LAB MIDTERM CHP 20,21

Question 1

Vascular plants (Bryophytes) consist of these 3 phyla:

Answer 1

Phylum Hepatophyta, Phylum Anthocerophyta, and Phylum Bryophyta.

Question 2

The seedless vascular plants consist of ____ and ____.

Answer 2

Club mosses and ferns.

Question 3

The largest group of vascular plants are the ____ ____ and it consists of the ____ and the ____.

Answer 3

Seeded plants; angiosperms, gymnosperms.

Question 4

What is the function of a rhizoid?

Answer 4

The rhizoids extend into the soil and anchor the thallus.

Question 5

Describe asexual and sexual reproduction in Marchantia.

Answer 5

Marchantia (a thalloid liverwort) reproduce asexually through gemma cups which appear on the upper surface of the thallus and contain gemmae. The gemmae detach and grow into a new plant. Sexually, marchantia reproduce through the alternation of generations.

Question 6

Compare and constrast thallus and leafy liverworts.

Answer 6

Thalloid liverworts possess flat leaflike lobed bodies (thalli), and are most commonly found living along creek banks or on moist soil. Leafy liverworts resemble mosses and are commonly found on the bark of trees in tropical and subtropical environments.

Question 7

What is the function of rhyzoids in hornworts?

Answer 7

Rhizoids help anchor the minute plant.

Question 8

Where can one find hornworts?

Answer 8

Hornwarts usually live on moist ground in the shade.

Question 9

Describe two ways in which mosses can reproduce.

Answer 9

Mosses are capable of asexual reproduction through fragmentation, but they undergo an alteration of generation with gametophyte and sporophyte stages.

Question 10

Why was sphagnum successful as a bandage in WWII?

Answer 10

Sphagnum (peat moss) was more absorbant than cotton and has antibacterial properties.

Question 11

Where can Polytrichum sp. be found?

Answer 11

Polytrichum is a common moss found living in bogs.

Question 12

What are 10 reasons we should thank a plant?

Answer 12

Plants provide oxygen, food, shelter, shade, erosion control, and commercial products for human use such as, timber, medicine, and paper.

Question 13

To conqeur land, what sort of adaptations did early land plants have to develop?

Answer 13

Early land plants had to evolve mechanisms that prevent deciccation, anchor the plant, transport water & nutrients, and ensure reproduction.

Question 14

Compare and constrast nonvascular plants with vascular plants.

Answer 14

Vascular plants possess conducting tissues (Xylem & Phloem) which transfer nutrients from the soil throughtout the plants body. Nonvascular plants lack true roots, stems, and leaves.

Question 15

Describe the process of alteration of generations.

Answer 15

The sporophyte (2n) generation releases spores by mitosis. The spores mature into a gametophyte (n) which release gametes by mitosis which fuse to form a zygote (2n). The zygote matures into a sporophyte.

Question 16

Name several characteristics of phylum hepatophyta.

Answer 16

Liverwort leaves lack a thick midrid, have both small & larger leaves, and are flattened into a single plane instead of radiating out in different directions. Many form mycorrhizal relationships with fungi.

Question 17

Name several characteristics of phylum antherocerophyta.

Answer 17

Hornwarts are small. The thallus body has pores and cavities filled with mucilage. Many possess cyanobacteria that live in the rich mucous. Stomata are present on the sporophyte.

Question 18

Name several characeristics of phylum bryophyta.

Answer 18

The blades of the “leaf” are one cell layer thick, lack vascular tissue and stomata, and surround a thickened midrib.

Question 19

What are stems?

Answer 19

Stems are vascular plant organs that support leaves and reproductive structures.

Question 20

What are roots?

Answer 20

Plant organs that absorb water and nutrients from the soil and anchor the plant.

Question 21

What are leaves?

Answer 21

Leaves are the primary photoynthetic organs of plants.

Question 22

Today, these three phyla represent seedless vascular plants.

Answer 22

Sphenophyta (horsetails), Psilotophyta (whisk ferns), and Pterophyta (ferns).

Question 23

Seedless vascular plants reproduce by producing

Answer 23

spores via spore-producing bodies known as sporangia.

