B4.6 Tissues and organs in plants Flashcards
What is the epidermal tissue?
Covers the surface of the leaf and protects them - often secrete a waxy substance that waterproofs the surface of the leaf
What is the palisade mesophyll?
A tissue that contains a lot of chloroplasts which carry out photosynthesis
What is the spongy mesophyll?
Tissue containing some chloroplasts for photosynthesis but also has big air spaces and a large surface area to make diffusion of gases easier
What does the xylem carry?
Water and mineral ions from the roots up to the leaves
What does the phloem carry?
Dissolved food from the leaves around the plant
What is the meristem tissue?
It is at the growing tips of roots and shoots and is made up of rapidly dividing plant cells that grow and differentiate into all the other cell types needed
What does the leaf do?
Carry out photsynthesis
What does the stem do?
Supports leaves and flowers
What is the structure of a plant?
Upper epidermis
Palisade mesophyll
Spongy mesophyll
Lower epidermis
What is the purpose of the big surface area in the spongy mesophyll?
Greater increase in gas exchange
What is the purpose of the stomata?
Allows gases to move in and out of the leaf
What is the purpose of the guard cells?
Control the opening and closing of the stomata
