Download HM6 Science Unit A Chapter 1 Lesson 2 Outline - Spring

Name: ___________________________________________________________________________________________
Unit A: Continuity of Life
Chapter 1:
Classification of Living Things
Lesson 2 – Part 1:
How are Plants Classified?
II. Classifying Plants
A. Main Idea: All plants are ________________________. Almost all make their
own ___________ using the Sun’s energy. Plants are classified according to the
ways ______________________________ and ___________________________.
B.
The Plant Kingdom
1. Plants are in the domain __________________________.
a. They are __________________________life forms.
b. This means that they have __________________________in their cells.
2. Plants are __________________________.
a. Plants have differentiated tissues and organs.
b. This means they have specialized parts for certain life functions (like you
do—but plant tissues and organs are very different from yours!).
3. The cells of plants have __________________________.
a. Plant cells are different from animal cells in that they have these walls.
b. The cell walls are made of cellulose; it makes the walls stiff (and hard to
digest when eaten).
4. The cells of plants have __________________________, which are the specific
structures in a plant cell that allows them to use the Sun’s energy to make their
own food in the process known as __________________________.
Name: ___________________________________________________________________________________________
a. Recall that several other life forms that are not plants—or even in the same
domain as plants—also can perform photosynthesis.
b. Some examples of life forms that are not plants that can also perform
photosynthesis include certain bacteria or archaea.
5. Many plants live on __________________________ and do not need to be
submerged in water like certain other photosynthesizing life (such as algae).
6. The Plant kingdom can be divided into _______ main categories:
a. ____________________________________
1) These plants must soak up water ______________ the use of roots.
a) Instead of roots, bryophytes have rhizoids.
b) Unlike the roots in plants, rhizoids do not absorb water or nutrients.
c) Their main function is to attach the plant to its substrate.
2) They need to be in a damp environment or close to a body of water.
3) Bryophytes reproduce by producing special structures call sporophytes; the
spores are usually eventually dispersed by water.
4) Examples of bryophytes include:
a) ____________________
1) Mosses have an erect shoot bearing tiny leaflike structures arranged
in spirals.
2) These are small, fairly simple, plants usually found in moist locations.
moss will cover moist, shady ground other substrates
moss usually is comprised of tiny, spiraled leaves
Name: ___________________________________________________________________________________________
b) ____________________
1) Liverworts have a thin, leathery body that grows flat on moist soil.
2) In some cases, liverworts will grow on the surface of still water.
3) In appearance they can look leaf-like (leafy liverworts) or form large
flat sheets (thallose liverworts).
a) Thallose liverworts are quite distinctive and are easily recognized.
b) The leafy ones are easily mistaken for mosses; it can take careful
examination to tell the difference.
The photo (courtesy of William C. Steere and AIBS Bulletin) is of a
common liverwort, Ricciocarpus natans.
A liverwort thallus.
c) ____________________
1) Hornworts have a roseate or ribbon-like body, or thallus.
2) They differ from liverworts in that they produce stem-like, hornshaped structures that grow upwards from the thallus which will
eventually split at the ends to release spores.
Hornworts grow flat across a substrate but eventually produce stalk-like extensions for the purpose of producing
and spreading spores into the environment.
Name: ___________________________________________________________________________________________
b. ____________________________________
1) These plants have a specialized system of tube-like tissues that can
__________________________, and often other (food) substances,
around the tree as needed.
2) __________________________are a feature of these kinds of plants.
3) A vascular system provides support and allows some of these types of
plants to grow __________________________.
4) __________ plants are vascular.
5) Tracheophytes can further be divided into two subcategories:
a) __________________________ (spore-bearing)
b) __________________________
C. Ferns
1. Ferns are __________________________plants.
a. Ferns have the following physical features:
1) Fronds (like leaves)
2) Rhizomes (like stems)
3) Roots
4) Sporangia (reproductive structure, usually found under the fronds)
2. Ferns ______________________________, unlike most vascular plants.
3. Instead, similar to fungi, they use ______________ to reproduce.
Name: ___________________________________________________________________________________________
D. Gymnosperms
1. Gymnosperms are __________________________plants.
2. They generate _________________.
a. Seeds contain plant embryos (the beginning of a new plant), and provide
__________________________and a __________________________for t
that embryonic plant.
b. The seeds of gymnosperms are often described as “naked seeds” because
they lack the protective ovary, or fruit, generated by angiosperms.
c. The seeds are usually found in structures called ________________, but
sometimes they end up within __________________________.
3. These plants do not create ____________________or _______________.
4. Gymnosperms all produce strobili (“stro-bye-lie” – singular is strobilus
“stro-bye-luss”) for reproduction.
a. Strobili are what most people call “cones”—think pine cones here.
b. There are separate male and female strobili
1) Male strobili produce tiny pollen grains and release them into the air.
2) Female strobili produce ovules (eggs) and catch the pollen, usually aided
by the use of sticky “pollination drops” exuded from the female cone
which recede into the cone carrying pollen grains to the egg cells within.
c. Some strobili are very different in appearance from others.
1) Some can be much smaller or much larger than a common pine cone.
2) A small number of species produce female cones with a small, berry-like
structure (the conifers yew and juniper, for example) or a fruit-like
seedcoat (Ginkgo biloba).
d. Rarely, some species (the gnetophytes Ephedra foeminea and Welwitschia
mirabilis) will exude pollination drops on both the male and female cones in
order to encourage insect-born pollination between male and female strobili
(similar to an angiosperm/bee pollination relationship).
5. Gymnosperms are divided into 4 main groups:
______________, _______________, _______________, & _______________
Name: ___________________________________________________________________________________________
a. Conifers
1) Conifers are called this because they very obviously generate _________.
