Plant Cellular Processes

evolved morphological, anatomical and physiological adaptations to obtain, process, transport and store raw materials and energy under varying conditions. capture and conversion of radiant energy to chemical energy takes place in chloroplasts (chloroplasts are localized in specialized tissues) products of photosynthesis are used in respiration, growth, repair, maintenance, storage. energy consuming reactions must take place for the substances of photosynthesis to be transported around the plant. energy is supplied to plant cells through respiration movement of substances occurs by diffusion, osmosis and active transport. Water and mineral ions must be supplied and conserved in the plant. cell wall makes plants have no mobility cell wall bring turgor pressure. Turgor pressure increased in ‘woody plants’ - with lignin. photosynthesis - is the process whereby radiant energy from the sun is converted to the chemical bond energy of glucose. It occurs in chloroplasts within specialised cells. chlorophyll- convert light energy to the chemical bond energy of ATP energy to transform carbon dioxide and hydrogen (from water) to glucose is provided by this ATP oxygen is given off as a waste product sunlight carbon dioxide + water ➞ glucose + oxygen chlorophyll 6CO2 + 6H2O ➞ C6H12O6 + 6O2
LEAF STRUCTURE: broad flat part - the lamina petiole/stem - joins the lamina to the plant xylem - running through the petiole - transport water and mineral ions from the roots phloem - transporting sugars and other small organic molecules to different parts of the plant. epidermis - function is to protect the inner layers of cells - is a close fitting layer on both the top and bottom of the leaf. epidermal cells sometimes secrete a waxy cuticle - reduces evaporation from cells. lower epidermis there are stomata each stoma is surrounded by guard cells - can open/close the space between them. guard cells contain chloroplasts / epidermal cells do not contain