Plants Withou

t Seeds

Life Science

Mr. McKay

Multicellular Algae• Algae- Any Simple

plantlike autotroph that uses sunlight to produce food– Scientists do not agree on

the classification of algae• Some think algae should be

classified as protists• Others think should be with

plants

Multicellular Algae• Algae were the first type of plants on Earth

– Oldest fossils are around 900 million years old

• Algae lack the special tubes that transport water and minerals that land plants have– No true roots, stems, or leaves

• Algae do not have seeds– Must live in or near water

Algae Phyla• Algae are divided

into three different phylum– Brown Algae– Red Algae– Green Algae

• They get their names from the Pigments found within their cells

• Pigments– Green Algae has a noticeable pigment that is

the green chlorophyll• This captures light energy for food making

processes– Energy

– Brown and red algae• They both have chlorophyll but it is masked by

other accessory pigments– These pigments absorb light and transfer it to chlorophyll

» These other pigments include: pink, red, reddish purple, and reddish black

Algae Phyla Continued

Brown Algae• Sargassum

– Found in tropics• Perfect environment is calm winds and gentle

waves• Floats on surface by use of tiny air filed sacs that

act as life preservers• Needs sunlight to produce food

• Sargasso Sea– This is a favorite hot spot for eels

• Snake like fishes• Eels lay eggs in Brown algae

– Travel thousands of miles to do so

• Brown algae has long been used as food for humans– In China, Japan, Canada, Ireland, and New

Zealand• Seaweed

Brown Algae

Red Algae• Like brown algae, red algae

is multicellular and live in the ocean.

• Red algae can grow to be several meters long– Never reach the size of brown

algae though

• Some grow as clumps of delicate, branching red threads

• Others produce hard stiff branches that are rich in calcium carbonate

Red Algae• Red algae usually grow

attached to rocks on the ocean floor– Can grow at depths of

170 meters• Far deeper than any other

algae

• How does red algae make food?– Accessory pigments

• They Absorb little light and convert it to chlorophyll

Red Algae• Uses include

– Food• Ice cream• Dressing• Chocolate milk• Frosting

– Agar• A substance that is jellylike and used in growing

cultures of nutrient bacteria

Green Algae• Green Algae

– Similar to land plants• Life cycles• Pigments• Stored food supplies

• Earliest forms– Unicellular– Then colonies– Finally Multicellular

• Uses– Bio-fuel

Green Algae• Green algae and our environment

• Some May live in unusual places– Symbiotic with fungi and lichens

• Assignment Earth• Green Algae

Green Algae• After 450 Million Years

– Land plants evolved• Mosses and relatives• Ferns and complex plants

Land Plants

• Land plants need to– support the leaves and other parts of the body so they

do not collapse– obtain water and minerals– transport food, water, minerals from one part the

structure to another– prevent excess water loss to the environment– Get sperm cells and egg cells together so that

reproduction can occur

Mosses, Liverworts, & Hornworts• Mosses, liverworts, and

hornworts are tiny plants that live in moist places– Found on

• Wet rocks• Damp tree bark• Muddy banks of ponds and

streams• In some cases they may

cover the ground like fuzzy green carpet

– Mosses, liverworts, and hornworts

Mosses, Liverworts, & Hornworts• Size means:

– No need for special transport system as in other land plants• They simply transport

nutrients from one cell to the next

– No need for stems or other supporting structures

Mosses, Liverworts, & Hornworts• Size means:

–They do not need a special adaption to prevent water loss• Such as a waxy

covering–However the

reproduction cells have a thick water-tight coat

Uses of Mosses• Dried Sphagnum

– Mixed with soil to aide in water retention– Also aides in changing the chemical balance

of the soil to improve plant growth– Prevents certain disease causing bacteria– In past, used to cover wounds to aide in

preventing disease causing bacteria to grow

Uses of Mosses• Sphagnum moss

– Under correct conditions Peat may form• This substance

can allow for decay to be slowed greatly

– Ancient times used it to slow decay of bodies

» Peat Moss Mummies

Vascular Plants• Ferns

– They have vascular tissue• Plants that lack this tissue

are nonvascular– Such as algae

• Unlike other seedless plants they do have special adaptations

– Waxy covering– Roots that enable water

gathering– System of tubes that transport

nutrients» This is what is known as a

vascular system

Vascular Plants• Vascular plants are much

more adapted to the land due to the vascular system– The stem is strengthened

with cells that are extremely thick and strong

– This allows ferns to grow in great size compared to the mosses

• Range in height from a few cm to about a meter

Vascular Plants• Ferns

– Although they are better adapted to the land than nonvascular they still are not fully adapted

• They require standing water in order to reproduce

• The water needs to be in abundance for this to occur

• Tiny pockets in the fern’s leaves provide a home for special blue-green bacteria that produce a natural fertilizer

Vascular Plants• Ferns as food

–In spring fern fiddleheads are sold in specialty food stores• When properly cooked

they are delicious• You should not gather

fiddleheads for food unless you are certain they are edible