Plant Structures and Processes PDF

Learning Pack for Plants for Food and Fibre – Unit 2 (Science In Action 7) 4 1.0 Understanding structures and life processes of plants helps us to interpret their needs. 1.1 The Body of Seed Plants Seed plants are the largest group of plants in the world. Each seed plant structure ha...

Learning Pack for Plants for Food and Fibre – Unit 2 (Science In Action 7) 4 1.0 Understanding structures and life processes of plants helps us to interpret their needs. 1.1 The Body of Seed Plants Seed plants are the largest group of plants in the world. Each seed plant structure has specific functions. 1.2 Plant Processes A Process For Moving Water Up From The Roots A combination of different processes moves the water from the roots to other parts of the plant, and also allows substances in and out of the cells. Osmosis is a particular type of diffusion in which only some of the particles are allowed to pass through a barrier. This barrier is called a differentially permeable membrane. Osmosis is the diffusion of water through a differentially permeable membrane. Capillary action – where the water particles are attracted to each other and to the sides of the tubes, and the pushing and pulling action of diffusion and osmosis (moving water through the xylem tissue in the stem) moves water from the roots up to the very top of the plant. The loss of water through evaporation is called transpiration. Active Transport is another process that enables a plant to get nutrients regardless of the difference in concentration. It does however require energy to move these substances in and out of the plant. A Process to Make Food A pigment called chlorophyll makes the leaves green. The energy of the sun is trapped in the leaves and changed into a kind of chemical energy. Carbon dioxide and water are used by the leaves in the process called photosynthesis, to make sugar and give off oxygen. Plants also need oxygen - at night when photosynthesis does not happen, respiration does. A Process to Use Food Cellular Respiration is a gas exchange process by which plants release carbon dioxide and let oxygen into their cells. Water enters and leaves the cells in the leaves through the guard cells. When they absorb water they swell, opening the stoma (which lets in carbon dioxide and lets out water vapor). The word equation for cellular respiration is: Sugar + Oxygen Æ Carbon Dioxide + Water + Energy Copyright 2005 – Developed by Edquest Resources (www.edquest.ca)