Revised Plant Science Module

Plant Science: 

Plant Science

Classification of Plants: 

Classification of Plants Long ago, everything living was separated into two categories: animal or plant. Zoology (study of animals) and Botany (study of plants) was born. As knowledge grew in both fields, the classification system became inadequate. There are now six kingdoms into which living matter is divided.

Six Kingdom System: 

Six Kingdom System Eubacteria-- organisms that lack nuclei or other membrane-bound organelles Archaebacteria-- organisms that lack nuclei or other membrane-bound organelles Protista-- an artificial catch-all with intergrading forms and difficult organisms. Most are aquatic and are fundamentally unicellular. Eubacteria Protista

Six Kingdoms: 

Six Kingdoms Fungi--Fungi are many-celled organisms that decompose dead matter in our environment. Plantae--many-celled organisms that are characterized by their tough cell walls and photosynthetic abilities. Animalia--very diverse and very large, numbering over one million identified species. Some are vertebrates(backbone), while most (97%) are invertebrates(no backbone).

Further Classification: 

Further Classification Each of the kingdoms are organized into more specific groups until the species category is reached, which has just one organism.

Example of how a Plant is Classified:Cotton: 

Example of how a Plant is Classified: Cotton Kingdom Plantae  -- Plants Division Magnoliophyta -- Flowering plants Class Magnolionsida-- Dicotyledons Order Malvales Family  Malvaceae -- Mallow family Genus Gossypium Species hirsutum Upland cotton  Variety: Delta Pine 555 BG/RR

Corn: 

Corn Plantae Spermatophyta       Magnoliophyta Liliopsida Cyperales Poaceae Zea mays Pioneer 32 D 99

Slide8: 

For the purpose of crop production, this lecture deals strictly with vascular plants.

Vascular Plants include Seedless and Seed Plants: 

Vascular Plants include Seedless and Seed Plants Ferns and fern allies are seedless plants Reproduction occurs by spores. Includes whisk ferns, club mosses, horsetails, and ferns.

Angiosperms v/s Gymnosperms: 

Angiosperms v/s Gymnosperms Angiosperms- FLOWERING PLANTS--vascular plants that produce seeds that are enclosed inside a fruit. Gymnosperms- NAKED SEED– vascular plants that produce seeds on cones

Slide11: 

Dicot versus Monocot

Dicot or Monocot?: 

Dicot or Monocot? C D E F A B

Is this plant herbaceous or woody?: 

Is this plant herbaceous or woody? Herbaceous- Herbaceous plants are plants with non-woody stems whose above-ground growth dies back in winter in the temperate zone. Woody- plant that contains wood. A C B

What is an annual? : 

What is an annual? Annual: A plant that germinates, grows, flowers, produces seed and dies in the course of a single growing season.

What is a Perennial?: 

What is a Perennial? A plant that lives more than two years or three seasons and normally flowers annually. Many die down during the winter but the roots are unaffected by frost and new growth appears as the weather improves and the temperature rises.

What is a biennial?: 

What is a biennial? A plant sown one year to flower or fruit the next, then dying or being discarded. Many vegetables are biennial, but are treated as annuals and harvested in their first year before they have flowered.

Parts of a Plant : 

Parts of a Plant

The Leaf: 

The Leaf

Functions of a Leaf: 

Functions of a Leaf Leaves Photosynthesize Process that requires water, carbon dioxide, and sunlight to enable plant to produce food. Protect buds Attach to objects (tendrils) Store food (bulbs) Capture insects

Parts of a Leaf: 

Parts of a Leaf

Leaf Venation: 

Leaf Venation

Leaf Types: 

Leaf Types simple compound needle

Leaf Arrangement of Simple Leaves: 

Leaf Arrangement of Simple Leaves

Leaf Arrangement of Simple Leaves: 

Leaf Arrangement of Simple Leaves

The Root: 

The Root

Functions of a Root System: 

Functions of a Root System Anchor the plant Absorb water and minerals for the plants use. Root hairs are important for their absorptive capacity. Produce hormones that stimulate growht Store products of photosynthesis

Types of Roots: 

Types of Roots Taproot Fibrous Fleshy

Root Parts: 

Root Parts Root hairs Root cap Meristem

Slide30: 

The Stem

Functions of the Stem: 

Functions of the Stem Is the main axis of the plant along with its lateral branches Provide support Has vascular tissue to transport water, minerals, and products of photosynthesis Specialized stems serves as storage

Stems as Food Reservoirs: 

Stems as Food Reservoirs Stem Tubers usually grow underground but have buds or "eyes" from which spring new stems. • Corms are solid masses of stem tissue. They are actually a condensed stem with a bud on top from which the new stem grows. Bulbs are compressed stems containing a growing point (bud) or flower bud enclosed by thick, fleshy scale leaves.

