question_answer

  What happens to food inside small intestine? How do intestinal walls facilitate food absorption? Or Shanu told his father that plant exude out alot of water in vapour form from leaves, define it. What is its importance? How do stomata help in this process?

Answer:

  The food digestion is completed in small intestine. Duodenum brings semi-digested food, which receives bile juices (from liver) and pancreatic juices (from pancreas). The fat is emulsified by bile juices. Proteins, fats and carbohydrates are digested byenzyme of pancreatic juice.                                                                                           (2) (a) Trypsin acts on proteins to form peptides. (b) Lipase acts on fats to form fatty acids and glycerol. (c) Amylase acts on starch to form sugars. The intestinal walls have small projections called villi. Each villus is richly supplied by blood vessels. The villi increase the surface area of the intestinal walls to help in absorption of absorbed food. The success sentericus juice completes the digestion process and food is absorbed to reachall cells of the body by villi walls.                                                                                                                                                                             (1) Or This process is called transpiration.                                                                                                                          (1/2) It is defined as the process of loss of water in vapour form from the aerial parts (leaves) of the plant.     (1) Transpiration is important because it helps ingenerating a pull for water and minerals upwards through xylem. It also helps to maintain plant temperature. The stomatal cells open or close to regulate exchange of gases and transpiration in plants.           The opening and closing of stomata is guidedby guard cells through the process of turgid and flaccid condition. This turgid and flaccid condition of guard cells is due to osmosis (endosmosis and exosmosis) i.e., when theguard cells take up water and become turgid, the stoma opens and when guard cells lose water and shrink, it closes.                                                                                                                                                                               (2)