Introduction to Plants Chapter 23 Introduction to Plants Section 1: Adaptations of Plants Section 2: Kinds of Plants Section 3: Plants in Our Lives Plant Structure & function

The Plant Cell- review Are plants autotrophic or heterotrophic? Autotrophic (remember, plants are producers and they make their own food via photosynthesis) Are plants prokaryotic or eukaryotic? Eukaryotic (remember, eukaryotes have nuclei just like we do and YOU are EUkaryotes) Are plants multicellular or unicellular? Multicellular! Plant cell walls are made of…. Cellulose

The Plant Cell: Label!

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 (vascular) and tracheophytes (nonvascular); 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

Adaptations of Plants Establishment of Plants on Land Section 1 Adaptations of Plants Establishment of Plants on Land Absorbing Nutrients To survive on land, plants evolved the ability to absorb mineral nutrients from the soil. Preventing Water Loss To survive on land, plants evolved a waxy outer covering called a cuticle, and stomata and guard cells for gas exchange, to prevent their bodies from drying out. Reproducing on Land To survive on land, plants use pollen to reproduce without water and transmit male gametes. http://en.wikipedia.org/wiki/Image:Devils_Punchbowl_Waterfall%2C_New_Zealand.jpg

Adaptations of Plants Vascular Tissue, Seeds, and Flowers Section 1 Adaptations of Plants Vascular Tissue, Seeds, and Flowers Advantages of Conducting Tissue Vascular plants have a system of well-developed tissues that transport water within a plant. Advantages of Seeds Seeds protect and nourish a plant’s embryo, disperse the offspring, and delay the growth of the embryo until conditions are favorable. Advantages of Flowers Flowers make reproduction more efficient by promoting pollination. http://upload.wikimedia.org/wikipedia/commons/4/46/Diversity_of_plants_image_version_3.png

Adaptations of Plants Plant Life Cycles Section 1 Adaptations of Plants Plant Life Cycles The Vascular-Plant Sporophyte The sporophytes of vascular plants have a vascular system. Their bodies consist of an aboveground shoot and an underground root. http://en.wikipedia.org/wiki/Sporophyte

More Vocabulary Seed- adaptation to terrestrial life composed of a plant embryo, stores food and contains a protective coat Cone- reproductive structure of gymnosperms; contains pollen in males and ovules in females Ovulate cone- from a pinetree (female) Staminate cone- from a pinetree (male) Flower- reproductive structure of angisperms composed of 4 sets of modified leaves Fruit- mature ovary of a flower that protects dormant seeds and aids in their dispersal

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

Kinds of Plants Nonvascular vs. Vascular Nonvascular plants do not have a system for transporting water and other nutrients within their body Vascular plants are plants that contain structures with vascular tissue (roots, stems and leaves) Seedless plants Seed plants Gymnosperms and Angiosperms

Kinds of Plants Nonvascular Plants Section 2 Kinds of Plants Nonvascular Plants Key Features of Nonvascular Plants Nonvascular plants are small and lack vascular tissue (roots, stems and leaves). Kinds of Nonvascular Plants. Mosses, liverworts, and hornworts are nonvascular plants. http://en.wikipedia.org/wiki/Image:Anthoceros_levis.jpg

Bryophytes – nonvascular plants 20 mm Liverworts Hornwort Moss

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

Kinds of Plants Seedless Vascular Plants Section 2 Kinds of Plants Seedless Vascular Plants Key Features of Seedless Vascular Plants Seedless vascular plants produce spores with thickened walls that prevent them from drying out. Kinds of Seedless Vascular Plants Ferns, club mosses, horsetails, and whisk ferns are seedless vascular plants. http://en.wikipedia.org/wiki/Image:Lycopodium_plant.jpg

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 fern

Seedless vascular plants dominated during the Carboniferous period.

Kinds of Plants Gymnosperms Section 2 Kinds of Plants Gymnosperms Key Features of Gymnosperms Gymnosperms are seed plants that produce cones. Kinds of Gymnosperms Conifers, cycads, ginkgoes, and gnetophytes are gymnosperms. http://en.wikipedia.org/wiki/Image:Welwitchia.jpg

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

Welwitschia Gnetum Ephedra 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

Kinds of Plants Angiosperms Section 2 Kinds of Plants Angiosperms Key Features of Angiosperms Angiosperms are seed plants that produce flowers and fruits. Kinds of Angiosperms The angiosperms are classified as either monocots or dicots. http://upload.wikimedia.org/wikipedia/en/7/78/WIKI-Grass.jpg

Monocots vs. Dicots Dicots: Monocots: Two cotyledon One cotyledon Veins netlike Vascular bundles arranged in ring Taproot usually present Floral parts in four or five Ex. Asteraceae (composite), Brassicaceae (mustard), Fabaceae (legume), and Rosaceae (rose), Monocots: One cotyledon Veins parallel Vascular bundles in complex arrangement Fibrous root system Floral parts in multiples of three Ex. Iridaceae (irises), Liliaceae(lilies) and Poaceae (grass).

