What next?

• Now we have a basic understanding of the basic plant parts, now it is time to learn in more details the structure and composition of those parts.

• There are several major characteristics that are used to classify plants into their different phyla

How plants are classified

• Non-vascular plants (no seeds)

• Vascular plants without seeds

• Vascular plants with seeds– Non-flowering – Flowering

• Monocotyledon (monocot)• Dicotyledon (dicot)

The 4 Plant Kingdom Phylums

Plant Phyla Examples Classification Characteristics

Bryophyta Mosses Non-vascular

Pteridophyta Ferns Vascular without seeds

Coniferophyta Cedars, junipers, pines, redwoods, yews

Vascular, with seeds, non flowering

Anthophyta Flowering plants Vascular with seeds flowering

Vascular vs. Non-vascular

• Vascular plants are those that have vascular tissue those that do not have vascular tissue are non-vascular.

• So what is vascular tissue?– Vascular tissues are xylem and phloem which

carry water and minerals to the plant.

Vascular Tissue

Responsible for transporting food, water and other substances around the plant.

There are three main types of Vascular Tissue:

Phloem (this one gets the food)

Cambium (this one is between the other two)

Xylem ( this one gets the water)

Non Vascular Plants• Kingdom Plantae• Division Bryophyta

– Examples – Mosses

• Characteristics– Small no more than an inch or so.

– No vascular tissue – no true roots, stems or leaves.

– Transport water into the leaves by diffusion• Leaves are often single layers of cells so that diffusion can easily be

accomplished.• Usually have to live near water in shady places

– Mosses are made of 2 parts • a lower leafy part attached to rhizoids.

– Anchors the plant and absorbs water and minerals

• The upper part consists of stalks.

– Reproduction– The gametes (eggs and sperm) are produced in the stalks.

– Eggs are non-motile the sperms are motile. Water is necessary for reproduction so that the sperm can swim to the non-motile egg.

Non-vascular PlantReproduction

• In mosses the eggs and sperm needed for sexual reproduction are produced in the top of the green leafy part of the plant. Water is necessary for fertilization because the sperm must swim to the unmoving egg. After fertilization the zygote remains attached to the green leafy part and grows into the stalk and capsule. Thousands of spores are produced in the capsule. When conditions are right, the capsule bursts open and the spores are released.

Non-vascular PlantReproduction

Seedless Vascular Plants

• Kingdom Plantae• Division Pteridophyta

– Examples – Ferns

• Characteristics– Contain xylem and phloem so can grow taller and live in drier areas.

• Still rely on water for the transport of gametes for sexual reproduction

– Fern have 3 parts• Fronds – the leaves

• Rhizome – and underground stem

• Roots – anchor the plant and transport water and minerals to the plant

– Reproduction• On the lower surface of the fern fronds are specialized structures that produce spores.

• The spores are scattered by the wind.

• The spores grow into a small heart shaped type of fern plant.

• This small plant produces the eggs and sperm

• Water is required to allow the sperm to swim and fertilize the egg.

• After fertilization the small plant remains attached to the small plant and will then grow into the fern that

Seedless Vascular PlantReproduction

• On the lower surface of many fronds are specialized structures that produce spores (which are haploid). Tiny fern spores are scattered by wind and may eventually fall on a surface and begin growing. The spores grow into small hook-shaped plants that are often easily overlooked. It usually grows no larger than a fingernail. The small plant produces eggs and sperm and requires water for the sperm to swim to the eggs. After fertilization, the zygote which remains attached to the small plant will grow into the type of fern that most people recognize.

Seedless Vascular PlantReproduction

Seed-bearing Vascular Plantsnon-flowering

• Kingdom Plantae• Division Spermothphyta• Sub-Division Gymnosperm• Characteristics

– Contain xylem and phloem

– Seeds are usually contained in cones• Gymnosperm means “naked seed”

• Seeds are not completely covered

– Do not produce true flowers

– Woody plants – only some produce annual rings

– Many have needle like leaves

– Usually evergreen (stay green all year long)

– Have many commercial uses: Paper, housing, flooring, furniture etc.

– Reproduction• Detailed on next slides

Seed-bearing Vascular Plantsnon-flowering

Seed-bearing Vascular Plants non-flowering Reproduction

First the pine tree must produce two different kinds of cones. The seed cone and the pollen cone. The seed cone containing the egg and the pollen cone containing the pollen grains.

The spores in the gymnosperm's seed cone become the female gametophyte and produce the eggs that are fertilized by large amounts of blown (by the wind) pollen grains. Which is the spores in the pollen cone known as the male gametophytes.

Seed-bearing Vascular Plants non-flowering Reproduction

When the pollen (sperm) and ovule (egg) join, a diploid zygote is formed.

Then the fertilized egg divides through mitosis and grows into and embryo inside a seed in the seed cone. The embryo being a young sporophtye.

Finally the seed will be shed and will soon reach a suitable environment for it to grow into a new gymnosperm. To make it possible to grow it uses the stored food inside of the seed.

The cycle reoccurs when the cones are ready.

Seed-bearing Vascular PlantsFlowering

• Kingdom Plantae• Division Spermatophyta• Sub Division Anthophyta (angiosperm)• Class

– Class Monocotyledon– Class Dicotyledon

• Characteristics– Contain xylem and phloem.

– Seeds are covered by a protective covering called a fruit• Angiosperm means “covered seed”

– All produce flowers

– Usually deciduous (loose leaves in winter)

– Have many commercial uses: All Fruits and vegetables, honey, baskets, etc.

