Introduction to Plants

The Plant Kingdom

Photosynthesis and Light

Mosses, Liverworts, and Hornworts

Ferns, Club Mosses, and Horsetails

Table of Contents


What Is a Plant?Nearly all plants are autotrophs-produce their own food.

All plants are eukaryotes

contain many cells

all plant cells are surrounded by cell walls.

- The Plant Kingdom


Adaptations for living on land• Obtaining water and other nutrients

• Retaining water- cuticle/ reduce water loss

• Transporting materials-vascular tissue/ tubelike structures- carry food, water, minerals

• Support

• Reproduction –zygot / fertilized egg


Classifying plants

Nonvascular- don’t have a system of tubes/ low growing, do not have roots

Vascular –have vascular tissue/ tall

Origin of plants- green algae

- The Plant Kingdom


Complex Life CyclesPlants have complex life cycles that include two different stages:

Sporophyte- plant produces spores

Gametophyte- plant produces two kinds of sex cells: sperm cell and egg cell.

- The Plant Kingdom


Water Loss in Plants

The graph shows how much water a certain plant loses during the hours shown.

- The Plant Kingdom



Horizontal axis–time of day; vertical axis–water loss.

Reading Graphs:

What variable is plotted along each axis?

- The Plant Kingdom



Most–midday; least–in the evening.

Interpreting Data:

According to the graph, during what part of the day did the plant lose the most water? The least water?

- The Plant Kingdom



The plant seemed to lose the most water during the sunniest or warmest parts of the day.

Drawing Conclusions:

What could account for the pattern of water loss shown?

- The Plant Kingdom



The line graph would descend during the night and then rise again in the morning hours, because the water loss is less during the night when there is no sun.

Predicting:

How would you expect the graph to look from 10 p.m. to 8 a.m.? Explain your reasoning.

- The Plant Kingdom


A definition states the meaning of a word or phrase by telling about its most important feature or function. After you read the section, reread the paragraphs that contain definitions of Key Terms. Use all the information you have learned to write a definition of each Key Term in your own words.

- The Plant Kingdom

Key Terms: Examples:photosynthesis Sunlight provides the energy for this food-making

process, called photosynthesis.

tissue No matter how large or small a plant is, its cells are organized into tissues—groups of similar cells that perform a specific function in an organism.

chloroplast Chloroplasts, which look something like green jelly beans, are the structures in which food is made.

vacuole A vacuole is a large storage sac that can expand and shrink like a balloon.

Key Terms: Examples:cuticle

vascular tissue

fertilization

zygote

One adaptation that helps a plant reduce water loss is a waxy, waterproof layer called the cuticle, which covers the leaves of most plants.

Vascular tissue is a system of tubelike structures inside a plant through which water, minerals, andfood move.Fertilization occurs when a sperm cell unites with an egg cell.

A fertilized egg is called a zygote.

Key Terms: Examples:nonvascular plant

vascular plant

chlorophyll

Plants that lack a well-developed system of tubes for transporting water and other materials are known as nonvascular plants.

Plants with true vascular tissue are called vascular plants.

Biologists studied a green pigment called chlorophyll, found in the chloroplasts of plants, algae, and some bacteria.

Key Terms: Examples:sporophyte

gametophyte

In the sporophyte stage, the plant produces spores, tiny cells that can grow into new organisms.

In the gametophyte stage, the plant produces two kinds of sex cells: sperm cells and egg cells.

Building Vocabulary


The Photosynthesis Process• The roots of plants take in

water and nutrients and send it to the leaves.

• Leaves take in carbon dioxide.

• The combination of carbon dioxide and water in the presence of sunlight. Glucose (sugar) is made and the plant gives off oxygen.

- Photosynthesis and Light

Carbon Dioxide + Water oxygen + glucose


Preview Figure 9. Then write three questions that you have about the diagram in a graphic organizer like the one below. As you read, answer your questions.

