Download - Lesson 4 : Roots, water and minerals
Lesson 4 : Roots, water and minerals
Lesson aims
•To study the uptake and movement of water in plants, looking at root structure, path through plant and importance of minerals.
Lesson outcomesBy the end of the lesson pupils should • be able to describe how substances from
soil enter and move through a plant• describe how these substances are used• be able to describe how roots are
adapted to take in water• know root cells require oxygen for
respiration from air in soil
Plant growthPlant growth
Plants grow using food they make through photosynthesis. So what else do they need?
Plants also need three important minerals to keep healthy. They absorb these through their roots.
Roots The roots of a plant provide:• A way of getting water from the ground.• Stability for the plant by anchoring it into the ground.
The water absorbed by the plant is used for:• Photosynthesis.• Keeping the plant rigid (turgidity)• All the chemical reactions in the plant• To move dissolved minerals (nitrates) to cells
The passage of water through plants Draw diagrams to describe your
observations and answer these questions
1. Roots How do the roots get a large surface area ? Why
is this helpful?2. Stem How does water and nutrients travel from the
roots to the leaves 3. Leaves How can water escape form leaves?
Spectrum Biology P.134-137 may help
A
B
C
D E
Root hair cells
Plant roots are made of “root hair cells” which have a large surface area and a thin cell membrane to help absorb the minerals, water and oxygen:
Thin cell membrane
Large surface area
1.Why do you think plants take in
oxygen throughtheir roots?
2. Why do plants take in mineralsthrough their
roots?
The three main types of nutrient are:The three main types of nutrient are:1. Nitrogen in the form Nitrates –
used to make proteins2. Phosphorus in the form of
Phosphates – used to provide phosphorus to help photosynthesis and respiration
3. Potassium – helps the enzymes that are needed for photosynthesis and respiration
Lack of the three minerals would lead to a “Deficiency Symptom”:
Lack of nitrates:Small plant, yellow leaves
Lack of phosphates:Small roots and purple leaves
Lack of potassium:Yellow leaves with dead bits
Can you?Describe how substances from soil enter
and move through a plantDescribe how roots are adapted to take in
water
Why do root cells require oxygen from air in soil?
Can you describe how plants use water?
Do you know why plants need minerals?
- branched, root hairs, large surface area
photosynthesis, transport minerals, for cell growth, form fruits, cool leaves
HomeworkDraw a poster showing every thing
you know about plants (include why plants need phosphates, nitrates and potassium and happens to a plant if it suffers from a deficiency of each nutrient)