Biology, Ch 30

anther

In an angiosperm, the terminal pollen sac of a stamen, where pollen grains containing sperm-producing male gametophytes form.

endosperm

In angiosperms, a nutrient-rich tissue formed by the union of a sperm with two polar nuclei during double fertilization. Provides nourishment to the developing embryo in angiosperm seeds.

ovary

In flowers, the portion of a carpel in which the egg-containing ovules develop.

Most human food comes from _______.

angiosperms

All angiosperms are classified in a single phylum called:

anthophyta

With respect to angiosperms, which of the following is incorrectly paired with its chromosome count? a. egg - n b. megaspore - 2n c. microspore - n d. zygote - 2n e. sperm - n

b. megaspore - 2n

What influenced the evolution of plants, and vice versa? a. insects b. flying saucers c. animals

c. animals

seed

consisting of an embryo and nutrients within a protective coat. can disperse over LONG distance by wind or other means

ovule

consists of a megasporangium +megaspore + protective integuments A structure that develops within the ovary of a seed plant and contains the female gametophyte.

Bears "naked" seeds, typically on cones

gymnosperms

Extant seed plants for two sister clades called:

gymnosperms angiosperms

Gymnosperms

have one integument

derived traits of seed plants:

heterospory ovules pollen seeds reduced gametophytes

angiosperms have ________ integument(s)

two

double fertilization occurs when the pollen tube discharges ________ sperm into the female gametophyte within an ovule

two

pollen eliminates the need for a film of _______ and can be dispersed great distances by air or animals

water

A seed may remain dormant for days to _______, until conditions are favorable for germination

years

double fertilization

A mechanism of fertilization in angiosperms, in which two sperm cells unite with two cells in the embryo sac to form the zygote and endosperm.

micropyle

A pore in the integuments of an ovule

progymnosperm

An extinct seedless vascular plant that may be ancestral to seed plants.

Explain why plant diversity may be considered a non-renewable resource

Because extinction is irreversible, it decreases the total diversity of plants, many of which may have brought important benefits to humans.

Compare and contrast a pine cone and flower in terms of structure and function.

Both - have sporophylls (leaves that produce spores) pine cone structure- separate pine cones and ovulate cones flower pollen grains are produced by anthers of stamens ovules are within the ovaries of carpels produce both pollen and ovules

This phylum is the largest of the gymnosperm phyla have mostly woody cones most can carry out photosynthesis all year round

Coniferophyta

style

The stalk of a flower's carpel, with the ovary at the base and the stigma at the top.

pollination

The transfer of pollen to the part of a seed plant containing the ovules, a process required for fertilization.

It has been said that an oak is an acorn's way of making more acorns. Write an explanation that includes these terms: sporophyte gametophyte ovule seed ovary fruit

The tree (sporophyte) produces flowers, which contain gametophytes in pollen grains and ovules Eggs in ovules are fertilized mature ovaries develop into dry fruits called acorns

Angiosperms originated at least

140 million years ago

Six crops yield _____% of the calories consumed by humans

80%

dicots

Flowering plant whose embryos have 2 cotyledons (seed leaves).

How are various gymnosperms similar yet distinctive?

Gymnosperms do not have seeds enclosed in ovaries and fruits Some gymnosperms have small cones that look like berries, but are not fruits leaf shape varies - needles to palm- like leaves

heterosporous plants produce what?

Heterosporousplants produce two types of spores, which develop into either male or female gametophytes

pollen grain

In seed plants, a structure consisting of the male gametophyte enclosed within a pollen wall.

monocots

Member of a clade consisting of flowering plants that have one embryonic seed leaf, or cotyledon.

eudicot

Member of a clade consisting of the vast majority of flowering plants that have two embryonic seed leaves, or cotyledons.

basal angiosperm

Member of a clade of three early-diverging lineages of flowering plants. Examples are Amborella, water lilies, and star anise and its relatives.

magnoliid

Member of the angiosperm clade most closely related to eudicots. Extant examples are magnolias, laurels, and black pepper plants.

conifers

Member of the largest gymnosperm phylum. Most conifers are cone-bearing trees, such as pines and firs.

three key features of gymnosperm life cycle:

Miniaturization of their gametophytes Development of seeds from fertilized ovules The transfer of sperm to ovules by pollen

Monocots vs. Dicots

Monocots - 1 leaf, veins scattered/parallel, flowers come in multiples of 3,6,9. Dicots - 2 leaves, circular veins/netted, tap root

What additional features of seed plants, not present in seedless plants, have contributed to the enormous success of seed plants on land?

