Transcript to the Unit 2 Topic 1/2 PowerPoint

Plants &
People
How we all connect
together …
People & Plants
 How



do humans use plants?
Food
Fibre (building materials)
Medicines
 Plants
are vital to our survival!
Plants & Ecosystems
 We
know for humans … but for the
environment?
 Plants
filter our air
(Breath in what we breath out)
 Plants help filter our water
(Clean up dirty water)
 Plants help keep soil in place
(Roots hold earth together)
Plants & Food
 Mind
– blowing fact …
75% of the world’s food supply is based on
seven major crops …
- wheat
- potatoes
- rice
- corn
- barley
- sorghum
- cassava
Plants & Fibre
 While
many things are manufactured …
we still use 3 natural fibres!
-
Cotton
- Flax
- Hemp
Cotton
 (Currently)
The
world’s most
important nonedible plant!
 Their
structure (strong, flexible, gradual
spiral) makes them extremely versatile!
Hemp
 Oldest
cultivated
plant in the world!
 Less
negative effect than other fibres
 Hemp




Factoids!
Hemp paper lasts longer than wood pulp paper
Ready for harvest in 1 year
First Bible printed on hemp paper
Nothing eats it so no pesticides required!
Flax
 Grows
in nothern,
cooler regions
 Fibres in stems is 2 to
3x stronger than
cotton
 Used in a variety of
different process (oil paints and varnish)
Plants & Medicines
 Before
over the counter medicine existed
people used the plants around them


Ginger = upset stomach
Bark of white willow = pain killer
 How
Aspeirin was developed
 Hundreds
of examples exists like
Morphine, Codeine, etc …
Plants & Transportation
 Rubber
(latex) changed our world
 Comes from Brazilian Rubber Tree
(Only source in the world)
 Synthetic exists but not as good
Plants & Fuel
 Wood
burned for fuel
 Old plants provide fuel






Died
Buried
Compressed
Structural / Chemical Changes
Became Coal
Burn Coal for Fuel
Plant Life – Roots
 Plants
are like icebergs, they work like this …
Plant Life – Roots
 What



do they do?
Absorb minerals / water
Anchor / support plant
Store food
Root Crops
• You eat root vegetables
you are eating a root!
• WHOA!
Diffusion & Osmosis
 Diffusion

is key for plant roots
Moving and distributing evenly from areas
of higher concentrations to lower
concentration
Diffusion & Osmosis
 Diffusion

is key for plant roots
Moving and distributing evenly from areas
of higher concentrations to lower
concentration
Osmosis
 Diffusion
of water through a differentially
permeable membrane

(Like a mesh bag with sand and marbles …
the sand can go through but not the
marbles)
 Cells

in roots are differentially permeable
(Allow some things such as water & nutrients
and hold the rest out)
Stems
 Refer
I
to page 108 in your text book.
would know that diagram of a tree trunk
and the layers *hint*
Stems Cont …
 Support

They provide support for leaves so they get
enough sunlight to make food
 Some
are tiny (few mm) and some are
huge (100+m long)
Stems Cont …
 Food

Storage
They store food produced by the leaves
 Underground
vegetables (i.e.: potatoe)
have tubers which store food in the form
of starch for the potatoes to use
 Factoid!

The barrel cactus does this so well it can last
a year without water
Leaves
 Leaves
turn green due to chlorophyll
 Leaves use the sun to make food turning
the light into chemical energy
 But
how…?
 They


need to ingredients
Water
Carbon Dioxide
Leaves Cont …
 Water
+ Cardon Dioxide = Sugar
 This is the plants energy storing chemical
 The
process is known as photosynthesis!
Video Explanation!
Stoma/Stomata
 Open
during day
 Close at night
 Carbon Dioxide
enters and goes into
chloroplasts
 Reaction occurs that
produces sugar and
oxygen
Leaves Cont …
Simple Video
 The
sugar feeds the plant
 The oxygen is released
 Plant need oxygen too!

At night, when no sunlight is around, plants
release CO2 and absorb Oxygen
 This



is done through guard cells (via osmosis
Swell with water = open & release of CO2 &
water vapour
Lose water = closed
This is transperation (i.e.: how water moves up)
Moving Water
 Roots
are pulling water in and it is going up
via root hairs and osmosis
 Leaves are pulling water from xylem as well
 Powerful
stuff!