UNIT 4 | Science stage 9

Maintaining life

4.1 Plants and Water

Find out how plants absorb water

Discover how water moves from plant`s roots to its leaves

• ​Water enters through root hair cells (tiny hairs) which provides large surface area.

• Water moves from cell to cell

How root hair cells absorb water

• In the centre of the root the water enters the xylem vessels - vein-like tissues that transport water and minerals up a plant.​

​Xylem in roots and stems

Multiple Choice

transport water and minerals to the cells of the leaf(water)

• mesophyll

• xylem

• phloem

• chloroplast

Multiple Choice

Xylem tissue is important because it

• can conduct water over long distances.

• allows water to diffuse from the roots.

• carries carbohydrates to all parts of the plant.

• carries out photosynthesis.

Multiple Choice

Which of the following makes up a molecule of water?

• one atom of hydrogen and one atom of oxygen

• one atom of sodium and one atom of chlorine

• one atom of hydrogen and two atoms of oxygen

• two atoms of hydrogen and one atom of oxygen

Multiple Choice

Which part of the plant absorbs water and nutrients from the soil?

• root nodules

• root hair

• root cortex

Open Ended

What happens to the excess water in plants?

• Find out how water vapor lost from plant leaves
  
  Summarize why plant needs water

​Some of the water evaporates into the surrounding air spaces inside the leaf and then diffuses out through the stomata into the surrounding air.

Water moves from the xylem vessels into the mesophyll cells where it can be used for photosynthesis.

Water in leaves

The rate of transpiration is affected by wind speed, humidity, temperature and surface area.

https://www.youtube.com/watch?v=bvPM6sfidY4

Plants need water for

Support - to avoid wilting

Transport - minerals

Cooling - good in hot weather

Photosynthesis - to make glucose

Multiple Choice

Transpiration a part of?

• Life Cycle

• Water Cycle

• Carbon Cycle

• Phosphorus Cycle

Multiple Choice

What is absorbed by the plant by it's roots, and transpiration takes place as the water exits the ________?

• Leaves

• Stem

• Branch

• Roots

Multiple Choice

Transpiration is a part of____________?

• Condensation

• Sublimation

• Evaporation

• Precipitation

Multiple Choice

What is the effect of increasing light intensity in transpiration?

• It decreases transpiration rates

• It increases transpiration rates

• It doesn't impact the rate of transpiration

Multiple Choice

Which of the following indicates the pathway of water through a plant?

• Stomata=>Root hair cell=>Xylem

• Root hair cell=>Xylem=>Stomata

• Xylem=>Stomata=>Root hair cell

Multiple Choice

Which is true?

• 99% of water taken by the plant evaporates through transpiration

• 9% of water taken by the plant evaporates through transpiration

• Evaporation through transpiration accounts only for 1% of all the water the plant takes in

• Evaporation through transpiration is minuscule

Multiple Choice

Stomata opens during night and closes during day

• True

• False

Multiple Select

Factors which affect transpiration are (external)

• Sunlight

• Wind speed

• Humidity

• Rain

Multiple Select

What is significance of transpiration

• Creates suction force

• Helps in distribution of water and nutrients

• Cooling effect for plants

• All of the above

Multiple Choice

Stomata opens up only for the intake of CO2

• True

• False

Multiple Choice

What is the purpose of the XYLEM?

• To bring food from the soil to the whole plant.

• To carry water and nutrients from the roots to the whole plant.

• To carry food from the chloroplasts around to all parts of the plant.

Multiple Choice

If plants don't store up water, how does water leave the plant?

• The roots get rid of excess water.

• Most plants DO store water.

• It is released from the leaves by TRANSPIRATION.