Gymnosperms and Angiosperms Vascular, Seed Plants Gymnosperms and Angiosperms

Seed Plants Do not require water for reproduction because of pollination, so can live almost anywhere Seed – protective part of plant that contains a plant embryo (baby) and stored food Most plants are seed plants

Gymnosperms Most have their seeds in cones --- conifers (“cone-bearing”) Most keep their leaves all year (evergreens)

Coniferophyta—Conifers Cone—cluster of sporophylls Examples: pine, firs, spruces, junipers, cedars Most evergreen, leaves needle-like Methuselah—bristlecone pine…4600+ yrs. old!

Conifers General Sherman (left)…CA Mtns…trunk circumference is 26m! Redwoods…tip of northern CA…can grow to 110m+ tall! (right)

Conifers….. Roots and stems are hard and woody. Wood is a plant material made mostly of xylem. Conifers are a source of wood, cardboard, turpentine, disinfectants and fuel. They provide food and shelter to many animals.

Life Cycle of a Gymno-sperm

Life Cycle of a Pine Tree Produce male and female cones Male cones produce pollen (sperm) Wind carries pollen to larger female cones The sperm cells fertilize the eggs in the female cones. Seeds, containing the embryo, form between the woody scales of the cone

Anthophyta—Angiosperms flowering plants 250,000 species

Food supply Food supply

Angiosperms… Produce seeds inside a flower Flowers have male (produce pollen)and female parts (produce eggs) Pollen is carried to the egg by wind, insects, or other animals. 2 classes: monocots and dicots

Monocots One seed leaf—cotyledons Examples: lilies, orchids, grasses, grain crops

Dicots 2 cotyledons Examples: roses, peas, sunflowers, oaks, maples

Dicot vs. Monocot Roots Have one main long root (taproot) and branch roots. Have all roots about the same length and none very long. Dicots Tap Root System Fibrous Root System Monocots

Leaves Dicot leaves have branching (net-like) veins Monocot leaves have parallel veins Leaves

Flowers

Stems Vascular tissue organized in a ring Vascular tissue scattered in stem

Roots Vascular tissues Dicot Root Monocot Root

Deciduous Trees Trees that lose their leaves in the Fall.

Evergreens never lose their leaves. Most are conifers.

Annuals—1 year Biennials—2 years Perennials—many years

Typical Flower

Parts of a Flower Stamens: The male part, composed of filament and anther. Releases pollen. Pistil: The female part, composed of style, stigma, and ovule. Petals: The colorful parts. Sepals: Leaf-like parts around petals.

Anatomy of a Flower

Another typical flower

Transpiration Transpiration is the loss of water from the stomata --- like plant sweat. Water enters through the roots. As water is lost from the stomata, water is draw up the step by capillary action and the cohesion of water molecules caused by hydrogen bonding moves the water up the stem.

Is a plant response directed toward light Plant stems growing toward the light source and leaves facing the light. Is a plant response directed toward light Phototropism All sunflowers facing the same way

hormone hormone hormone

Is a plant response directed toward gravity Gravitropism in stems Is a plant response directed toward gravity Gravitropism Gravitropism in roots