Subgroups of Angiosperms: Monocots & Dicots

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

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

Flower pistil

Plants in our Lives Plants as Food Section 3 Plants in our Lives Plants as Food Fruits and Vegetables All types of plant parts—roots, stems, leaves, flowers, fruits, and seeds—provide food for humans. Root Crops Root crops, such as potatoes, grow underground. Legumes Legumes, such as peas, produce protein-rich seeds in long pods.

Plants in our Lives Cereals Section 3 Plants in our Lives Cereals Wheat For more than one-third of the world’s population, wheat is the primary source of food. Corn Corn is the most widely cultivated crop in the United States. Rice For more than half of the people in the world, rice is the main part of every meal.

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; http://homecooking.about.com/library/weekly/blflowers.htm Good rule of thumb: if you didn’t get it at the store, DON’T EAT IT!

Plants in our Lives Nonfood Uses of Plants Section 3 Plants in our Lives Nonfood Uses of Plants Wood Wood is a source of wood pulp used for making paper, lumber used for building materials, and fuel. Medicines Many important medicines are currently made from plants or were originally derived from plants. Fibers Plant fibers are used to make paper, cloth, and rope. The most important sources of plant fibers are wood and cotton. http://upload.wikimedia.org/wikipedia/commons/0/0b/Taxus_wood.jpg

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

Plant Structure & Function Chapter 25 Pg. 551 - 564

6H2O + 6CO2 + sunlight 6O2 + C6H12O6 More Review Do you remember the equation for photosynthesis 6H2O + 6CO2 + sunlight 6O2 + C6H12O6 Do you remember what organelle photosynthesis takes place in? The Chloroplast

Plant Structure Plants are composed of: Tissue Roots Leaves Stems Each plant part – tissue, root, stem, leaf - has a specific role in keeping the plant alive through photosynthesis

Structure: Tissues- 3 types Vascular Plant Body A vascular plant’s body contains three kinds of tissues—dermal tissue, ground tissue, and vascular tissue. 1.Dermal Tissue Dermal tissue covers a plant. A thin layer of epidermis covers nonwoody parts. Several layers of cork cover woody parts. 2.Ground Tissue Ground tissue is specialized for photosynthesis in leaves and for storage and support in stems and roots.

Review: Vascular Tissues 3.Vascular Tissues Vascular tissue conducts water, minerals, and organic compounds throughout the plant. Xylem - contains vessels, which are made up of cells that conduct water only after they lose their cytoplasm. Water flows between cells through pits and perforations in their cell walls. Carry reactants Phloem -contains sieve tubes, which are made up of cells that are still living. Substances pass between the cells through pores. Carry products

Plant Structure: Roots Function- absorption, storage and anchorage Roots have a central core of vascular tissue that is surrounded by ground tissue and epidermal tissue. Root hairs on root tips increase the surface area which increases absorption Remember that Nitrogen Fixation happens in the roots! (Nitrogen fixation is when nitrogen in the atmosphere is converted by bacteria into nitrogen compounds like ammonia, nitrates and nitrites)

Plant Structure: Leaves Site of photosynthesis composed of blade, veins, petiole There are different layers of leaves (next slide) simple or compound

Leaves Cross Section - epidermis – adaptation for terrestrial life- covering of leaf - waxy cuticle - coats upper and lower epidermis - stomata – site of transpiration

Movement of Water : Transpiration Transpiration, the loss of water from a plant’s leaves, creates a pull that draws water up through xylem from roots to leaves. Guard Cells and Transpiration Guard cells control water loss by closing a plant’s stomata when water is scarce. Thus, they also regulate the rate of transpiration.

Movement of Organic Compounds Translocation Organic compounds are pushed through the phloem from a source to a sink in a process called translocation.

See pg. 559 – Yes, you need to know the layers of leaves

Plant structure: Stems Function: support and transfer Contain the Xylem and Phloem Help define plant types (shrubs, vines, trees, etc)

Plant Structure and Function Chapter 25 Plant Structure and Function Leaves lose water by transpiration. Leaves produce sugars in photosynthesis. Sugars are transported downward in the stem. Sugars are transported into flowers and fruits. Sugars are transported upward to leaf buds in the spring. Water enters the xylem of roots and moves upward into the xylem of the stem. Sugars are transported downward into roots for use or storage.

Overview of plants and photosynthesis happenings