Transcript 5.1 Plants as a bioresource - Blyth-Biology11

PLANT BIOLOGY: INTRO
Unit 5 – Plant Anatomy, Growth & Function
PLANTS IN OUR SOCIETY
• In small groups, brainstorm uses for plants
in OUR society.
USES FOR PLANTS IN OUR SOCIETY
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Fuel (ethanol from corn)
Medicine (aloe vera, med. marijuana)
Tools (wood, toxins in wood to kill fish, weapons)
Food
Construction
Alcohol (potato  vodka; grapes  wine)
To breathe!
Shade
Fragrances
Composting
Narcotics
Clothing (ex. Hemp, cotton)
Dyes, tattoos, henna
Paper
Soaps
Flour, mint, herbs, tea, spices
Make-up, cosmetics, beauty and skin care, jewellery
Important Crops in Canada
(thousands of tonnes)
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Wheat 28, 611
Canola 12, 642
Barley 11, 781
Grain corn 10, 592
Food Security
http://www.youtube.com/watch?v=PiYDG11zIUs
Monoculture
• One type of plant is grown in place of the
natural ecosystem
• What are some pros and cons of this
approach?
Learning Check
• Pg 539, Q 1-6
Medicinal Uses
• 25% of prescription medicines contain plant
extracts
• Rosy periwinkle (vincristine andvinblastine) –
childhood leukemia and Hodgkin’s. Survival
rates have gone from 20% to 90% with these 2
compounds
• Goldenseal – colds and sore gums
• Ginseng – immune system function
Biofuels
• Most biofuels come from corn (ethanol). What are some
pros and cons of this method?
• Research is being done to get fuel from cellulose and oil
from algae
• http://www.youtube.com/watch?v=VI4Qm2AMiEY
• http://www.youtube.com/watch?v=n9_-ZguuhBw
• Read Quirks and Quarks on page 542
Erosion Control
• The paradox of farming: farmers need good soil to farm,
yet farming destroys good soil.
• 2.5 million acres each year are lost to urbanization and soil
erosion.
• About 1/3 of the country's topsoil has been lost due to
urbanization and soil erosion.
Medicinal Plants Assignment
• Pg 573
KINGDOM PLANTAE
• Plants evolved about 500 million years ago from
simple green algae that lived in the ocean.
• All plants are autotrophic and some, like the
famous Venus fly-trap, can also be heterotrophic.
• All plants are eukaryotic and multicellular.
PLANT CELLS
• Like animal cells, plant
cells contain a nucleus
and organelles, but they
have two distinguishing
features:
– Cell wall (made of
cellulose, a complex
carbohydrate, provides
rigid structural support;
difficult to digest)
– Chloroplast (organelle
that conducts
photosynthesis)
Animal cells have lysosomes that release the cellular equivalent of
digestive enzymes. Why don’t plants need these?
PLEASE... CONSIDER THE
FOLLOWING:
• How can plants stand up straight without a
skeleton?
PLANT DIVERSITY
• Currently over 350 000 species of plants,
including:
– Mosses
– Ferns
– Conifers
– Flowering plants
• Most plants live on land and can withstand
a wide variety of climates. Cacti live in arid,
dry areas whereas mosses need to be in
moist environments to survive.
CLASSIFYING PLANTS
• Plants are classified based on the
presence or absence of vascular
tissue
• Vascular tissue can be compared
to arteries and veins: a network of
specialized cells that allows plants
to transport water, minerals and
sugar throughout the plant
• What would you expect a nonvascular plant, without vessels to
transport nutrients and water, to
look like?
Plants
Cannot
transport foot
or water
between plant
parts
Non-vascular
(ex. moss)
Vascular
(ex. tree,
sunflower)
Transport of
fluid is
through
simple
absorption or
osmosis
Contain a
vascular
system
allowing for
transportation
of nutrients /
water
throughout
the plant
Must live in
moist
environments;
need water
for
reproduction
WHAT MIGHT VASCULAR
PLANTS LOOK LIKE?
FUNCTION
OF
STEMS
1.Support system for plant body
2.Transport system carries water & nutrients
(through vascular tissue!)
3.Holds leaves & branches upright
Looking at the
picture below:
What years had
the most rain?
What years
experienced the
worst drought?
FUNCTION OF LEAVES
1. Main photosynthetic organ
2. Broad, flat surface increases surface
area for light absorption
3. Have systems to prevent water loss
• Stomata open in day but close at
night or when hot to conserve
water
• Waxy cuticle on surface
4. System of gas exchange
• Allow CO2 in and O2 out of leaf
Elephant Ear Plant
Leaf Cross-Section
LEAF
STRUCTURES
waxy layer;
2. Veins: transports water,
nutrients and food
– Made of xylem and
phloem vascular
tissue
3. Mesophyll: contains
cells that perform
photosynthesis
b/c they contain
chloroplasts.
Mesophyll
1. Cuticle:
covers upper surface
– Protects leaf against
water loss
Cuticle
Veins
Stoma
(Opening)
2 Guard
Cells
Surround
each
Stoma
LEAF STRUCTURES
4. Guard cells:
• Cells that open and close the stoma
• Conserve water by preventing excess water
transpiration
5. Stomata: openings in leaf’s surface; when open:
• GAS EXCHANGE: Allows CO2 in & O2 out of leaf
• TRANSPIRATION: Allows excess H2O out of leaf
Guard Cells
Stoma
1.
2.
3.
FUNCTION
OF
Anchor
& support plant
in the ground
Absorb water &
minerals
Hold soil in place
Root Hairs
ROOTS
Fibrous Roots
Root
Hairs
STRUCTURE
OF ROOTS
1.Root Hairs:
increase surface
area for water &
mineral
absorption
2.Meristem:
region where
new cells are
produced
3.Root Cap:
protects tip of
growing root
Meristem
Root
Cap
QUIZ TIME! BEFORE WE CONTINUE…
VASCULAR OR NON-VASCULAR?
“Naked seeds” are not
enclosed in an ovule (like a
pine cone).
Gymnosperms
Plants are usually evergreens.
Ex. pines, cedars, spruces and
firs.
VASCULAR PLANTS
Mature seed is surrounded by
the ovule (think of an apple).
Contain a vascular system
allowing for transportation
of nutrients / water
throughout the plant
Angiosperms
Angiosperms are trees/plants
that shed leaves every
autumn.
Ex. Oaks, maples and
dogwoods are examples of
deciduous trees.
http://dendro.cnre.vt.edu/forsite/idtype.htm
QUIZ TIME! BEFORE WE CONTINUE…
GYMNOSPERM OR ANGIOSPERM ?
KEY WORDS: PLANT
BIOLOGY
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Cell wall
Chloroplast
Vascular tissue
Non-vascular tissue
Stomata
Cuticle
Veins
Mesophyll
Chlorplast
Guard cell
Stomata
Transpiration
Root hair
Meristem
Root cap
Gymnosperm