Biology Ch.27 Adaptations of Plants to Life on Land
Plants four major groups:
bryophytes, seedless vascular plants, and two groups of seeded vascular plants, the gymnosperms and angiosperms
____ consist of about 16,000 species of mosses, liverworts, and hornworts
byrophytes
Structural and molecular data indicate that land plants probably descended from a group of green algae called....
charophytes or stonewarts
were important plants millions of years ago, when species that are now extinct often reached great size. These contributors to our present day coal deposits
club mosses
The most common names for the phylum Lycopodiophyta are...
club mosses and ground pines
Two main clades of seedless vascular plants
club mosses and the ferns
What does the cuticle prevent?
desiccation, or drying out, of plant tissues by evaporation.
Whenever the stem forks, or branches, it always divides into two equal halves called
dichotomous branching
In plants the fertilized egg develops into a multicellular _________ within a female gametangium.
embryo
sex organs, or ____ of most plants are multicellular,
gametangia
what conducts dissolved organic molecules such as sugar
phloem
what is a common liverwort that is a thalloid?
polymorpha
The mature fern gametophyte, which bears no resemblance to the sporophyte, is a tiny, green, often heart=shaped structures that grows flat against the ground called a
prothallus. the fern gametophyte lacks vascular tissues and has tiny, hairlike absorptive rhizoids to anchor it.
If a moss spore lands in a suitable spot, it germinates and grows into a filament of cells called
protonema
The fern sporophyte consists of a horizontal underground stem called
rhizome, it can bear leaves
What stems do horsetails have?
rhizomes and erect aerial stems
Liverwarts can reproduce....
sexually and asexually
sexual reproduction of liverworts involve
sexually and asexually
Spore production usually occurs in certain areas on the fern fronds. Many species bear the sporangia in clusters called
sori
When two gametes fuse, the diploid portion of the life cycle, called _____ begins. It produces haploid spores by the process of meiosis. - present the first stage in the gametophyte generation
sporophyte
What facilitates gas exchange that dot the surfaces of leaves and stems of almost all plants
stomata
consists of several stalked, umbrella-like structures, each of which bears five to ten sporangia in a circle around a common axis. - it is the reproductive branch of a horsetail
strobilus
In temperate regions ferns commonly inhabit...
swamps, marshes, stream banks, and moist woodlands
Their body form is often a flattened, lobed structure called a
thallus
How many species of whisk ferns exist today?
12
Seedless vascular plants arose and diversified during the Silurian and Devonian periods of the Paleozoic era between
444 mya and 359 mya
One important difference between plants and algae is that a waxy ___ covers the aerial portion of a plant.
Cuticle
what genus is the horsetail in?
Equisetum
are terrestrial, although a few have adapted to aquatic habitats. Range from the tropics to the Arctic Circle, with most species living in tropical forests.
Ferns
what is the main organ of photosynthesis?
Green stem
its a small group of about 100 species of bryophytes whose gametophytes superficially resemble those of the thalloid liverworts
Hornworts
What is considered the most dominant plant?
Horsetails
____ consist of about 6000 species of nonvascular plants with a dominant gametophyte generation, but the gametophytes of some ____ are quite different from those of mosses
Liverworts
less than 25 cm, or 10 in. tall. attractive plants common in temperate woodlands. They possess true roots, both rhizomes and erect aerial stems, and small, scalelike leaves.
Lycopodium
evolved from stem branches that gradually filled in with additional tissue to form most leaves as we know them today
Megaphylls
The ____, which is usually small and has a single vascular strand, probably evolved from small, projecting extensions of stem tissue. Only one group of living plants, the club mosses, has microphylls
Microphyll
____ which include about 9900 species, usually live in dense colonies or beds
Mosses
The moss ____ is a particularly important research organism for studying plant evolution because its features and genome can be compared with those of algae and flowering plants.
Physcomitrella
What is the main organ of photosynthesis on a whisk fern?
Psilotum
Meiosis occurs, forming spores within each ____, or spore case
Sporangium
The most important mosses are the peat mosses in the genus...
Sphagnum
which they spend part of their lives in a multicellular haploid stage and part in a multicellular diploid stage
alternation of generations
The haploid gametophytes produce male gametoangia, known as....
antheridia
red algae, green algae, and land plants are collectively classified as..
archaeplastids
Gametophytes also produce female gametangia, known as
archegonia
In some liverworts these gametangia are borne on stalked structures called
archegoniophores
haploid portion of the life cycle is the ____ because it gives rise to haploid gametes by mitosis.
gametophyte generation
Some liverworts reproduce asexually by forming tiny balls of tissue called:
gemmae
A unique feature of hornworts is that the sporophytes unlike those of mosses and liverworts, continue to grow from their bases for the remainder of the gametophyte's life. This is called
indeterminate growth
a strengthening polymer in the walls of cells that function for support and conduction
lignin
What group do all plants come from?
monophyletic group
conducting dissolved organic molecules such as sugar
xylem
What are the two vascular tissues?
xylem and phloem
Sperm cell fertilizes the egg to form a ___ or fertilized egg
zygote