Transcript Seedless Plants April 2012

Kingdom Plantae
What do we know about plants
 This may seem like a basic question, but what do you
really know about plants?
 How many species can you name?
 How many of you have actually planted something
before?
 What environments do plants need to grow?
Kindom Plantea’s Diversity
Plants include everything from pond scum to the giant California
Redwoods, grasses to Venus fly traps. There’s a lot in this kingdom.
Common Characteristics to all…
 So what makes a plant a plant? What are the
characteristics that are common to all organisms in this
kingdom?
 They all need…
 Need water
 Carbon dioxide
 Sunlight
 These are necessary for the process of photosynthesis.
 Other than this the sky’s the limit!
Algae, horse tails, moss and ferns
 These plants can be separated from the rest based on
one criteria. They don’t actually produce seeds.
 We will examine each one individually, but lets start with
Algae.
 Generally multicellular and aquatic
 Lack VASCULAR TISSUE, leaves, stems and roots.
 So you might ask yourself…what do they have then?
 Vascular tissue refers tube like cells that transport water
and other substances internally.
Horse tails and Moss
Worst weed to pull….ever…
Ferns
Just an all around nice plant to look at.
Algae
Forests of the sea and the first on our list…
 Think about the last time you were on the beach, what
kind of marine plants washed ashore? What unique
features and characteristics did they have?
 Most plants cannot live in saltwater, since the water
drowns their roots and the salt poisons their systems.
Seaweed, however, is not a true plant and does not use
systems that can be waterlogged. It has thick, rubbery
stems that protect it from the corrosive ocean water, and
uses simplified versions of roots and leaves to hold it in
place and absorb sunlight. More complicated types of
seaweed even have specialized bladders that allow it to
float.
Seaweed.
Quiz:
 What does analogous structure mean?
 Name the equivalent of Roots, leaves and stems in algae
 Name two characteristics of seaweed that help is survive
 Why do we see plants as green?
 What makes Clammy Danny so independent?
Algae’s Analogous structures:
 So although they lack true stems,
leaves and roots, they have
analogous structures (similar but
from different origin)
 To put it another way, they are
similar functions but structures.
Simplified Structures
 The Algal structures are generally a
simplified version of a vascularized plants
structures.
 Instead of roots they have HOLDFASTS
 Instead of stems they have STIPES
 Instead of leaves they have BLADES
 It actually sounds way cooler to me.
 They also have floats as well.
How do their structures help?
 How do the algae’s
unique structures
help them in their
environment.
 What happens to
them in a terrestrial
environment?
Not all Algae look the same.
 Remember way back in science class (when it was still
called science!) and you looked at rainbows and the
colour spectrum? I didn’t think so….
 We’ll if you remember correctly the reason we see
certain colours is because they are reflected back at us,
while absorbing the rest. Pretty awesome actually.
 White reflects everything and black actually absorbs
everything….
Photosynthesis
 Well photosynthesis relies on ‘colour’ or lights energy
which is seen in the different wave lengths.
 CHLOROPHYLL reflects green light black, absorbing red
and blue. It is the essential pigment molecule for making
GLUCOSE.
Pigments Photosynthesis and Depth
 Classification of Algae is based on the type of
Chlorophyll they possess.
 Depending on the depth of the ocean the algae inhabit,
different wave lengths will be present. The deeper you go
the more blue light that will reach it. Therefore that is the
colour (wave length) that will be absorbed
 At the deepest depths Red Algae (phylum Rhodophyta)
will be found. Mostly found in marine environments
Brown and Green Algae
 Phylum Phaeophyta: Brown Algae,
 store their food as starches and oils.
 Usually yellowy brown in colour
 Mostly marine
 Phylum Chlorophyta: Green Algae,
 Store their food as starch which is a carbohydrate
 Have cell walls of cellulose*
 Found in fresh water and marine (salt water)
environments.
 *much like terrestrial plants
Quick Review
 Seaweed comes in three different varieties: green, red and brown
(although blue-green algae is sometimes considered a type of
seaweed as well). Green algae grows only three feet long at the
most, and is most useful for sea creatures, who eat and hide in it.
Red algae has the most applications to human industry, but brown
algae includes the kelp family and grows by far the largest out of
the three varieties. The forests that brown algae create are home
to unique environments of marine life that can survive nowhere
else.
 Certain kelps are edible and used in different dishes, but red algae
is harvested in large quantities to produce a vegetable gelatin
used in a large number of foods and cosmetic products. Some of
the larger kelps are also used to create fertilizers, medicines and
dietary chemicals.
A close look at Green Algae
 We will examine four types of green algae based on their
structure from basic to complex. We move from a basic
single cell living organism which resembles prokaryotes to
more complex common plant structures.
 Unicellular Chlamydomonas
 Colonial Volvox
 Filamentous Spirogyra
 Leaf like Ulva
Chlamydomonas
 Chlamydomonas:
 Unicellular:
 Egg shaped
 Two flagella
 Found in damp soil and ponds
 Possess eye spot
 Pyrenoid body
 Starch production
 Contractile vacuoles
 Water balance
Close Up View
Break Time!

http://www.dailymotion.com/video/x92drm_seaweed-secrets-prince-edwardislan_travel

http://www.france24.com/en/20090815-environment-sea-invaders-algae-jellfishcarp-France-beach

Review: Analogous structures….and examples GO

Three types of seedless plants

Three Phylum of Algae…



Rhodophyta, Red Algae
Phaeophyta: Brown Algae
Chlorophyta Green Algae

What is our Perception of seaweed? How do you think other cultures view it? What
role do you think it may play in the future of aqua agriculture.