Question 24

Describe several uses of Lycopodium.

Answer 24

Lycopodium has been used in homeopathic remedies as emetic, baby powder, and worming agent. At christmas, gound pines are used for decorations. Lycopodium has been used as a stabilizer in ice cream. The spores have been used in controlles explosions.

Question 25

Where can one find Selaginella?

Answer 25

Selaginella can be found in moist areas worldwide, and appear to creep along the ground with simple, scalelike leaves on branching stems from which roots also arise.

Question 26

Compare and contrast megaspores and microspores.

Answer 26

The megaspores are large spores that develop into a female gametophyte, which eventually produces egg cells. The microspores are spores that develop into a male gametophyte, which fertilizes the megaspore.

Question 27

Compare and contrast megaspores and microspores.

Answer 27

The megaspores are large spores that develop into a female gametophyte, which eventually produces egg cells. The microspores are spores that develop into a male gametophyte, which fertilizes the megaspore.

Question 28

What is the common name for members of phylum Psilotophyta?

Answer 28

Whisk ferns.

Question 29

Where is Psilotum usually found?

Answer 29

Psilotum spp. are commonly found in warm moist regions in the southern United States.

Question 30

Describe several distinguishing features of phylum Psilotophyta.

Answer 30

The small plant has no leaves or roots and a dichotomously branching green stem with small scales that bears bright yellow synangia on lateral branches. A synangium is formed from three fused sporangia on short lateral branches. Psilotum spp. are homosporous. A horizontal rhizome gives rise to an aerial stem.

Question 31

What is a whisk fern?

Answer 31

Whisk ferns are members of phylum Psilotophyta. The small plant has no leaves or roots and a dichotomously branching green stem with small scales that bears bright yellow synangia on lateral branches.

Question 32

What was calamites?

Answer 32

Calamites spp. were giant members of the horsetail family that grew to heights of more than 20m during the Carboniferous.

Question 33

Describe several uses of horsetails.

Answer 33

Through the centuries, horsetails have been used as food and medicine. Today, however, the consumption of horsetail is discouraged. Medically, ancient cultures used horsetail as diuretics; astringents; agents to discourage lice, eas, and mites; and a cure for diarrhea. Many Oriental gardens feature horsetails. Pioneers used horsetails to scrub pots and sharpen knives.

Question 34

Given the description of elators provided on p. 327, describe their function.

Answer 34

Elaters are winglike structures found on the spores of horsetails. They serve to increase the distribution of the spores.

Question 35

What are the general characteristics of seedless vascular plants?

Answer 35

The seedless vascular plants, as the name indicates, do not produce seeds but, instead, reproduce through the production of spores. These plants feature a dominant sporophyte generation and a reduced gametophyte generation.

Question 36

Distinguish between the sporophyte and the gametophyte generation in seedless vascular plants.

Answer 36

These seedless vascular plants feature a dominant sporophyte generation and a reduced gametophyte generation.

Question 37

What are some commercial and medical uses of seedless vascular plants?

Answer 37

Seedless vascular plants, such as ferns, are used in medicine and as ornamentals. Horsetail can be used as medicine and to sharpen knives. Lycopodium spp. are used as decoration and, at one time, in camera ashes.

Question 38

Compare and contrast Lycopodium sp. and Selaginella sp.

Answer 38

Selaginella spp. appear to creep along the ground with simple, scalelike leaves on branching stems from which roots arise. The leaves of Selaginella spp. have a distinct ligule, or tongue, on their upper surface and generally appear larger than Lycopodium spp. In Lycopodium spp., an underground stem branches horizontally across the surface, producing aerial stems and underground roots. The surface of the aerial stem is covered by small, closely and spirally packed, scalelike leaves.

Question 39

How did the pioneers use horsetail?

Answer 39

Pioneers used horsetail to scrub pots and sharpen knives.

Question 40

What is the signi cance of the vast fern forests of the Carboniferous?

Answer 40

Many of the coal deposits of today were formed from Carboniferous forests.

Question 41

What is the function of a sporangium?

Answer 41

The function of sporangia is to produce haploid spores through meiosis.