III. Answer the following questions in brief :
1. What happens when yeast is added to dough?
2. Why is a cyst formed in some micro-organisms?
3. What does brown algae owe its name to?
4. Which organism shows a symbiotic relationship with its partners
5. What do you mean by food poisoning ?
6. Which protozoan can photosynthesise, and why?
7. What are the various shapes of bacteria?
8. How does a paramaecium feed and move?
Answers
Answer:
the bubbles of carbon dioxide fill dough and cause dough to rise
Answer:
1ans : yeast makes dough rise
3ans: pigment fucoxanthin
4ans: (I) fungi and liches
(ii) Rhizobium and pants
5ans: Microorganisms that grows on our food sometimes produces toxic substances this makes the food poisonous causing serious illness and even death
6ans: monera,Euglena are the protozoans which can photosynthesis
7ans: there ate 4 main of bacteria
(l)COCCUS : spherical shaped
ex: streptococcus , pneumonia
(ll) BACILLUS: rod shaped
ex: bacillus anthracis and Escherichia coil
(lll)SPIRILLUM : spiral shaped
ex: leptospira, SPIRILLUM
(lv) VIBRIO : comma shaped
ex : vibrio cholera