Q12. Answer in short.
1. What are stomata?
2. Which gases are exchanged between green leaves and atmosphere
through stomata?
3. What are heterotrophs?
4. Why do algae and fungi live together in lichens?
5. What are parasitic plants?
6. How is peristalsis useful?
7. How are intestinal villi important?
8. What are ruminants?
9. Name the organs that make up the alimentary canal.
10. How long does food stay in the stomach?
1. Why do All living things need food?
2.What is the difference between ingestion and egestion?
3.When we take a bite of bread, it does not taste sweet initially. But
after sometimes, it starts to taste sweet. Why?
4.The gastric glands present in our stomach produce HCl which activates
the enzyme pepsin to digest proteins. Then, why is it our stomach does
not get digested/damaged by the action of the acid?
5.What happens to the food in the stomach?
6.What happens to the food in the small intestine?
Answers
Answer:
Ans 1. Stomata are the tiny openings present on the epidermis of leaves. We can see stomata under the light microscope. In some of the plants, stomata are present on stems and other parts of plants. Stomata play an important role in gaseous exchange and photosynthesis.
Ans2. The exchange of oxygen and carbon dioxide in the leaf
Ans 3. A heterotroph is an organism that eats other plants or animals for energy and nutrients. The term stems from the Greek words hetero for “other” and trophe for “nourishment.”
Ans 4. Pepsin Pearls
Pepsin is a stomach enzyme that serves to digest proteins found in ingested food. Gastric chief cells secrete pepsin as an inactive zymogen called pepsinogen. Parietal cells within the stomach lining secrete hydrochloric acid that lowers the pH of the stomach. A low pH (1.5 to 2) activates pepsin.
Ans 5. After food enters your stomach, the stomach muscles mix the food and liquid with digestive juices. The stomach slowly empties its contents, called chyme, into your small intestine.
Ans6. The small intestine absorbs most of the nutrients in your food, and your circulatory system passes them on to other parts of your body to store or use. Special cells help absorbed nutrients cross the intestinal lining into your bloodstream.