Q. How is sunlight involved in photosynthesis?

A. The energy in sunlight is used to make sugar.

Q. Why does a plant need sugar?

A. The plant uses energy from the sugar to carry out life functions.

Water Vascular System

Q. How does the plant use the water its roots take in?

A. Water molecules combine with carbon dioxide to form sugar and oxygen during photosynthesis

- Photosynthesis and Light

Previewing Visuals


Main Idea

Detail Detail Detail

Nonvascular plantsLive in moist area

Absorb water and nutrients directly from the environmentThin Cell Walls

include…

Mosses Liverworts Hornworts

- Mosses, Liverworts, and Hornworts

Identifying Main Ideas


Mosses


Mosses

• A moss gametophyte is low-growing and has structures that look like roots, stems, and leaves.

• The sporophyte generation grows out of the gametophyte.

• The rhizoids anchor the moss and absorbs water and nutrients from the soil.

- Plants Without Seeds: Mosses, Liverworts, and Hornworts


Mosses, Liverworts, and HornwortsSphagnum moss grows in a wetland called

bogs.

Peat moss is formed in acidic bogs where dead material does not decay because decomposers can’t live in acidic water.

• The dead material builds up and is compressed into peat, which is used as a fuel.

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Liverworts• More than 8,ooo species• Grow as a thick crust on moist rock or

soil• The body of the liverwort looks like a

human liver.

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Hornworts• Fewer than 100 species• Live in moist soil often mixed with grass

plants• Grow hornlike structures called

sporophytes.


Characteristics Mosses 1. Hornworts

Contain vascular tissue

no 2. No

height 3. Low-growing Low-growing

Size Small Small 4.

Moisture needs 5. Places high in moisture

Places high in moisture

Where they grow Tree trunks or wet rocks

Moist rocks or moist soil

6.

Mosses, Liverworts, and Hornworts


Characteristics of Seedless Vascular PlantsFerns, club mosses, and horsetails share two characteristics:•they have true vascular tissue: a system of tubelike structures inside a plant that water, minerals, and food move through

• they do NOT produce seeds

•Live in moist surroundings so sperm can swim to eggs and reproduce by releasing spores

•grow quite tall because of their strong, vascular tissue transports material throughout the plant and gives it structure.

- Ferns, Club Mosses, and Horsetails


Ferns• Most ferns have underground

stems and to roots. • Fronds- fern leaves that grow

above ground.• The upper surface of the frond is

coated with a cuticle which helps preserve water.

• Spores develop in tiny spore cases on the underside of the frond.

• When spores are released, wind and water carry them great distances.

• The roots anchor the fern to the ground.



Ferns, Club Mosses, a Ferns, Club Mosses, and Horsetails nd Horsetails

Horsetails• Long, coarse, needlelike branches that grow in a circle around a

joint.• Small leaves grow flat against the stem just above each joint. • The stems contain silica, a gritty substance also found in sand.

Club mosses• Only few hundred species• Sometimes called Princess Pine• Grow in moist woodlands or near streams.• Similar to ferns• Have vascular tissue

Other Vascular Plants


Spores on a Fern frond


Question AnswerWhat are the characteristics of seedless vascular plants?

Seedless vascular plants have vascular tissue; they do not produce seeds; they reproduce by releasing spores.

How do ferns reproduce? Ferns reproduce by spores that form on the underside of their fronds.

How do club mosses differ from true mosses?

Club mosses have vascular tissue.

Asking QuestionsBefore you read, preview the red headings. In a graphic organizer like the one below, ask a what, how, or where question for each heading. As you read, write the answers to your questions.

Ferns, Club Mosses, and Horsetails



Graphic Organizer

Small and low

Moist

True roots,stems, and leaves

Gametophyte

Yes

Characteristic Moss Fern

Can be tallSize

MoistEnvironment

Body parts Rootlike, stemlike,leaflike structures

Sporophyte

No

Familiar generation

Is true vasculartissue present?


Vocabulary

Photosynthesis chlorophyll tissue cuticle

vascular tissue fertilization zygote

Sporophyte nonvascular plants peat bog

gametophyte rhizoids fronds

Spores vascular plants


Documents

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