Chapter 28- Green Algae and Land Plants

Lignin

is a complex polymer built from six- carbon rings.

Natural selection

favored early land plants with three main adaptations that solved the drying problem by:

Individuals

are anchored to soil, rocks, or ee bark by structures called rhizoids.

Sporopollenin

is a waxy substance (similar to cuticle) that encases the spores and pollen of modern land plants and helps them resist drying.

Angiosperms

can be annual (have a single growing season) or perennial (live for many years), with life spans ranging from a few weeks to several thousand years.

Green algae

and land plants provide ecosystem services because they enhance the life- supporting attributes of the atmosphere, soil, surface water, and other physical components of an ecosystem.

Megaspores

develop into female gametophytes, which produce eggs by mitosis.

Microspores

develop into male gametophytes, which produce sperm by mitosis.

stoma

A(n) consists of an opening surrounded by specialized guard cells.

Megasporangia

(singular: ) are spore- producing structures that produce megaspores.

Microsporangia

(singular: ) are spore- producing structures that produce microspores.

carpel

A(n) contains a protective structure called an ovary, where the ovules are found.

tough protective

A seed consists of an embryo and a store of nutritive tissue, surrounded by a(n) layer.

Flowers

are attractive because they provide pollinators with food in the form of protein- rich pollen or a sugar rich fluid known as nectar.

Cuticle

is a watertight barrier that coats the aboveground parts of today s land plants and helps them resist drying.

Tracheids

are long, thin, tapering cells that have the following components:

Spores

were produced that resist drying.

Heterospory

is the production of two distinct types of spores by different structures.

gametangium

The egg- producing is called an archegonium.

alternation of generations

When occurs, individuals exist in either a multicellular haploid or diploid phase.

Homospory

is the production of a single type of spore.

Gametes

were produced in complex, multicellular structures.

sperm nuclei

The involvement of two is called double fertilization.

Vessel elements

are shorter and wider than tracheids, and their upper and lower ends have perforations where both the primary and secondary cell walls are missing.

Pollination

is the transfer of pollen from one plants stamen to another plant s carpel.

heterosporous seed plants

In , the microspore germinates to form a tiny male gametophyte that is surrounded by a tough coat of sporopollenin, resulting in a pollen grain.

physical components

An ecosystem consists of all the organisms in a particular area, along with of the environment such as the atmosphere, precipitation, surface water, sunlight, soil, and nutrient.

vascular plant

In the stems and branches of some species, tracheids or a combination of tracheids and vessels form the extremely strong support material called wood.

adaptive radiation

A(n) occurs when a single lineage produces a large number of descendant species that are adapted to a wide variety of habitats.

gametangium

The sperm- producing is called an antheridium.

Microsporangia (singular

microsporangium) are spore-producing structures that produce microspores

Megasporangia (singular

megasporangium) are spore-producing structures that produce megaspores