are predators (not parasites) of

nematodes (roundworms).

Bacteria-containing nodules in the roots of legume plants aid in the utilization of

nitrogen

Where do fern antheridia develop?

on the underside of the gametophyte

Of the four haploid cells produced by a pine cone's megasporocyte (megaspore mother cell), _____ survive(s).

one

Which of the following is the definition of a sieve-tube element?

one of two cell types found in phloem that join end to end to form transporting pipes called sieve tubes

______are structures within the ovaries of flowers inside which female gametophytes develop.

ovules

A long-term relationship between two organisms where one organism is harmed is called __________.

parasitism

Most of the interior of a leaf consists of soft, thin-walled, living ________ cells.

parenchyma

In a dicot stem, the ________ is between the vascular cambium and the cork cambium.

phloem

What plant part is described by the following: a transport structure that moves a solution containing a variety of organic molecules, including sugars, amino acids, and hormones, up or down the plant to structures that need them?

phloem

Mycorrhizae are symbiotic associations between

plant roots and a fungus.

In angiosperms, what is the male gametophyte?

pollen

The male gametophytes of flowering plants are also referred to as _____.

pollen grains

_____are tiny male gametophytes that carry sperm-producing cells. They are dispersed by wind or airborne insects

pollen grains

Which of the following features distinguishes plants from other photosynthetic organisms?

presence of protected, multicellular embryos

Molds easily contaminate foods because fungi

produce huge numbers of airborne spores.

Ethylene

promotes leaf and fruit drop.

Auxin

promotes phototropism.

On the tip of the root, the apical meristem forms the ________, which prevents the meristem from being worn away as it pushes through the soil.

root cap

Many root epidermal cells grow projections called ________, which extend from their surface and help in the absorption of water and minerals.

root hairs

Mycorrhizae are symbiotic associations between fungi and plant

roots

As an oak tree ages, the trunk becomes thicker and woodier due to ________ growth.

secondary

In flowering plants the integuments of the ovule develop into a(n) _____.

seed coat

In ascomycetes, the ascus functions in

sexual reproduction

What are the two major cell types that compose phloem?

sieve-tube elements and companion cells

In vascular plants, sugar solutions and hormones are transported through tubes constructed of cells called

sieve-tube elements.

Certain cells of sporophytes undergo meiosis to produce haploid reproductive cells called __________.

spores

The sporophyte produces

spores by meiosis.

An oak tree

sporophyte

In plants, the diploid, multicellular organism is the

sporophyte

In the life cycle of a fern, the large fern plant that we normally see is the

sporophyte

In the life cycle of most plants, a diploid ________ generation produces haploid spores through meiotic cell division.

sporophyte

The multicellular diploid form of the flowering plants is called the __________.

sporophyte

With respect to plant reproduction, there has been an evolutionary trend toward

sporophyte prominence.

The sexual life cycle of plants is described as alternation of generations because it alternates between

sporophytes and gametophytes.

Both plants and green algae store food as

starch

In angiosperms, pollination is the transfer of pollen grain to the _____ of a flower on the same plant or another plant of the same species.

stigma

A carpel is composed of _____.

stigma, style, ovary

Pores called______ in leaves and stems open to allow gas exchange but close when water is scarce, reducing the amount of water lost to evaporation.

stomata

The closest living relatives to plants are

stoneworts

Fungi release digestive enzymes into their _____.

surroundings

Which of these contains two haploid nuclei?

the heterokaryotic stage of the fungal life cycle

A zygosporangium is produced by

the union of two haploid hyphae.

The name sac fungi is appropriate for the ascomycetes because

they produce spores in saclike structures.

Water-conducting cells that have a small diameter and tapered ends are called

tracheids.

Most gymnosperms are pollinated by

wind

What part of the plant is responsible for transporting water to the leaves of an angiosperm?

xylem

Single-celled fungi are known as

yeasts

Black bread molds produce diploid reproductive structures called

zygosporangia

A fertilized egg is a

zygote