plant cell organisation

• Plants are made of organs like

  stems, roots, leaves
• Plant organs work together to make

  organ systems
• What covers the entire plant

  The epidermal tissue
• What are the layers of a plant

  -waxy cuticle

  -upper epidermis

  -palisade mesophyll

  -Spongy mesophyll

  -lower epidermis
• The waxy cuticle is a

  Thin layer of lipids
• The waxy cuticle forms a

  waterproof layer to minimise water loss
• The upper epidermis is

  Transparent so light can pass through it to reach the palisade layer
• This means that they're near the_____ of the leaf where they can get the______light

  This means that they are near the top of the leaf where they can get the most light
• What happens at the Palisade mesophyll tissue

  Most of the photosynthesis of the plant
• The palisade mesophyll contains

  lots of chloroplasts for photosynthesis
• What does spongy mesophyll tissue contain?

  Big air spaces to allow gases to diffuse in and out of cells
• The air spaces in the spongy mesophyll tissue increase the

  Rate of diffusion of gases
• What is the xylem's function?

  to transport water and small nutrients up the plant to the leafs from the roots
• What is phloem's function?

  to transport glucose and large molecules up and down the plant
• The xylem and phloem form a_____which deliver_____ and other nutrients to the entire leaf and take away the______ produced by photosynthesis

  The xylem and phloem form a network which deliver water and other nutrients to the entire leaf and take away the glucose produced by photosynthesis
• The lower epidermis is full of little holes called

  stomata
• What does the stomata diffuse in

  Carbon dioxide
• What does the stomata diffuse out

  Water vapour
• The opening and closing of the stomata is controlled by

  guard cells in response to environmental conditions
• What do guard cells have that allows them to open and close the stomata

  -a kidney shape

  -thin outer walls and thickened inner walls
• When the plant has lots of water

  -guard cells fill + well hydrated + turgid

  -makes stomata open so gases can be exchanged for photosynthesis

  -water vapour is diffused out
• When the plant is short of water

  -guard cells lose water + become flaccid making stomata close

  -helps to minimise water vapour escaping
• At night the guard cells

  close the pores to prevent unnecessary water loss as photosynthesis isn't taking place therefore they don't need CO2
• Why are the somata on the lower side of the leaf

  -it is more shaded making it cooler therefore less water will evaporate
• Therefore the guard cells are adapted for

  Gas exchange and controlling water loss within a leaf
• The meristem tissue is found at the

  Growing tips of shoots and roots
• What is meristem tissue able to do

  Differentiate into lots of different types of plant cell allowing the plant to grow
• What are the characteristics of meristem tissue?

  -they are undifferentiated cells

  -they are living and thin walled

  -They are made up of immature cells
• The leaf is an____made up of several types of_____

  The leaf is an organ made up of several types of tissue