Classifying Plant Groups 4.1

Organization Plants Vascular Nonvascular Seedless Seed Angiosperms Gymnosperms Ferns and related plants Mosses and related plants

Learning Targets I can understand plants are classified according to similar structures I can explain the difference between vascular and nonvascular plants I can compare and contrast seed plants and seedless plants I can define angiosperm, gymnosperm, dicot and monocot

How are plants Classified? Scientists have discovered over 300,000 different kinds of plants About 1,000,000 plants may exist that have not been found and named Scientists believe these plants live in the tropical rain forest

Classification Plants are classified according to whether they have body parts such as seeds, tubes, roots, stems, and leaves There are 3 main groups of plants: Seed Plants Ferns Mosses

History of Classification The Greek philosopher Aristotle first classified plants and animals Carl Linnaeus then developed a classification system still in use today All living things have a scientific name which consists of the genus and species

Vascular Plants Vascular means “vessel” or “tube” Vascular plants have tube-like cells Seed plants and ferns are examples of vascular plants

Vascular (cont.) These tube-like cells form tissue called vascular tissue The tissue forms tubes that transport food and water through the plant Vascular plants have well-developed leave, stems, and roots

Vascular Tissue This tissue is important in two ways: First, it allows food and water to be transported over a distance Plants can grow where water is not always present Second, vascular tissue is thick and provides support for the plant This allows the plant to grow taller

Nonvascular Plants Nonvascular plants do not have tube-like cells These plants are short and must have constant contact with water They do not have tubes to transport water or support them They do not have true leaves, stems, or roots Mosses are nonvascular plants

Vocabulary Vascular Plant Nonvascular Plant Self Check Questions, pg. 69 #1-5 COMPLETE SENTENCES

What are Seed Plants? 4.2

What are Seed Plants? Seed plants use seeds to reproduce A seed is a plant part that contains a beginning plant and stored food The beginning plant part is called an embryo Seeds have a seed coat, which holds in moisture

Seed Plants (cont.) When conditions are right, the embryo grows into a full-sized plant Seed plants are the largest group of plants They are divided into 2 sub groups: flowering and nonflowering plants

Angiosperms (Flowering) Most species of plants are angiosperms A capsule, or fruit, protects the seeds of angiosperms The fruit forms from part of the flower Angiosperms are divided into two groups: Dicots Monocots

Dicots Have 2 seed leaves (on the embryo) Crisscross pattern of veins on leaves Most flowering plants are dicots Examples: fruits, vegetables, rose, sunflower

Monocots Have only one seed leaf Parallel pattern of veins on leaves Mostly grasses, but some flowers Examples: grass, corn, wheat, rice, lily, orchid

Gymnosperms (Nonflowering) Do not produce flowers Seeds are not surrounded by a fruit Seeds are produced inside cones Example: seeds of pine trees form on the scales of cones

Conifers The major group of gymnosperms Cone-bearing plants Woody shrubs or trees Main source of paper and wood products Examples: pine, spruce, fir

Conifers (cont.) Most have green leaves all year long They are called evergreens Leaves are shaped like needles Makes it easier to live in dry places and store water Grow in places where other plants cannot grow (shallow, rocky soil and along coast)

Vocabulary Angiosperm Gymnosperm Embryo Conifer Seed Monocot Dicot Self Check Questions, pg. 73 #1-5 COMPLETE SENTENCES

What are Seedless Plants? 4.3

Ferns (Vascular) Largest group of seedless plants Well-developed leaves, stem, and roots Mostly tropical plants Leaves are called fronds (large and flat) Fronds uncurl as they grow Sori are clusters of reproductive cells(spores)found on the underside of fronds

Spores Spores are the reproductive cells of ferns and mosses After they are released, spores must land in a moist place or they will dry out Spores that drop in a moist place will have produce a tiny plant The plant must have constant moisture to grow

Spores vs. Seeds Spores must have moist landing and constant water source Seeds have a seed coat to constantly deliver food and water Seeds can survive longer than spores in dry conditions, which is why there are more seed plants in the world

Mosses (Non-Vascular) Reproduce by spores Simple leaf-like and stem-like parts No vascular tissue to transport water and food, so they must live in moist, shady area (wet soil) Have root-like threads called rhizoids Mosses look like little trees and often form carpet-like mats on the forest floor

Vocabulary Frond Sori Spore Rhizoid Self Check questions pg. 78 COMPLETE SENTENCES