Plant Cell Plants are: Eukaryotic Autotrophic Multicellular Cell walls of cellulose

Vocabulary: - vascular – refers to an internal system of tubes or vessels to transport materials throughout the plant; basis or first major division of plants into bryophytes and tracheophytes; includes: - xylem – transports water and minerals up from the roots to the shoots - phloem – transports sugar (food) down from the leaves to the rest of the plant

Xylem brings water up from the roots to the shoots

Phloem carries sugar (food) down from leaves throughout the plant

Bryophytes – nonvascular plants Examples include: MossHornwort Liverworts 20 mm

Bryophytes – nonvascular plants - economically important Ex) sphagnum moss – also called peat or peat moss Grows in boggy areas called peat bogs; extremely absorbant; used in agriculture/horticulture

Vocabulary Seed – adaptation to terrestrial life composed of a plant embryo, stored food, and a protective coat Seed dispersal by edible fruit, by wind, as well as other means. The picture to the right is of a samara from a maple tree. Which is a monocot and which is a dicot? How do you know?

Tracheophytes – vascular plants Seedless plants –whiskferns, horsetails, and ferns Whisk fern horsetail fern

Seedless vascular plants: Ferns - reproduce with spores - diagram shows spores growing in clusters called sori on the back of the frond of the fern

Seedless vascular plants dominated during the Carboniferous period.

Vocabulary Cone – reproductive structure of gymnosperms; contains pollen in males and ovules in females Flower – reproductive structure of angiosperms composed of 4 sets of modified leaves Fruit – mature ovary of a flower that protects dormant seeds and aids in their dispersal

Ovulate cone from a pinetree (female) Staminate cone from a pinetree (male)

Tracheophytes – vascular plants cont. Seed plants Gymnosperms – have seeds in cones; include: ginkgos, cycads, gnetophytes, and conifers Ginkgo Cycad

Welwitschia GnetumEphedra Gymnosperms called gnetophytes; only 3 extant species

Conifers: top row: Douglas fir, Sequoia, Cypress; bottom row: juniper, Australian pine tree; not shown: yew, spruce, other pines

Tracheophytes – vascular plants cont * Seed plants Angiosperms – flowering plants - have flowers, fruits, and seeds

Grasses are flowering plants, too. So are trees. Grass flowers

Flower pistil (female) (male) lily/star.html

Ovaries with ovules become fruits with seeds after the ovule (egg) is fertilized by sperm from the pollen

Pollen grains contain sperm. They are produced in the anthers of the flowers in angiosperms.

Pollination - by many vectors, including: Wind Water Animals

Fruit or Veggie Humans eat lots of different plant parts. A fruit is the ripened ovary and contains seeds. Therefore, tomatoes, peppers, squash, olives, and cucumbers are fruits, not vegetables.

Vegetables – the vegetative parts of the plants that we eat. Includes: Roots – carrots, turnips,radishes Stems – celery, bok choi, rhubarb, garlic, broccoli, onions, potatoes Leaves – lettuce, cabbage, parsley Other plant parts that we eat: Seeds – pinto beans, peas, sunflower seeds, corn, pepper corns, rice, pecans, coconut Flowers – anise flowers (licorice), basil; Good rule of thumb: if you didn’t get it at the store, DON’T EAT IT!

We don’t just eat plants, we also wear them, build with them, and use them for medicines!

Plant Structure & Function

Each plant part - root, stem, leaf - has a specific role in keeping the plant alive through photosynthesis

Each plant part - root, stem, leaf - has a specific role in keeping the plant alive through photosynthesis. Write the equation for photosynthesis: 6 CO H 2 O sunlight  C 6 H 12 O O 2 Carbon dioxide + water in the presence of sunlight yields glucose + oxygen Remember, this takes place in the chloroplasts inside the plant cells.

Monocots & Dicots

Cotyledons – nonphotosynthetic leaves of an immature plant; provide source of nutrients until plant can produce its own food

Leaves - site of photosynthesis - cross section - epidermis – adaptation for terrestrial life - waxy cuticle - stomata - transpiration

Leaf

Leaf structure supports its function as the primary organ for photosynthesis

Leaves - composed of blade, veins, petiole - simple or compound (see identifying leaves ppt) - pinnately or palmately compound - alternate or opposite if compound - pinnate or palmate venation

Overview of movement of photosynthesis reactants and products through a plant

Stems Support and transport Contains xylem and phloem Modified: Strawberry runners onion potatoes

Define plant type: herbaceous, shrub, vine, tree Stems Herbaceous plant shrub vine

Stems – cross sections through a dicot and a monocot

Roots Function – absorption, storage, anchorage Root hairs – extensions of the epidermis that increase absorption by increasing surface area; see photo Fibrous roots – see monocot information Tap roots – see dicot information

Root Structure

Nitrogen fixation – occurs in the roots and in the soil around the roots of plants; performed by bacteria

Plants that live in nitrogen poor soils trap and break down insects with enzymes to obtain nitrogen Venus fly trap Pitcher plant

Vocabulary Primary growth – increase in length; stems get longer, roots grow deeper Meristem – tissue that is growing Apical meristem – tissue found at the tips of roots and stems that is actively dividing/growing

Plant Responses Plant responses are called tropisms. Tropisms can be positive or negative. They include phototropism, gravitropism, and thigmotropism. Most plant responses involve the action of hormones, including gibberellins, auxins, and ethylene.

Plant Responses Effect of gibberellens on Thompson’s seedless grapes and on growth in a dwarf plant

Auxins make plants bushier by making more branches at nodes when the apical meristem is cut off (the tips of the existing branches)

Positive Phototropism opism/phototropism/corn/cornworship.html ism/solartrack/solartrack.html

Effect of ethylene on the ripening of an apple.

on/movements/tropism/gravitropism/gravi1/gravi trop.html NEGATIVE Gravitropism in Stems POSITIVE Gravitropism in roots ments/tropism/gravitropism/rootgrav/graviroot.html

Vines Illustrate Positive Thigmotropism