Download Structure of Plants

The
Structure
of Plants
ROOTS
FUNCTION OF ROOTS
1. Anchor and support the plant in the ground. (stability)
2. Absorb water and nutrients from the earth.
3. Transport water and nutrients to the stem.
4. Hold soil in place. Prevents soil erosion.
ROOT TYPES
• there are two basic root types
1. Fibrous roots
• These branching roots help
hold soil in place and
prevent erosion
• Quick absorption
• Ex: grasses
2. Taproots
• Large central root that
reaches deep water
sources
• Very strong anchor
• Ex: trees, carrots,
dandelions
CAN YOU IDENTIFY THESE ROOTS?
DID YOU KNOW THAT YOU PROBABLY
EAT ROOTS?
ROOT STRUCTURE
1. Root Hairs
• Increase surface area of absorption
2. Meristem
• New cells are produced here and the root grows
3. Root Cap
• Protects the growing root
DIFFUSION and OSMOSIS
• Two key processes that allow roots to absorb water and nutrients
1. Diffusion
• Based on equilibrium
• Particles/substances move from areas of greater
concentration to areas of lower concentration
2. Osmosis
• Osmosis is a type of diffusion
• It is the diffusion of water through a differentially permeable
cell membrane.
Only allows certain particles to pass into the cells.
STEMS
STEM FUNCTION
• stem serve 3 basic function for plants
1. Transportation
• Transports water and nutrients between the roots and
leaves
2. Structure
• Supports leaves, fruit and flowers.
3. Storage
• Some stems act as cupboards or refrigerators
• Ex: a potato is an under ground stem known as a tuber
STEM STRUCTURE
Xylem
• carries water and
minerals to the parts of
the plant
• acts as supports
Phloem
• carries food
(sugars/starches) to
parts of the plant
LEAVES
FUNCTION OF LEAVES
1. Photosynthesis
• Plants convert radiant energy from the sun into chemical
energy in the form of glucose (sugar)
• Process that plants use to produce their food
WATER + CARBON DIOXIDE + SUNLIGHT = GLUCUSE + OXYGEN
SO HOW DO PLANTS GIVE US OXYGEN?
It takes place due to a chemical reaction….
hydrogen
carbon
oxygen
Glucose’s chemical make-up is C6H12O6 …..so how do we get this from
water, carbon dioxide and sunlight ????????
Here’s how…
We need 6 molecules of CO2 (carbon dioxide) and 6 molecules of H2O
(water) in order to make glucose.
How many carbon molecules is that? Hydrogen? Oxygen?
Wait a sec….did you say 18 oxygen molecules??? But we only need
6 molecules to make the glucose in plants. What happens to the extra
oxygen molecules?
BINGO!!!
We get AIR !!! (oxygen)
This what the complete chemical equation looks like….
6CO2 + 6H2O C6H12O6 + 6O2
This becomes our
oxygen from plants!!
FUNCTION OF LEAVES
2. Transpiration
• Ensures water moves through the plant
• Controlled by the moisture content in the air and soil,
temperature, and wind
• Water regulation and exchange of carbon dioxide controlled
by stomata
WAIT A SEC!!!!!!!!!!
What the heck is a
stomata?
THIS IS A
STOMATA!!!!!!
FUNCTION OF LEAVES
• Stomata function as the gate keepers of the plant
• They are located in the leaves and control the movement of water
and gases (H2O, O2 and CO2)
Guard cells depend on
osmosis to work.
When they take in
water, they open the
stomata. They are
open during the
daytime.
When guard
cells lose water
they close the
stomata. They
are closed at
night.
FLOWERS
FUNCTION OF FLOWERS
Sexual Reproduction!!!!
So why are flowers so brightly colored??
FUNCTION OF FLOWERS
• Flowers are pollinated by:
– Wind
– Insects
– Birds
– Animals
SEEDS
PARTS OF THE SEED
• Embryo
– Growing part of seed containing:
• Leaf
(the hypocotyl)
• Stem
• Root (the radical)
• Cotyledon
– provides nutrition (food) for the
developing seed
• Seed Coat
– Protective outer covering of the
seed
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KeEbE&safe=active