– Reproduction• Will cover this next week

Seed-bearing Vascular PlantsFlowering

• Anthophyta (angiosperms) are divided into 2 classes– Monocotyledons– Dicotyledons

• So what are they?– First we need to know what a cotyledon is.

What is a Cotyledon?

This is the first type of leaf to grow on a plant.

After the first true leaves have formed, the cotyledon leaf withers and falls off.

Anthophyta (flowering plants): Monocotyledon

Monocotyledon plantsMono means one. Has only 1 cotyledon

(Monocot for short)Starts growing with one leaf.Flower parts in multiples of 3Major leaf veins parallel Stem vasular bundles scatteredRoots are adventitousSecondary growth absentExamples: grasses, orchids, lillies,

tulilps, corn, bamboo, and daffodils

Anthophyta (flowering plants): Dicotyledon

Dicotyledon plantsDi means two. Has 2 cotyledon’s

(Dicot for short)Starts growing with two leaves.Flower parts in multiples of 4 or 5Major leaf veins reticulated (palmate, pinnate, etc.)

Stem vascular bundles in a ringRoots develop from radicle. Can be any type.Secondary growth often presentExamples: peaches, pears, carrots, squash etc.

Which is the monocotyledon?Which is the dicotyledon?

• Monocotyledon

• Dicotyledon

As you will recall one of the major characteristics that separate plants is the

formation of tissues

Plants have 3 Types of Tissue Dermal TissueGround TissueVascular Tissue

Plant TissueWhat is tissue?

Cell of the same kind joined together.Most Plants are Made of 3 Types

of Tissue

Dermal Tissue

Ground Tissue

Vascular Tissue

Dermal Tissue

• This type of tissues is on the surface of most plants.

• Its purpose is for:– protection and the – prevention of water loss.

Ground Tissue Forms the bulk of the plant’s insidesPhotosynthesisFood storageSupport and Protection

Vascular Tissue

Responsible for moving food, water and minerals around the plants. Xylem and Phloem

Vascular Tissue is Made of:

• Phloem • Xylem

This carries the food made in the leaves to other parts of the plant.

This carries water up from the root.

• Cambium These cells are able to divide

to make more phloem and xylem tissue. (Dicots only)

Cross section of a monocot stem

1. A large number of vascular bundles.

2. The vascular bundles are scattered in the ground tissue.

3. No cambium occurs between the xylem and phloem.

4. There is no distinction between the cortex and pith.

5. No Secondary thickening.

6. No annual rings are formed.

Cross section of a dicot stem

1. A limited number of vascular bundles.

2. The vascular bundles are arranged in a ring.

3. Cambium occurs between the xylem and phloem.

4. The cortex and pith can be clearly distinguish.

5. Secondary thickening can occur.

6. Annual rings are formed due to secondary thickening.

Monocot vs. Dicot stem

Cross section of a young dicotyledon stem

• Phloem• Cambium

• Xylem

• Vascular Bundle

• In young dicotyledon stems, vascular tissue is

usually arranged in groups called Vascular Bundles. In dicotyledon stems these bundles are arranged in a regular pattern as shown above.

• Young Dicotyledon• Vascular Bundles

• Older Dicotyledon

• Vascular Cylinder

• So…As the young dicotyledon grows older, the vascular bundles join forming a continuous circular shape called Vascular Cylinder.

• Each year a new layer of phloem and xylem are produced.

• Young dicotyledon stem• Slightly older

• Older still

• After another year– Now an older dicotyledon

• After a number of years

After a number of

year..

In the older stems the epidermis is replaced by bark.

Over time, the stem and roots thicken and the plant becomes known as a Woody plant (a tree).

Many years of xylem

Many years of phloem

• This is a cross section of a tree.• It is about 30 year old.  • Wood that grows in the spring makes a light-colored ring and is

called spring wood (green dot).• In the summer trees don't grow as much. Wood that grows in the

summer makes a dark-colored ring. It is called summer wood (white dot).

• Summer wood and spring wood have different thickness' depending upon weather conditions that year.

• 1 light-colored ring + 1 dark-colored ring = 1 year.This is called a annual ring.

Heartwood and Sapwood• Annual rings can tell the

story of the tree. It can also tell you how old a tree is

• The older darker colored wood, no longer has xylem carrying water in it. It is called the heartwood. Heartwood contains tannins, resins, and gums which make it very hard and resistant to insects and fungi.

• The lighter colored wood still has functioning xylem in it. It is called sapwood.

Movement of Fluids What type of tissue moves water and food to all parts of a plant? Vascular Tissue

What type of tissue carries the water from the root to the leaves?Xylem

What type of tissue carries food (which is dissolved in water) from the leaves to all other areas ?Phloem

TranslocationThis is the movement of fluids inside the plant.

Transpiration • Water is pulled up through the xylem much like a straw.

• Then the water escapes as vapor through tiny holes called stomata.

• Water vapor escaping through a stoma.

• Guard Cells

Overview of water movement• Water enter the plant

through the roots. • The water is translocation

through the plant to the leaves by capillary action.

• The water is used in photosynthesis and converted to oxygen which then escapes through the stomata in the process of transpiration.

Transpiration is a part of the Water Cycle.

The Water Cycle – also know as:

Transport of SugarsPlants create more sugar than they needPhloem moves the sugars to the different parts of the plantExcess sugars are stored as starch.

Some plants convert starch to lipids like peanuts, corn, and olives

Pulling it all togetherNow that you have studied all the parts of the

leaves and all the tissues, study the diagram below and be able to label it