Reduced gametophytes of seed plants are nurtured by sporophytes and protected from stress, such as drought and UV radiation. Pollen grains have tough protective walls. Seeds have one or two layers of protective tissue, the seed coat, that improve survival by providing more protection from environmental stresses that do the walls of spores. Seeds contain stored supply of embryos with nourishment for growth.

Contrast sperm delivery in seedless vascular plants with sperm delivery in seed plants

To have any chance of reaching the eggs, the flagellated sperm of seedless vascular plants must swim through a film of water, usually over a distance of no more than a few centimeters. In contrast, the sperm of seed plants do not require water because they are produced within pollen grains that can be transported long distances by wind or by animal pollinators. Although flagellated in some, the sperm of seed plants do not require mobility because pollen tubes convey them from the point at which the pollen grain is deposited directly to the eggs.

Which of ht following is not a characteristic that distinguishes gymnosperms and angiosperms from other plants? a. alternation of generations b. ovules c. interments d. pollen e. dependent gametophytes

a. alternation of generations

A fruit is commonly; a. mature ovary b. thickened style c. enlarged ovule d. modified root e. mature female gametophyte

a. mature ovary

Gymnosperms and angiosperms have the following in common except a. seeds b. pollen c. vascular tissue d. ovaries e. ovules

d. ovaries

Where in an angiosperm would you find a megasporangium? a. inside the style of a flower b. inside the tip of a pollen tube c. enclosed in the stigma of a flower d. within an ovule contained within an ovary of a flower e. packed into pollen sacs within the anthers found on a stamen

d. within an ovule contained within an ovary of a flower

seed-bearing plants are __________ producers in most terrestrial ecosystems

dominant

Probably should be able to draw the life cycle of a pine

draw life cycle of a pine

sepals

enclose flower

carpel

female reproductive organs consisting of the stigma, style, and ovary.

Name the reproductive adaptations of Angiosperms

flowers and fruits

Explain how the pine life cycle reflects basic characteristics of seed plants.

heterospory - ovulate cones produce megaspores and pollen cones produce microspores reduced gametophytes as pollen grains and female gametophyte within the megaspore. egg within an ovule and pollen tube is conveying the sperm

filament

in angiosperm, the stalk of a stamen, the pollen-producing reproductive organ of a flower

microspore develops into a pollen grain that consists of a ______________ gametophyte enclosed within the pollen wall. is it male or female?

male

stamen

male reproductive organs consisting of an anther and a filament.

does megasporangia produce megaspores that give rise to male or female gametophytes?

mega - female micro - male

reduced gametophytes

microscopic male and female gametophytes (n) are nourished and protected by the sporophyte (2n) (develop within walls of spores that are retained in tissues of parent sporophyte)

petals

modified leaves which are usually bright in color to attract pollinators.

fruit is formed when the ______ wall thickens and matures

ovary

If a sperm fertilizes the egg of a seed plant, the __________ will develop into a seed

ovule

cross-pollination

pollination of a flower or plant with pollen from another flower or plant.

List 5 derived traits of seed plants

reduced gametophytes heterospory ovules pollen seeds

cotyledon

seed leaf of an angiosperm embryo.

Know the structure of a flower

stamen - anther, filament carpel - stigma, style, ovary sepal ovule petal

a pollen grain that has landed on a ________ germinates, and the pollen tube of the __________ gametophyte grows down to the ovary

stigma male