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Kingdom: Plantae

Plants …

Plants are multicellular

Eukaryotes that have cell

walls made from cellulose. They

develop from multicellular embryos

and carry out photosynthesis using

the green pigments called

chlorophyll.

Plants …

Are autotrophic

– they photosynthesize.

Are eukaryotic

Have cellulose in their cell walls.

Have an alternation of generations in

their lifecycle.

Lack mobility.

There are MANY different types of

plants. This is how we break down

the types.

PLANT

Aquatic Land

Non-vascular Vascular

Seedless Seed

Angiosperm Gymnosperm

Monocot Dicot

What Plants Need to Survive

Sunlight – energy

Water and Minerals – nutrition

Gas Exchange – require oxygen

Movement of Water and Nutrients –

larger, non-aquatic plants, take in

water through roots and must

transport it to their leaves.

Plants

Plants are Aquatic, Non-vascular or Vascular

Vascular: means to have vessels for transport and support.

The xylem carries water/minerals to the leaves.

The phloem transports food made in the leaves to the rest of the plant.

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Plant Life Cycles

Plants have two alternating phases

A diploid phase (sporophyte)

A haploid phase (gametophyte)

The diploid has two sets of

chromosomes

The haploid has one set of

chromosomes

On page 552, copy the Life Cycle

diagram in the top corner.

Generalized Plant Lifecycle

The gametophyte plant produces haploid

gametes – eggs and sperm. Fertilization

occurs, a zygote is formed. This undergoes

mitosis to produce a diploid sporophyte plant.

Cells of the sporophyte plant undergo meiosis

to produces haploid spores. The spores

germinate to form a gametophyte plant, which

start the process again.

Aquatic Plants

The earliest plants were aquatic. Land

plants had to adapt in order to survive.

-Theses rely on water to disperse their

gametes.

- Roots are below water and may have

floating leaves (water lily)

Bryophytes

Non-vascular land plants

example: Moss

Very small and low to the ground.

Found in moist areas.

Have rhizoids instead of roots and no true leaves.

They rely on water for reproduction. Bryophyte sperm have 2 flagella that help them swim to the egg.

Movement of water, minerals and nutrients is through osmosis and diffusion. (it’s okay, they’re small)

Ferns

Vascular, seedless plants

example: Fiddleheads

Roots, stems and leaves (called fronds).

What we see as a fern is the sporophyte plant.

Stem : called a rhizome, underground and the roots grow downward from it.

The gametophyte plant is the “fiddle head”.

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Vascular Seed Plants

Gymnosperms and Angiosperms

Do not rely on water for the dispersal of gametes.

Wind, animals and insects transfer pollen, which produces sperm to the egg.

A seed (embryo) will form.

Gymnosperms

bear cones.

Angiosperms

are flowering

plants.

Seeds : Three Main Parts

Seed Coat: for protection.

Food source: to feed the developing

embryo.

Embryo: produced from the union of the

sperm and egg; an embryo will

grow and become a new plant.

Gymnosperms: Naked Seeds

example: Conifers (Pine Trees)

YouTube - Gymnosperms

Have “naked seeds” meaning that they have no surrounding fruit.

Conifers have pollen cones (male) and seed cones (female).

Pollen is dispersed; carried by wind.

Pollination occurs when pollen from the male cone comes in contact with the egg in the female cone. A seed is formed.

Female Seed Cone

Male Pollen Cone

Seed

with wing

Angiosperms: Enclosed Seeds

Phylum: Anthophyta

example: Flowering Plants

Flowering plants are the dominant form of plant-life on Earth.

Advantages of being a flowering plant: Flowers attract insects and birds which help to transfer

pollen from one flower to another. Once pollination occurs, seeds are formed.

Seeds are enclosed in an ovary which will become the fruit….

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Classifying Angiosperms

One way of classifying

angiosperms is by

whether they are

monocotyledons or

dicotyledons.

Monocots and Dicots

How many seed leaves?

(and other characteristics…)

Parts of the Flower

All you ever wanted to know

about FLOWERS!

(and probably more …)

Flowers are the reproductive structure of

angiosperms. The ovary is found at the base of

the flower, where it is protected.

The ovary becomes the fruit once pollination

has occurred. It protects the seeds that result

from pollination.

General Structures:

Sepal: green and leaf-like, these are

found at the base of a flower and

enclose and protect the bud.

Petals: colorful structures that attract

birds and insects. The birds and insects

inadvertently act as pollinators.

Male Structures

Stamen: includes the

filament, anther and

pollen.

Filament: thin stalk

which supports the

anther.

Anther: produces

pollen.

Pollen: haploid male

gametophyte;

produces sperm.

Filament

Anther with pollen

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Female Structures

Pistil (or carpel): includes the stigma, the style and the ovary.

Stigma: a sticky patch at the top of the style, where pollen lands.

Style: a long tube through which pollen travels to reach the ovary.

Ovary: contains

ovules (the female

gametophyte);

haploid egg cells will

be produced here.

Ovules have a hole

called a micropyle.

Sperm travel through

this hole to fertilize

the egg which

become seeds.

The remaining

structures become

the fruit.

Stigma

Style

Flowers undergo

Double Fertilization

Within the ovary, an ovule with a megaspore

mother cell produces 8 haploid nuclei.

The nucleus closest to the micropyle

becomes the egg; two nuclei in the center

are called polar nuclei.

Integuments

Pollen grains, from the anther, have

1) a generative cell which produces 2 sperm

nuclei

2) a tube cell nucleus which extends to help the

push the pollen through the style during

fertilization.

The steps:

Pollen touches the stigma.

The tube cell pushes towards the ovary as it moves through the stigma.

As the pollen tube grows, the generative cell produces 2 sperm nuclei.

The pollen tube enters the ovule through the micropyle and the 2 sperm nuclei are released into the ovule.

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Why it’s called double fertilization:

Sperm # 1 + Egg = Zygote (2N)

Sperm # 2 + 2 polar nuclei = Endosperm (3N)

The zygote becomes the embryo as it divides by mitosis.

The endosperm becomes the food supply and is absorbed by the embryo.

The integuments around the ovule harden and become the seed coat.

These three parts make the seeds.

Once the seeds have been made, the flower’s ovary develops into a fruit.