Plants: Grouped by characteristics

Vascular Three main parts: roots, stems and leaves

Roots can be different sizes: Fibrous and tap roots

Storage roots; beets, carrots, sweet potatoes and turnips

Roots have different functions: anchoring the plant, taking in water and minerals, and store food.

Nonvascular Simple; most grow in moist places No vascular tissues.

Vascular Plants: Stems Function of stems

Support, transport of water & food Most stems grow upward Some stems grow sideward

Types of stems Green Woody

Transport of materials Xylem & phloem

Vascular Plants: Leaves Leaves come in variety of shapes and

sizes Leaves are arranged in different ways

Plants are classified by characteristics.

Plants that make seeds Plants that do not make seeds

Flowering Plants

Conifers Ferns Mosses

Plants reproduce differently

Reproduce – it means “to make more of the same kind”

a protective covering that surrounds the seed

anchor the plant in place and absorb water and other minerals from the soil.

carries water and food to the rest of the plant.

makes the plant's food.

makes seeds.

Basic Plant Structure

Some flowering plants are

dicot seed – a seed that has two seed leaves that contain stored food

monocot seed – a seed that has one seed leaf and stored food outside the seed leaf

Parts of a seed

Dicot

Monocot

Seed coat

Epicotyl

Cotyledons

Hypocotyl

Seed coat

Endosperm

Epicotyl

Hypocotyl

RadicleCotyledon

Seed Germination

Monocot Dicot

Hypogeous

Epigeous

Radicle

Leaf Morphology

Leaf Morphology

Structure: Leaf Types

Structure: Leaf Venation

Structure: Leaf Arrangement

Woody Plant Stem

Stern 2006

Woody Stem Structure

What are the critical parts of a tree?

Xylem (earlywood/latewood)

Bark

Cambium/Phloem

Wood Plant Stem

Stern 2006

ANGIOSPERMSThe flowering plants

Spring crocus Crocus vernus

Flower structure Flowers are reproductive structures The have evolved to send and receive

pollen from one flower to another This is process of pollination Flowers are developed from a series of

modified leaves These leaves are arranged in a rings

(whorls)

Flower structure

Dog rose Rosa canina

Structure of flowersFlowers are composed

of four whorls. From the outside in, they are:

• Calyx (sepals)

• Corolla (petals)

• Androecium (stamens)

• Gynoecium (pistils)

Flower Morphology

Flower structureStigma

Style

OvaryPetal

Sepal

Filament

Anther

Calyx (sepals)

Outermost whorl Usually green Protects developing

flower Physically Chemically

Made up of SEPALS Sepals free or not Calyx radially or

bilaterally symmetric

Corolla (petals)

Is usually colorful and showy;

Attracts pollinators Guides pollinators; Is composed of petals Petals may be united

or separate; Corolla may be

radially or bilaterally symmetric.

Androecium (stamens)

Is composed of stamens

Stamens have filaments and anthers

Pollen is produced in anthers

Stamens can be free or united

Gynoecium (pistils) Is composed of

pistils A pistil is composed

of an ovary, style, and stigma.

Styles may be separate, branched, or united

Pistils have a slide of their own – just wait

Structure: Flowers- missing parts Floral Parts Structure

Reproduction Sepals, Petals, Complete

Perfect Stamens, Pistil

Sepals, Stamens, Incomplete PerfectPistil

Sepals, Stamens Incomplete Imperfect

Structure- Compound Flower/ Sunflower

Structure- Flower- Compound Pistil/ Strawberry

Structure: Flower Parts

How Do Flowers Make Seeds and Fruits?

Ovary – the bottom part of the pistil in which seeds form

Ovule - the inner part of an ovary that contains an egg

embryo – tiny part of a seed that can grow into a new plant

How Seeds Form After fertilization the flower dries

up and petals fall off, leaving just the pistil and its ovary.

The top of the pistil falls off and the ovary gets larger as one or more seeds form inside it.

When the seeds are formed, the ovary dries up and the seeds fall out.

Corn, Beans, and Peas are seeds that we eat

How Fertilization Occurs When a pollen grain reaches a pistil, it

grows a thin tube to the ovary. Sperm from the pollen grain combines with an egg, and a seed forms.

Fertilization – the combination of sperm from a pollen grain with an egg to form a seed

How Pollination Occurs

Butterflies may carry pollen from the stamen of one flower to the pistil of the the same flower. Sometimes the butterfly may carry pollen from the stamen of one flower to the pistil of another flower of the same kind.

Pollination- the movement of pollen from a stamen to a pistil

Types of pollination Wind Animal Water

Bumble bee Bombus hortorum on red clover Trifolium pratense

Yorkshire fog grass Holcus lanatus

Animal pollination Usually insects Also other flying

animals e.g. hummingbirds or

fruit bats

Cerambycid beetle pollinating bramble Rubus fruticosus

Pollination Pollen grains contain the

male gametes of the plant They are picked up by a

pollinator and transferred to another flower

Plants tend to specialise in pollinators

This ensures the pollen is delivered to same species of plant

Yellow archangel Lamiastrum galobdolon being pollinated by a bumble bee Bombus hortorum

Pollination

Small skipper Thymelicus flavus on marsh thistle Cirsium palustris

Pollination

The honey bee Apis melifera on marsh thistle Cirsium palustris

Pollination Some flowers are

highly specialised to encourage only one type of insect

Fox glove flowers Digitalis purpurea

Pollination Most species of flowering plants are

hermaphroditic Pollen from a flower could land on the

stigma of the same flower or another flower on the same plant = self pollination

Pollen transferred from the anther on one flower to the stigma of another flower on a different plant = cross pollination

Fertilisation Pollination ≠ Fertilisation The male gamete (the male nucleus) has

to get to the egg cell The egg cell lies in an ovule in an ovary at

the centre of the plant The pollen grain germinates on the stigma It grows a pollen tube down the style It male nuclei travel down the pollen tube

to the ovule

Fertilisation

Style

StigmaPollen grain

Ovule

Embryo sac

Pollen tubeOvary

Fertilisation

Egg cell

Polar nuclei

Embryo sac

Micropyle

Fertilisation

Pollen grains of the daisy Bellis perennis

Fertilisation

Germinating pollen grains of blue bell, Hyacinthoides non-scripta

The double fertilisation

Pollen tube

Pollen tube entering micropyle

Male nucleus + egg cell

= zygote (2n)

Male nucleus + 2 polar nuclei = endosperm nucleus (3n)

OvuleNucellus

From flower to fruit

Marsh marigold Caltha palustris

Fruits and seed dispersalAnimal dispersal Strawberry Fragaria vesca

Wind dispersal Ragwort Senecio

Explosive dispersal Bird’s foot trefoil Lotus corniculatus

Animal dispersalWood avens Geum urbanum