Download App

Organisms and Populations — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYOrganisms and Populations3 Marks
Question
Explain with the help of two examples, how certain plants have evolved morphological and chemical defenses against primary consumers such as cows and goats.
✓

Answer

  1. Thorns and spines are the most common morphological means of defence.
Example: spines of Acacia and cacti.
  1. Many plants produce and store chemicals, which when consumed by the herbivores make them sick, inhibit digestion, disrupt reproduction or even kill them.
Example: Calotropis produces highly poisonous cardiac glycosides.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "3 Marks Question" from Organisms and Populations→Organisms and Populations — all question types→BIOLOGY STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

Distinguish between gross primary productivity and net primary productivity.
→
How does a mutagen induce mutation? Explain with example.
→
Bt cotton is resistant to pest, such as lepidopteron, dipterans and coleopterans. Is Bt cotton also resistant to other pests as well?
→
Explain how biomagnification of DDT occurs in an aquatic food chain.
→
  1. Why are transgenic animals so called?
  2. Explain the role of transgenic animals in (i) Vaccine safety and (ii) Biological products with the help of an example each.
→
State in what ways Stanley Miller stimulated the conditions of-
  1. Primitive atmosphere on earth.
  2. Energy source at the time of origin of life.
  3. Formation of organic molecules of life to prove the theory of chemical evolution.
→
What is ecological succession? Where and why would the rate of succession be faster, in a newly created pond or a forest destroyed by a forest fire?
→
  1. Draw schematic diagrams of segments of a vector and a foreign DNA with the sequence of nucleotides recognised by EcoRI.
  2. Draw the vector DNA segment and foreign DNA segment after the action of EcoRI and label the sticky ends produced.
→
Your school has been selected by the Department of Education to organise and host an interschool seminar on "Reproductive Health - Problems and Practices". However, many parents are reluctant to permit their wards to attend it. Their argument is that the topic is "too embarrassing."
Put forth four arguments with appropriate reasons and explanation to justify the topic to be very essential and timely.
→
Generally, it is observed that human males suffer from hemophilia more than human females, who rarely suffer from it. Explain giving reasons.
→