Root hair cells

Plants and animals have stem cells.

These are cells that have not undergone changes to become specialised cells.

Which process do stem cells go through to become specialised cells?

Tick (✓) one box.

The table gives features of different types of stem cells.

Complete the table by putting one tick (✓) in each row.

One type of specialised cell in a plant is a root hair cell, shown in the diagram.

Give a function of a root hair cell and state how it is adapted for that function.

One role of a root hair cell is to move ions into the plant against the concentration gradient.

State the name given to this type of transport.

The photograph shows a cross section of a root seen under a light microscope.

Transport cell

Complete each sentence about root hair cells. Use words from the list.

active transport glucose
mineral ions

osmosis
surface area
volume

Root hair cells take in water and........ from the soil.

Water is taken in by the process of........

For more efficient uptake, the root hair cell has a large........

Water moves from the root hair cells into the transport cells of the roots.

Describe how water travels to the leaves of the plant from the roots.

A student investigates the effect of air movement on the rate of water uptake using a plant cutting.

The diagram shows the apparatus they use.

Electric fan

This is the method they follow:

• Measure the level of water in the calibrated pipette.

• Switch on the fan and record the level of water again after 25 minutes.

• Repeat investigation with the fan switched off.

The table shows their results.

Describe the effect of air movement on water uptake.

Calculate the rate of water uptake when the fan is switched off.

Give your answer to 1 significant figure.

Rate of water uptake =........ cm³ / min

Suggest one way the student could now investigate the effect of light intensity on water uptake.

The photograph shows a cross section of a root seen with a light microscope.

The function of cell Q in the photograph is the uptake of water.

Explain how the structure of cell Q is adapted to this function.

Explain how the water moves through the root from cell Q to the xylem. Include ideas about water potential.

Explain the effect of turning on the electric fan upon the rate of water uptake shown in the table.

Suggest how the student could develop their investigation to explore the effect of changing the speed of air movement.

Why do root hair cells require large numbers of mitochondria?

A For the uptake of minerals by active transport.

B For the uptake of water by active transport.

C For the uptake of minerals by osmosis.

D For the uptake of water by osmosis.

The diagram shows cells from a plant.

What is the function of these cells?

A Produce sucrose

B Take in water from the soil

C Transport sucrose to the roots

D Transport water up the stem

Surface area is important for transport in plants.

Scientists investigate the relationship between surface area and volume.

Roots are important for transport in plants.

The diagram in Fig. 12.2 shows a root tip, with a root hair cell labelled.

The root hair cell is adapted for its function.

Explain why the adaptation is needed.

Look at the area of the root tip labelled X in Fig. 12.2.

Describe the type and function of the cells found in area X.

The picture shows plant cells as seen using a light microscope.

Draw a large labelled diagram of cell X.

The plant cells shown in Fig. 11.1 are not root cells.

Explain how you can tell this from the picture.

A plant is growing in a soil of pH 4.

Which mineral ion will be most available to the plant?

Magnesium is required by plants for photosynthesis.

Growing plants in very alkaline soils may result in less biomass.

Use the chart to explain why.

The picture shows a root growing from a seed.

Explain how the structures seen on the root help with the uptake of minerals.