Kingdom PlantaeKingdom Plantae

Botany = study of plantsBotanists = plant biologists

Evolution of Terrestrial PlantsEvolution of Terrestrial Plants

• As plants began to survive on land, they altered the conditions by slowly creating soil and microclimates.

• Plants provided food for animals that were also evolving systems to cope with terrestrial life.

Examine your flowerExamine your flower

• Record observations about how plants have evolved to survive on land.

Plant ModificationsPlant Modifications

• Supportive structures—stems and roots/rhizoids (hair like roots found in mosses and ferns)

• Transport systems —vascular system (xylem carries water and materials up from roots, and phloem transports sugar down from the leaves)

Plant ModificationsPlant Modifications

• Reduce water loss—cuticle (made of wax)

• Regulate gas exchange & reduce water loss—stomata

• Reproductive strategies—spores, pollen, nectar, and seeds

CharacteristicsCharacteristics• Lack mobility

• Their cells are eukaryotic

• Have numerous organelles

• Have cell walls that contain cellulose

• Have the ability to synthesize carbohydrates through the process of photosynthesis

Divisions of the KingdomDivisions of the Kingdom

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Bryophytes

Non-Vascular Plants- Bryophytes• Mosses form the largest and most familiar group of bryophytes

• Found in moist environments

• They lack a vascular system (no xylem or phloem)

• Mosses depend on simple diffusion, osmosis, and active transport to move nutrients, wastes, and water to and from their cells.

Bryophytes

• They are often the first to establish themselves on exposed rock or soil surfaces where there are no other plants

•As the moss plants die and decompose, they create organic matter to act as soil and nutrients for other types of plants

•There are at least 1170 species of mosses in North America alone

Examining MossExamining Moss

• Pg 384

AnswersAnswers

• (a) Mosses obtain water from the environment through osmosis.

• (b) Peat moss increases the water-holding capacity of garden soil.

• (c) One problem associated with using too much peat moss in garden soil is that many plants cannot live in an environment with too much water. Also, mosses become acidic as they decompose.

• (d) Bogs, composed of peat moss, are responsible for a variety of ecologically beneficial actions. Bogs filter and collect water, accumulate carbon, and provide a habitat for flora and fauna. Peat moss is economically beneficial as a commercial garden product, but is also a renewable source of energy.

Vascular vs Non Vascular Vascular vs Non Vascular

• Colored water with flower vs moss.

• What will happen?

Vascular Plants- SeedlessVascular Plants- Seedless• Ferns are of the phylum tracheophyte. They are plants with a

vascular system (have xylem and phloem)

• The leafy portion of the fern is called the frond.

• The stems are called rhizomes

• Ferns do not have flowers or seeds. They reproduce as spores like mosses.

FernsFerns

Microscope activity

Reproductive Cycle Terms Reproductive Cycle Terms • Alternation of Generations- The complete life cycle of a plant

• Gametophyte- Stage in which cells have haploid nuclei. Begins with haploid spores. In ferns the gametophyte plant is called a prothallus.

• Sporophyte-Stage in which cells have diploid nuclei. Arises from union of 2 haploid gametes.

• Sporangium- Cell structure in which spores are produced asexually (in mosses, fungi and ferns)

Alternation of Generations - Alternation of Generations - FernFern

Vascular Plants- Seeds- GymnospermsVascular Plants- Seeds- Gymnosperms

• Gymnosperms are plants that produce “naked” seeds (not enclosed in a fruit), usually inside cones

• Examples include pine trees and spruce trees

• Most have evolved needlelike leaves, which help the plants resist hot, dry summers, cold winters, and moderate rainfall.

• The needles are covered by a hard, waxy cuticle, which helps the plant retain moisture.

GymnospermsGymnosperms

• Gymnosperms have roots that extend over a wide surface area, rather than penetrating deep into the soil.

• These roots anchor the tree even in locations where soil is scarce.

Vascular Plants- Seeds- AngiospermsVascular Plants- Seeds- Angiosperms• Angiosperms are plants that produce seeds enclosed in fruit

formed by certain flower parts

• There are over 250 000 known species of angiosperms (more species of plants than in all the other plant divisions combined)

• Angiosperms are flowering plants that come in all shapes, sizes, color, etc….

• No other division of plants has flowers. The flower is the reproductive centre of the plant.

Perfect and Imperfect FlowersPerfect and Imperfect Flowers

• Angiosperm that have both male and female reproductive organs on the same flower is called a perfect flower (wood lily).

• Angiosperms that have separate male and female flowers are called imperfect flowers (some pumpkin species).

Flower PartsFlower Parts• Stamen- male part of the flower that consists of a thin stalk called

the filament, and an anther, in which pollen grains are formed

• Pistil- female part of the flower that consists of three main parts: stigma, style, and ovary.

• Carpel- One subunit of a more complex ovary

• Sepals- Small, green, leaf like structures that enclose the developing flower.

• Petals- Often large and colorful

Flower PartsFlower PartsHand out blank flower

Flower Dissections Flower Dissections

On Cue CardsOn Cue Cards

• Write down all of the flower parts you remember.

• Include their functions if you can.

Monocots and DicotsMonocots and Dicots• Angiosperms are grouped into two classes: monocots, which

have one cotyledon, and dicots, which have two cotyledons

• A cotyledon is a seed leaf that stores carbohydrates for the young plant and often becomes the first leaf to appear as the seed germinates.

• Monocot example: Corn

• Dicot (more common) example: Beans

Monocots and DicotsMonocots and Dicots

Flower DemoFlower Demo

Alternation of Generations- Male PartsAlternation of Generations- Male Parts• The filament gets longer and the anther enlarges

• Each anther has chambers in which diploid microspores are located.

• Each of these undergoes meiosis to form haploid microspores

• Each will develop into a mature pollen grain and the anther chambers split

• The pollen grains will coat the outside of the anthers.

Alternation of Generations- Female partsAlternation of Generations- Female parts

• The style gets longer and the stigma enlarges and secretes a sticky, scented, substance that covers its surface.

• At the bottom of the pistil, the ovary also enlarges.

• Within each ovule, a diploid megaspore undergoes meiosis and

forms four haploid megaspores. Only one survives as the egg.

Alternation of Generations Alternation of Generations • Pollination is usually carried out by wind or insects

• The transfer of pollen from the anther to the stigma on the same plant is called self-pollination

• When pollen is transferred to a flower on a different plant, it is

called cross-pollination

• The pollen grains stick to the stigma. Part of the pollen makes

its way down through the style (via pollen tube) and reaches the egg in the ovule

Alternation of Generations Alternation of Generations • Fertilization the fusion of microspore and megaspore nuclei

produces the diploid zygote.

AnimationAnimation

Explain Everything Explain Everything

• Nature walk

• Take photos

• Try to find a plant from each plant division

• Make explain everything presentation