b4

• Photosynthesis is a chemical process used by plants to make glucose and oxygen from carbon dioxide and water, using light energy.
• Oxygen is produced as a by-product of photosynthesis.
• Algae subsumed within plants and some bacteria are also photosynthetic.
• During photosynthesis, plants produce glucose, a simple sugar used by cells for respiration.
• The food that plants produce is important, not only for the plants themselves, but for the other organisms that feed on the plants.
• Photosynthesis requires energy in the form of light to drive the chemical reaction.
• Photosynthesis is an endothermic reaction in which energy is taken in.
• The light energy required for photosynthesis is absorbed by a green pigment called chlorophyll, which is the green chemical inside the chloroplasts of plant cells.
• During the day, provided the rate of photosynthesis is sufficiently high, plant leaves, and water plants, give out oxygen.
• The palisade mesophyll is a type of plant tissue containing closely packed cells in the upper layer of a leaf.
• Leaves are the main photosynthetic organ in plants, but any part of the plant exposed to the light will develop chlorophyll and photosynthesise.
• Some of the glucose produced by photosynthesis is used for respiration, which is the chemical change that takes place inside living cells, which uses glucose and oxygen to release the energy that organisms need to live.
• The carbon dioxide required for photosynthesis comes from the air and enters leaves through the stomata, which are tiny holes in the epidermis (skin) of a leaf that control gas exchange by opening and closing and are involved in loss of water from leaves.
• The spongy mesophyll is a type of plant tissue in a leaf which has loosely packed cells and air spaces between them to allow gas exchange.
• Chlorophyll is located in chloroplasts close to the cell membrane and contains the green pigment chlorophyll, the site of photosynthesis.
• Water enters the plant through the roots, and is transported to the leaves in the xylem, which are narrow, hollow, dead tubes with lignin, responsible for the transport of water and minerals in plants.
• Glucose is the starting point for the biosynthesis of materials that plants need to live.
• Oxygen is formed as the waste product of photosynthesis and some is used for the plant's respiration, while the rest is released which makes it available for respiration to animals and many microorganisms.
• Plant cells are the basic unit of life and can be found in both unicellular organisms and multicellular organisms.
• The glucose not used for respiration is used in the following ways: respiration, biosynthesis, and glucose storage.
• Carbon dioxide is a by-product of respiration.
• Cellular respiration is a process that all organisms undergo in order to release energy to fuel their living processes.
• Respiration can be aerobic, which uses glucose and oxygen, or anaerobic which uses only glucose.
• Anaerobic respiration is the response to exercise.
• Oxygen debt and the liver are topics related to anaerobic respiration.
• Metabolism is the process of cellular respiration, which releases energy.
• Respiration releases energy, making it an exothermic process.
• A reaction in which energy is given out to the surroundings is exothermic.
• Photosynthesis is the process by which plants, and some bacteria, synthesise food molecules, which they then use, in addition to other things, for respiration.
• The process of photosynthesis requires energy, making it endothermic.
• Don't confuse respiration with photosynthesis, as they are different processes.
• Respiration happens in cells.
• All organisms need energy to live, which is used to drive the chemical reactions needed to keep organisms alive and to build complex carbohydrates.
• Carbohydrates are vital for energy in humans and are stored as fat if eaten in excess.
• In plants, carbohydrates are important for photosynthesis.
• Energy is also used for cell division to maintain constant conditions in cells and the body, a process known as homeostasis.
• Photosynthesis is a chemical process used by plants to make glucose and oxygen from carbon dioxide and water, using light energy.
• In birds and mammals, this heat is distributed around the body by the blood, keeping these animals warm and helping to maintain a constant internal temperature.
• In animals, energy is needed to make muscles contract, while in plants, it is needed for transport of substances in the phloem.
• Algae subsumed within plants and some bacteria are also photosynthetic.