CH. 27 BIO

What is the structure labeled as A in the accompanying figure?

gametangium of an alga

What is the structure labeled as 1 in the accompanying figure?

gamete

Heterospory is believed to have led to the evolution of:

seeds

Refer to the accompanying figure. At what point of this life cycle does fertilization occur? (diagram)

4

Refer to the accompanying figure. At what point is there potential to undergo mitosis to become a gametophyte? (diagram)

9

Each archegonium produces many eggs.

False - a single egg

If a plant produces microspores and megaspores, then by definition, it is homosporous.

False - heterosporous

Mosses have stems, roots, and leaves.

False - lack, do not have

Xylem is a vascular tissue that conducts dissolved sugars. ___

False - water and dissolved minerals

What is the purpose of the waxy cuticle in plants?

It prevents desiccation.

Which is the most economically important bryophyte?

Sphagnum

Why are mosses and liverworts limited in size?

They lack vascular tissues.

Modern botanists think that all plants evolved from a common ancestor that was an ancient green algae. What is the best explanation for this hypothesis?

They share many biochemical and metabolic traits.

In algae, gametangia are generally unicellular.

True

What is the male sexual structure that produces sperm in plants?

antheridium

Plants are believed to have evolved from which group of algae?

charophytes

Which is a characteristic shared between green algae and plants?

chlorophylls a and b in plastids

Alternation of generations in plants refers to the alternation of:

diploid and haploid stages.

The leafy fern that you might have as a house plant is the ____ generation.

diploid sporophyte

In plants, the fertilized egg develops into a multicellular ____ (young plant) within a female gametangium.

embryo

Which of the following is a vascular plant?

fern

The sori of most ferns are found on which part of the plant?

fronds

What are the multicellular sex organs in plants?

gametangia

The ____ generation is dominant in mosses, as it can live independently.

haploid gametophyte

The structure in the accompanying figure labeled as 4 is: (diagram)

haploid.

Many seedless plants produce spores of one morphological type, which is referred to as:

homospory.

A key step in the evolution of vascular plants was the ability to produce ____, a strengthening polymer in the walls of cells that function for support and conduction

lignin

The oldest known fossils suggest that the ____ may have been the first plants to inhabit land.

liverworts

The gametophyte generation of ferns is the:

prothallus.

When a moss spore lands in a suitable spot, it germinates and grows into a filament of cells called a:

protonema.

What do ferns lack?

seeds

After sexual reproduction in a moss, the ____ grows out of the gametophyte.

sporophyte

Which vascular tissue is responsible for conducting water and dissolved minerals in plants?

xylem