GCSE Plant Organisation Key Words

Epidermal tissue

Covers the surface of the leaf and protects it. Secretes a waxy substance that waterproofs the surface of the leaf.

Palisade tissue

Contains lots of chloroplasts which carry out photosynthesis.

Spongy mesophyll tissue

Tissue in the leaf that contains some chloroplasts but also has big air spaces and a large surface area to make diffusion of gases easier.

Xylem tissue

Transports water and mineral ions from the roots to the stems and leaves.

Phloem tissue

Transports dissolved sugars from the leaves to the rest of the plant.

Stomata

Openings in the leaves of plants which allow gases to enter and leave the leaf.

Guard cells

Cells that surround the stomata and control their opening and closing.

Translocation

Movement of dissolved sugars from the leaves to the rest of the plant through the phloem.

Transpiration

The loss of water vapour from the leaves of plants through the stomata. It involves evaporation from the surface of the cells and diffusion through the stomata.

osmosis

The diffusion of water from a dilute solution to a concentrated solution through a partially permeable membrane.

Active transport

The movement of substances from a dilute solution to a more concentrated solution against a concentration gradient requiring energy from respiration.

Potometer

A piece of apparatus that can be used to measure the rate of transpiration.

Photosynthesis

The process by which plants make food Water + carbon dioxide🡪 glucose +oxygen