Home
Class 12
BIOLOGY
Explain with the help of two examples ho...

Explain with the help of two examples how certain plants have evolved morphological and chemical defenses against primary consumers such as cows and gosts.

Text Solution

Verified by Experts

Plants have evolved an astonishing variety of morphological and chemical defenses against herbivores. For example, thorns found in cactus are the most common morphological means of defence, secondly, calotropis plant produces highly poisonous cardiac glycosides and thats why you never see any cattle or goats browsing on this plant.
Promotional Banner

Topper's Solved these Questions

  • XII BOARDS

    XII BOARDS PREVIOUS YEAR|Exercise SECTION-E|12 Videos

  • XII BOARDS

    XII BOARDS PREVIOUS YEAR|Exercise [OUTSIDE DELHI : SET-II] SECTION -A|2 Videos

  • XII BOARDS

    XII BOARDS PREVIOUS YEAR|Exercise OUTSIDE DELHI SET III|10 Videos

  • SAMPLE PAPER 2019

    XII BOARDS PREVIOUS YEAR|Exercise Section E Part B|3 Videos

Similar Questions

Explore conceptually related problems

Explain mutualism with the help of any two examples. How is it different from commensalism?

Explain with the help of one example how genetically modified plants can (a) Reduce usage of chemical pesticides. (b) Enhance nutritional value of food crops.

(a) What is an ion ? How is an ion formed ? Explain with the help of two examples of different ions. (b) The valencies (or charges) of some of the ions of are given below : Using this information, write down the formulae of the following compunds : (i) Sodium phosphate , (ii) Ammonium sulphate (iii) Calcium hydroxide , (iv) Lead bromide

With the help of two suitable examples, explain why certain experiences and traits earned by people during their lifetime are not passed on to their next generations. When can such traits be passed on?

(a) How are polygenic inheritance and multiple allelism different ? Explain with the help of an example each. (b) List the criteria a chemical molecule must fulfill to be able to act as a genetic material.

XII BOARDS PREVIOUS YEAR-XII BOARDS-COMPTT
  1. (a) What is an "allergic reaction"? (b) Name any two drugs used to q...

    Text Solution

    |

  2. Identify a, b, c,d,e and f in the following table :

    Text Solution

    |

  3. List any two types of IUDs that are available for human females and st...

    Text Solution

    |

  4. Mention the rule of (i) selectable marker, (ii) Ori and (iii) rop in E...

    Text Solution

    |

  5. Write the aim with which animal breeding programmes are carried. Descr...

    Text Solution

    |

  6. (a) Draw a diagram of sectional view of human ovary and label (i) Prim...

    Text Solution

    |

  7. (a) Draw a diagram of Pistil showing pollen tube growth in angiosperm...

    Text Solution

    |

  8. What was the challenge for production of insulin using rDNA techniques...

    Text Solution

    |

  9. Identify A, B, C, D, E and F in the table given below :

    Text Solution

    |

  10. Name the organism from which the 'cry' genes are isolated. Mention wit...

    Text Solution

    |

  11. Excessive and continous use of pesticides has resulted in evolution of...

    Text Solution

    |

  12. Explain with the help of two examples how certain plants have evolved ...

    Text Solution

    |

  13. What type of organs eye of an Octopus and that of a human called? Give...

    Text Solution

    |

  14. With the revolution in information technology, now it has become an in...

    Text Solution

    |

  15. (a) Explain the steps involved in in-vitro fertilisation popularly kno...

    Text Solution

    |

  16. (a) State one difference and one similarity between geitonogamy and ...

    Text Solution

    |

  17. (a) Hershey and Chase carried their experiment in three steps : infect...

    Text Solution

    |

  18. Taking an example of white-winged moths and dark-winged moths of Engla...

    Text Solution

    |

  19. (a) Write the percentage of land area that was covered by forests by t...

    Text Solution

    |

  20. (a) Comment on the pattern in which all communities undergo a change i...

    Text Solution

    |