Stems as Food Reservoirs: 

Stems as Food Reservoirs Rhizomes are horizontal, elongate and underground, often thick and fleshy (A) Stolons are horizontal, above-ground, often rooting at the nodes (B) A B

The Flower: 

The Flower

Flower Function: 

Flower Function Flowers consist of several kinds of highly modified leaves. Flowers serve to house the reproductive organs of the plant.

Reproductive floral organs: female: 

Reproductive floral organs: female Carpel or pistil – female reproductive organs; contains: Stigma – is where pollen sticks to Style – is the long tube that connects stigma to ovary Ovary – enlarged structure at the base of carpel/pistil where the ovules are located; it will become the fruit. Ovules – contains female gametophyte, becomes the seed.

Reproductive floral organs: male: 

Reproductive floral organs: male Stamen – male floral organ, consists of: Anther – part of the stamen that produces pollen Filament – stalk-like structure that holds anther Pollen – immature male gametophyte

What is pollination?: 

Pollination: The transfer of pollen from the male anther to the female stigma What is pollination?

Why is pollination important?: 

Why is pollination important? Sexual reproduction produces variable offspring, creating diversity and variation among populations (shuffling of genes). Sexual reproduction is advantageous to an organism only if it happens with someone other than itself!

How do plants get pollen from one plant to another?: 

How do plants get pollen from one plant to another? Because plants are rooted in the ground, they must use different strategies: WIND POLLINATION: Gymnosperms and some flowering plants (grasses, trees) use wind pollination. Flowers are small, grouped together Not a very efficient method (too chancy and wasteful)

Pollen Dispersal by animals : 

Insects (bees, wasps, flies, butterflies, moths) Birds – hummingbirds, honey creepers Mammals – bats, mice, monkeys Reptiles and amphibians Pollen Dispersal by animals

What is fertilization?: 

What is fertilization? Fertilization: The joining of sperm and egg in an ovule within the ovary.

Describing flowers: 

Describing flowers Perfect flower- has stamens and pistils Imperfect flower Stamenate flower- has no pistil Pistillate flower- has no stamen

Acer rubrum (Red maple): 

Acer rubrum (Red maple) Staminate flower Pistillate flower

Describing flowers: 

Describing flowers A complete flower has all of the following parts: sepals, petals, pistils, and stamens. Incomplete flower is missing one or more of the parts needed to make it complete

Monoecious or Dioecious?: 

Monoecious or Dioecious? If ONE plant has both staminate and pistillate flowers on it, it is said to be MONOECIOUS. If ONE plant has only staminate or only pistillate flowers on it, it is labeled DIOECIOUS.

Slide50: 

Monoecious Dioecious Stamen Pistil

Fruits and Seeds: 

Fruits and Seeds A fruit is the mature ovary of the flower that usually contains seeds. Pericarp

Slide52: 

Flower and Fruit Relation

Categorizing Types of Fruit: 

Categorizing Types of Fruit Fruits at maturity can be divided into 3 categories: Dry indehiscent Dry dehiscent Fleshy (not dry at maturity) indehiscent

Slide54: 

Dry indehiscent achene - seed not adnate to the pericarp samara - a winged achene caryopsis - seed adnate to the pericarp nut - pericarp lignified

Slide55: 

Dry dehiscent follicle - dehiscent via only a single suture legume - dehiscent along two sutures

Slide56: 

Fleshy berry -  multiseeded and derived from a compound pistil - a fleshy capsule drupe - single seed (usually) with pericarp differentiated into 3 layers

Fleshy Fruit: 

Fleshy Fruit

Slide58: 

Plant Science is a very complicated topic, but with this module we hope that you have gained a general understanding of plants. For more information, contact your local County Extension Office. Questions or comments?