2) A great example of a conifer is a _________________________, known
for generating __________________________ (“male” and “female”
cones are produced by the same plant).
a) A mature female pine cone is woody; early on, they are scaly, green
and far less brittle.
b) Eventually, they turn woody, separate, and the seeds drop off.
c) It takes two years for a cone to develop to maturity; you often can find
pine cones of different stages of development on the same tree.
Male strobili (cones) just before pollen release.
Female strobili (cones) of pine: The one on the left
(which would be green) is a young cone a year
after pollination, the right a mature cone that has
opened and released the seeds.
d) Pine trees and similar plants are _______________________, meaning
their leaves stay on and green all year round.
e) Trees like this have __________________________leaves.
f) They are an important resource; _____________ and related products
are often made from this type of tree.
g) Conifers cover a huge portion of the northern hemisphere across
several continents.
3) Some of the oldest and largest living things on Earth are conifers.
a) A single Norway spruce in Sweden is the oldest known living thing.
1) The visible portion of this 13-foot-tall "Christmas tree" isn’t actually
that ancient (maybe 600 years)—the above ground trunks get old
and die, but then a clone grows in its place from the same root.
2) This tree’s root system has been radiocarbon dated as having been
growing for the last 9,550 years!
Name: ___________________________________________________________________________________________
b) Bristlecone pines in the western United States are generally
recognized as the world's oldest continuously standing trees, though,
living for about 5,000 years.
c) The largest trees are the giant sequoias (Sequoiadendron
giganteum) of the Sierra Nevada Mountains of California, reaching
heights of more than 312 feet and weights of at least 4.4 million
pounds (compared with 418,878 pounds for the largest recorded blue
whale—but recall that the largest living thing is actually a fungus in
Oregon that is over 3 miles across).
b. Cycads
1) Cycads are an ancient group of seed plants with a crown of large,
compound leaves and a thick trunk.
2) Cycads ____________________________________________________.
3) Unlike palm trees, cycad also ___________________________like all
gymnosperms.
4) Today, only a handful of cycads still exist.
a) Many are facing possible extinction in the wild.
b) However, because of their large attractive leaves, many cycads have
found homes in public and private gardens around the world.
Typical cycad – the King Saga Palm (note: not a palm).
Cycad cones – Sago Palm female cones.
Name: ___________________________________________________________________________________________
c. The Ginkgo biloba tree (“gin-ko bye-loba”)
1) There is only one species of Ginkgo tree still living today, the
__________________________, or maidenhair tree.
2) Ginkgo trees are large trees, normally reaching a height of 66–115 ft.; some
specimens in China are over 160 ft.
3) The deeply fissured, brown bark may appear cork-like in older trees.
4) Its greenish-yellow leaves are fan-shaped and composed of two or more
distinct lobes; the Latin species name biloba refers to this fact.
5) The common name of maidenhair tree pertains to the similarity of the
leaves to those of maidenhair ferns (Adiantum species).
6) This plant is deciduous; in autumn, the leaves of Ginkgo biloba turn a
golden color many find to be rather pretty before falling to the ground.
7) It takes 20-35 years for Ginkgo trees to reach maturity and start bearing seeds!
a) Male and female trees are separate plants.
1) Male trees have pollen-producing strobili.
2) Female trees, once fertilized, bear rounded, yellowish seeds with a
fleshy outer coat resembling a plum.
b) These seeds fall to the ground in the autumn.
c) As the seed coat decays it exudes a rancid smell.
8) The Ginkgo is a very hardy species, often planted in inner city areas
because it has no problem with smog or other types of pollution.
A large Ginkgo tree.
The distinctive bi-lobed leaves of the Ginkgo.
Name: ___________________________________________________________________________________________
d. Gnetophytes
1) There are three living kinds of gnetophytes:
Ephedra, Gnetum, and Welwitschia
a) Most species of Ephedra are branched shrubs (or rarely small trees) while
others are vine-like.
b) Most of the Gnetum are woody vines that climb high into trees of tropical
rain forests in central Africa, Asia, northern South America, and islands
between Australia and Asia, though some species are trees that can grow to
be about 25 ft. tall.
2) The most unusual and geographically restricted gnetophyte is Welwitschia
mirabilis, which is unlike any other plant in the world.
a) This plant was named after Friedrich Welwitsch, an Austrian naturalist who
explored Africa in the 1800's.
b) It is native to a strip of land only 50 miles wide and over 500 miles in length
along the coast of the Namib Desert, which gets less than one inch of
rainfall per year but also gets a regular fog, adding maybe another two
inches of precipitation.
c) These plants are slow growing and can live from 1500 to 2000 years.
d) They form male and female cones on separate plants.
e) They produce only two true leaves in their lifetime, and those leaves
continually grow from the base—all the while, weathering, drying out and
dying off at the tips.
f) There is a taproot that may extend downward deeply before it divides into
numerous thin roots, which must tap a supply of water not available to
other plants of the desert.
Left:
Mature
Welwitschia
next to man
for size
comparison.
Top right:
Male
Welsitschia
cones.
Bottom right:
Female
Welwitschia
cones.
Material in this outline modified from material found at: http://www.ucmp.berkeley.edu/plants/anthocerotophyta.html,
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/M/Mosses.html, http://hiddenforest.co.nz/bryophytes/liverworts/intro.htm,
http://www.bio.miami.edu/dana/dox/altgen_homology.html, http://www.ohio.edu/people/braselto/readings/gymnosperms.html,
http://news.nationalgeographic.com/news/2008/04/080414-oldest-tree.html, http://www.kew.org/science-conservation/plants-fungi/ginkgo-biloba,
http://www.lithops.net/welwitschia_mirabilis_detail.htm, http://www.lithops.net/welwitschia_mirabilis_detail.htm