plant tissues 2.3.1

• both animal and plant cells have ribosomes, cell membranes, nucleus, cytoplasm and mitochondria
• only a plant cell has chloroplasts
• only a plant cell has a cellulose cell wall
• only a plant cell has a vacuole
• the upper epidermis covers the surfaces and protects them and secrete a waxy substance that waterproofs the leaf
• the palisade mesophyll contains chloroplasts for photosynthesis
• the spongy mesophyll contains some chloroplasts and has big air spaces and a large surface area for easier diffusion of gases
• the xylem transports water and minerals from the roots to the leaves
• the phloem transport sugars from the leaves to the rest of the plant
• the lower epidermis contains guard cells and stomata
• the guard cells open and close the stomata
• the stomata are pores to allow gas exchange in leaves
• the meristem tissues are found at growing tips of roots and shoots, and between xylem/ phloem vessels, it contains rapidly dividing plant cells that grow and differentiate into all the other cell types needed
• the palisade mesophyll tissue is composed of many specialised palisade cells that work together yo carry out photosynthesis, so it is a tissue
• a leaf comprises of many different tissues (eg vascular tissue, phloem tissue, xylem tissue, palisade and spongy mesophyll tissue etc) that work together to carry out photosynthesis and so a leaf is considered an organ
• mitosis takes place in meristem tissue
• the leaves carry out photosynthesis
• the stem supports the leaves and flowers and also transports
• the roots absorb water and minerals from soil and also anchors the plant to the ground
• the flowers are used for sexual reproduction