1. Why is nutrition important for a living organism?
2. How do green plants synthesise their food?
3. State the role of vessels' present in a plant
4 Define the following terms:
(a) Symbiotic relationship
(b) Nutrients
(c) Saprotrophic mode of nutrition
(d) Photosynthesis
5. When some wheat dough was left in the open for a few days, i
please tell the answer
a foul smell. State, why?
Answers
1) All activities such as playing, running, walking, studying, etc. require energy. The various nutrients present in our food such as carbohydrates, proteins, fats, vitamins, and minerals provide energy to our body making our brain and body cells nutritious (or, nutritive). Nutrition is important for the overall growth and development of the body.
2) The green plants synthesize their food by a process called PHOTOSYNTHESIS. Photosynthesis is the physico-chemical process by which plants can convert light energy into chemical energy, in the form of food using atmospheric carbon dioxide and water as raw materials.
3) Vessels form an efficient system for transporting water (including necessary minerals) from the root to the leaves and other parts of the plant. Vessels are an integral part of xylem which are mainly involved in the conduction of sap. These are typically found in flowering plants (angiosperms) but absent from most gymnosperms, such as conifers.
4) (a) A symbiotic relationship is an evolved interaction or close living relationship between organisms from different species, usually with benefits to one or both of the individuals involved. By symbiotic relationship, two or more organisms get mutually dependent on each other for food, water and shelter.
(b) The components of food required by our body for its growth and proper functioning are called nutrients. They are - carbohydrates,vitamins, fats, minerals.
(c) The mode of nutrition in the organisms that have grow on dead and decaying matters is known as saprotrophic mode of nutrition.
(d) Plants synthesise their own food from carbondioxide and water in presence of chlorophyll and sunlight. This is process is called photosynthesis.
5) When the wheat dough is kept in open for few days, the formation of fungus and reproduction of yeast takes place. These fungi and yeast will become unfit for eating or for use. Since the formation of fungus takes place in the dough, it gives a foul smell.