Plant Structure

Root Hair Cell

Plants are able to absorb water through__ osmosis__, and absorb mineral ions through active transport.

Root hair cells__ __are adapted so that they can carry out these functions.

  1. Root hair cells are long and thin, which gives them a large surface area in order to increase the rate of absorption.
  2. They contain mitochondria which is needed for active transport as it moves the minerals against the concentration gradient. Mitochondria releases energy from the glucose during respiration so that it can provide the energy that is required for active transport.

Plant Structure, figure 1

Xylem

The xylem is a plant tissue that is vital for the plant as it transports_ water and minerals__ from the roots to the plant’s stem and leaves_.

Part of the Xylem is made of dead cells. They do not have an end wall as the xylem is a continuous hollow tube. Lignin can be found in their walls as it strengthens the plant.

The transportation of water and minerals does not require any energy.

Phloem

The phloem__ is also an important plant tissue as it moves food substances (sucrose__) that were produced through photosynthesis towards growing parts of the plant, storage organs (bulbs and tubers) and developing seeds.

The substances that transport throughout the phloem will travel both up and down the stem as there are so many different parts of the plant that require the food.

Plant Structure, figure 1

Translocation

Translocation is the name of the process when sugars are transported in the phloem. This is an active process.

  1. Phloem contains living cells, and its structure is made of sieve tubes and companion cells.
  2. Sieve tubes are needed for transport, and have no nuclei.
  3. Companion cells are attached to sieve tubes in order to provide energy for translocation.
  4. Sieve tubes and companion cells must work together in order for translocation to be successful.

Structure of the Leaf

Plant Structure, figure 1

Plant Structure, figure 2

Through which process do root hair cells absorb water?
Osmosis
What is the advantage in having a transparent epidermis?
Your answer should include: Light / Chlorophyll / Absorbed / Photosynthesis
Explanation: Allows light to get through to the chlorophyll so that light can be absorbed for photosynthesis
What is translocation?
Your answer should include: Sugars / Transport / Transported / Phloem
Explanation: Process when sugars are transported in the phloem