Name important defence mechanisms in plants against herbivory.
Solution and Explanation
Several plants have evolved various mechanisms both morphological and chemical to protect themselves against herbivory.
(1) Morphological defence mechanisms:
(a) Cactus leaves (Opuntia) are modified into sharp spines (thorns) to deter herbivores from feeding on them.
(b) Sharp thorns along with leaves are present in Acacia to deter herbivores.
(c) In some plants the margins of their leaves are spiny or have sharp edges that prevent herbivores from feeding on them.
(2) Chemical defence mechanisms:
(a) All parts of Calotropis weeds contain toxic cardiac glycosides which can prove to be fatal if ingested by herbivores.
(b) Chemical substances such as nicotine, caffeine, quinine, and opium are produced in plants as a part of self-defense.
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Concepts Used:
Population Interactions
Population interaction is generally between two different species populations.“Population interaction is the interaction between different populations. It refers to the effects that the organisms in a community have on one another.”
An ecosystem is a geographic area wherein plants, animals, and many other organisms, alongwith weather and landscape, work together to form a bubble of life.
Types of Population Interactions:
Interactions can be beneficial or neutral or detrimental. Accordingly, there are six types of population interaction.
The different ways populations interact with each other can be summarized under the following headings.
- Competition
- Predation
- Herbivory
- Mutualism
- Commensalism
- Parasitism
- Competition