Naturalists at Large: Plant kingdom

THE PLANT KINGDOM

7 Basic needs of plants:

*temperature

*light

*water

*air

*nutrients

*time

*room to grow

All plants:

*eukaryotes and autotrophic.

*Most live on land and have a way to obtain water.

* Many have a waterproof layer covering their leaves called the cuticle - prevents water loss.

Life Cycle of Plants

Two stages:

Sporophyte - the plant produces spores

Gametophyte - the plant produces 2 kinds of sex cells (gametes) sperm

cells and egg cells

Two major divisions of plants

Vascular Plants - those that have vascular tissues (tubes that transport water throughout the cell

Nonvascular Plants - those that have no vascular tissues and must be completely connected to the ground

The three kinds of nonvascular plants are mosses, liverworts and hornworts.

MOSS

Mosses: green fuzzy part you see is the gametophyte Root-like structures called rhizoids anchor the moss & absorb water and nutrients from the soil. Has a long thin stalk with a capsule on the end that contains spores. They live on tree trunks and rocks.

LIVERWORTS

LiverwortsLiverworts grow flat along the ground on moist rocks and soil along streams. They look like a human liver.

HORNWORTS

Hornworts look like liverworts except that they have curved structures growing out of them. They live in moist soil mixed in grasses.

Two main divisions of vascular plants:

1. SPORE PRODUCERS (ferns, club mosses and horsetails)2. SEED PRODUCERS

VASCULAR PLANTS

Ferns, club mosses and horsetails need moist surroundings so spores will survive and grow into gametophytes. When the gametophytes produce egg and sperm cells, there must be enough water nearby for fertilization to occur.Most club mosses and horsetails have become extinct …

All other plants are seed plants. They have two types of vascular tissue (xylem and phloem) and use seeds to reproduce.

Cells of stems are xylem, or phloem - located in long strands called vascular bundles.

xylem xylem cells:cells:

move water in plants.

phloem phloem cells:cells:

move food down the stem to other parts of the plant.

TWO TYPES OF STEMS:

woodywoodyStems that are hard and stiff. These stems usually don't die back to the ground during the winter. These are stems we use to make furniture and houses.

herbaceousherbaceousPlants with stems that are usually soft. These stems die back to the ground every year.

Two types of seed plants:

GYMNOSPERMS:•Woody stems(conifers)• Produce naked •seeds not enclosed in an ovary•Needle like leaves

REPRODUCTION IN GYMNOSPERMS

Conifers produce male and female cones - sometimes cones are produced on separate trees

Male cones produce pollen

Females produce one ovule at base of cone

Pollen falls from male on to female.

In time sperm and egg cell join in ovule.

Zygote develops into embryo.

POLLINATION: Transfer of male reproductive structure

to female reproductive

structure

Seed develops & cone size increases.

Cones with immature seeds point up & cones with mature seeds point down.

ANGIOSPERMS:2nd type of seed plant •Herbaceous stems

•Produce stems in enclosed fruit

•two characteristics - produce flowers and fruit

PARTS OF THE FLOWER:

The stigma is the sticky surface at the top of the pistil; it traps and holds the pollen. The style is the tube-like structure that holds up the stigma. The style leads down to the ovary that contains the ovules.

The stamen has two parts: anthers and filaments. The anthers carry the pollen. These are generally yellow in color. Anthers are held up by a thread-like part called a filament.

Petals attract pollinators.

The sepals are the green petal-like parts at the base of the flower. Sepals help protect the developing bud.

Seeds develop once the sperm cells fertilize the egg cells. The seed provides a covering to keep the young plant from drying out. All seeds have an embryo, stored food and a seed coat.

•The young plant that develops from the fertilized egg is called the embryo. •The embryo has the beginnings of the roots, stems and leaves. •The embryo uses the stored food inside the seed to grow. •The stored food is in cotyledons. The outer part is called the seed coat.

TWO TYPES OF ANGIOSPERMS

DICOT: examples are roses, violets and dandelions, oak, maple, vanilla bean and apple

•Flowers have 4 or 5 petals or multiples of that number

•Leaves are wide with veins that branch off each other

•Stems have bundles of vascular tissue arranged in a circle.

MONOCOT:

Examples are grasses, corn, wheat, rice, lilies, tulips

•Slender leaves with veins that run parallel like train tracks

•Vascular tissue is scattered randomly through stem

Life CycleLife Cycle

A plant's life cycle describes how long a plant lives or how long it takes to grow, flower, and set seed. Plants can be either an annual, perennial, or biennial.

AnnuaAnnuall A plant that completes its life cycle in one growing season. It will grow, flower, set seed, and die

Examples: marigolds, tomatoes, and petunias.

Perennial Perennial

A plant that lives for 3 or more years. It can grow, flower, and set seed for many years.Examples: daisies,

chrysanthemums, and roses.

(think bushes!)

Biennial Biennial A plant that needs two growing seasons to complete its life cycle. Produces leaves one season, rests in winter and grows flowers & seeds the next season.

Examples: parsley, carrots, & foxglove.

Plant Parts - Roots

The roots provide support - anchor the plant & absorb water and nutrients needed for growth.

I’M A

ROOT!

ROOT SYSTEMSROOT SYSTEMS

Taproot systemA root with a few branches that is very thick and swollen. Carrots & potatoes are example.

fibrous root systemfibrous root systemSome plants have a root system like this. It is a bunch of very fine roots all together. Grass plants have fibrous roots.

Plant Parts - StemsPlant Parts - Stems

Stems carry water and nutrients taken up by the roots to the leaves. They also provide support. Without stem, there would be nothing to hold up leaves or flowers!

Plant Parts - LeavesPlant Parts - LeavesLeaves are the food making factories of green plants.Leaves can be simple, made of a single leaf blade OR...

compound in which the leaf blade is divided into separate leaflets

Joins leaf to main stem

Joins leaf to main stemJoins leaf to main stem

LEAF CELLSLEAF CELLS

Leaf Functions:Leaf cellLeaf Functions:Leaf cell