Transcript Root Adaptation - Noadswood Science

D. Crowley, 2008
To know how roots are adapted for absorption
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Look at the following, and decide if the statements are true or false…
1. New material in plants is called biomass True
2. Plants use soil and water to make new biomass via respiration False - photo.
3. Sound energy is needed for photosynthesis to occur False - light
4. Photosynthesis produces glucose and carbon dioxide False – oxygen
5. Photosynthesis happens mainly in the palisade cells within the roots False leaves
6. Palisade cells are adapted to their function by having lots of
chloroplasts True
7. Plants use glucose to make cellulose, fats, proteins and starch True
8. Roots take in water and minerals True
9. Roots are adapted to take in water by having a small surface area False large
10. Water travels up the plant in xylem tubes True
11. Plants need carbon dioxide to make glucose True
12. Plants are important in making carbon dioxide to keep the
atmosphere in balance False – oxygen produced to balance atmosphere
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What are the functions of roots?
• Absorb water
• Absorb minerals
• Anchorage (hold the plant to the ground)
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Look at the samples of root under the microscope – how are they
adapted for absorption?
Water and minerals are absorbed from the soil via the roots
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The roots are covered with millions of tiny
root hair cells
These have a very large surface area,
allowing the roots to absorb large amounts
of water and minerals
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water
Roots are spread out, helping both
absorption of water and minerals and with
anchorage…
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Why do plants need water?
• Plants need water for photosynthesis to take place
6CO2 + 6H2O  C6H12O6 + 6O2
• Helps with transport around the plant
• Helps the plant stay rigid and upright
• Allows the plant to keep cool
(transpiration is the loss of water from
the plant, as water evaporates from the
leaves (which draws up water + minerals
from the roots))
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Plant roots are also adapted to absorb minerals from the soil
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There are three essential minerals plants need to stay healthy: • Nitrates – for protein manufacture
• Phosphates – for photosynthesis and respiration
• Potassium – for photosynthesis and respiration
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A lack of minerals can cause major problems for a plant: -
• A lack of nitrate can cause stunted growth
and yellowing of older leaves
• A lack of phosphate can cause poor root
growth and purple younger leaves
• A lack of potassium can cause yellow
leaves with dead spots on them
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Roots provide stability for the plant, keeping it fixed to the soil
which is needed, especially when it is windy
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Xylem tubes carry water and
minerals up the plant via the
transpiration stream
They have strong side walls
made of lignin, giving the plant
support
They are made of dead cells
with no ends between them
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Phloem tubes transport food
up and down the plant
They carry sugars; fats;
proteins etc… to growing
regions / storage regions in
the plant
They are made of living cells