http://news.nationalgeographic.com/news/2010/07/photogalleries/100730environment-china-green-algae-pollution-pictures/
Volvox: Colonial Bacteria
 The next step in complexity is moving from single cell to a
colony or group of cells living together.
 Volvox is part of a Colonial living arrangements is an
important step in understanding the complex transition
between single cell to multicellular organism.
 1. Potential for repair and regeneration
 2. exchange of cytoplasm and chemicals communication
 3. a few specialized cells. (Sexual reproduction)
 Primitive organ characteristics.
 Volvox is also Mobile: It can move about.
Spirogyra: filamentous plants
 What exactly is filamentous mean again?
 When algae begin to form long chains this is referred to as
filamentous. A number of colonies begin to clump
together end to end.
 Spirogyra: you may recognize this algae as the pond
scum and slime you find near most slow moving water.
 Reproduction: Fragmentation: organism which can
continue to grow when its filamentous chain breaks.
Holdfast:
 Spirogyra also are the only one
of the three phylum of Green
Algae we have discussed which
posses a Holdfast
 If you remember, a holdfast is
equivalent to a root system
which allows the filamentous
chains to become anchored to
one area making them sessile.
 Sessile: fixed in one place.
S
Ulva: Lettuce of the Sea
 Basic characterisitcs
 Leaf-like Blades
 Different body plan from previous 3 green algae
 More complex life cycle than previous
 Sexual and asexual phases of their life cycle
Sexual and asexual reproduction
 Okay this might be a little confusing.
 Zygote: represents a complete set of DNA and paired
chromosomes through fertilization, this is represented by the symbol
2N.
 These zygotes begin to grow producing Sporophytes (which are
spore producing plants) and are DIPLOID meaning they contain
pairs of chromosomes 2N.
 Spores are different than seeds because:
 They are not the result of fertilization involving male and female
 Lack stored food for germination
 And will germinate (begin growing) if they land in a suitable environment
Sporophyte life cycle
 However a sporophyte produces HAPLOID flagellated
spores through meiosis.
 Haploid means does not contain pairs of chromosomes
(N).
 Meiosis: cell division where cells end up with ½ set of
chromosomes. Necessary for sexual reproduction and
leads to genetic variability.
 Indicated by + and – symbol to represent different
genetics, not male and female.
Gametophyte life cycle
 The plants that are produce from these HAPLOID spores
are called GAMETOPHYTES (N) and will give rise to
gametes.
 The key difference during this phase of the life cycle is
that the gametes (+, -) must pair up and fuse together to
form a zygote (Complete set of DNA 2N)
 The Gametophyte plant is structurally similar to
Sporophyte plant.
Chromosomes
 In humans we
have 23 pairs.
You receive
one set from
you mother
and one from
your father.
Big Question: Write ‘em down!
 Okay lets not get greedy here, why do some plants
require both asexual and sexual reproduction. Why don’t
animals have this option?
 Do you think the divisions that scientists have created for
organizing life work?
 IE moving from relatively simple to more complex life cycles.
 Is life really represented by a spectrum or is it an evolutionary
continuum?
 What role do you think these simplified organisms may
play in the future of science?
Alternation of Generation
 This alternation of generation is highly significant in plants, as
it increases the chances of the plant's survival in the long
run. The next generation becomes even more adapted to
the environment. The formation of spores from parent cells,
cause shuffling of genes, conducing to new, different and
stronger genetic make ups. It also allows for easy and rapid
reproduction of the species.
 Then in the gametophyte stage, when gametes are formed
the with new variations of complete genetic information,
the zygote formed is better adapted to the environment.
Thus, the gametophyte and sporophyte generations are
truly significant phases in the life cycle of a plant.
 This concept will be key as we begin to study Land plants.
Algae is all around us!!!!!
 Algae are a rich source of carbohydrates, protein, enzymes and fiber.
Besides, many vitamins and minerals like vitamin A, C, B1, B2, B6, niacin,
iodine, potassium, iron, magnesium and calcium are abundantly found
in algae. Being such a rich source of essential nutrients, they are a major
source of food, especially in Asian countries like China, Japan and
Korea. Algae are also used in producing nutritional supplements.
Seaweeds are an important food supplement for animals and can also
be used as fertilizers. Algae also have the potential of producing
vegetable oil.
 Algae extracts are used in food, cosmetics and pharmaceutical
industries. Agar is mainly used as a preservative in canned meat and
fish and as a gelling agent in food. Carrageenans are used in
toothpastes, ice-creams, pet foods, lotions and as a stabilizing agent in
dairy products.
Facts continued
 Controlling pollution. They act as biofilters, and so are being used in the
treatment of waste water to make make it suitable for human use. Even
some power plants also use algae to reduce the carbon dioxide emissions,
where carbon dioxide is poured into some tanks or ponds in which algae are
fed. In farmlands, they are used for capturing the run-off fertilizers that can
pollute the water bodies.
 Algae can be used is to produce biodiesel, which has a bright possibility to
become an efficient alternative source of fuel, it is environmental friendly
and can prove to be effective in regulating global warming and climate
change by controlling the level of pollution.
 In addition to all these uses, algae have been a part of traditional medicine
in treating a number of ailments since ancient times, especially in Asian
countries. Such diseases include cough, hypertension, diarrhea, gout, etc. As
they have a high content of iodine, their consumption can lower the risk of
goiter. Now, algae are being studied to find out if they could be used in the
treatment of cancer.
Just a simple tail?
 Flagellum:
http://www.youtube.com/watch?v=0N09BIEzDlI&feature
=related
 Flagellum Nano technology:
http://www.youtube.com/watch?v=7NFgjiumiAw&featur
e=related