A-Level Biology Question Analysis Topic: Biology - Plants
Exam Question:
Mention how have plants developed mechanical and chemical defence against herbivores to protect themselves with the help of one example of each.
Answer:
For A-Level Biology, you should know:
Both large and tiny herbivores actively chew plants for sustenance. Different defence mechanisms have been created by plants to deter or eliminate intruders.
Mechanical defences - Plants have an intact, impermeable barrier made of bark and a waxy cuticle that serves as their first line of defence. Both safeguard plants against herbivores. Hard shells, thorns, and spines are a few more defence mechanisms against herbivores. They deter animals by harming them physically or by triggering allergic reactions and rashes, e.g. thorns on roses.
Chemical defences - The plant must switch to an alternative set of defence mechanisms, such as toxins and enzymes, if the initial line of protection is compromised. Compounds known as secondary metabolites are not produced by photosynthesis directly and are not required for respiration or the growth and development of plants. An example of this is alkaloids that are poisonous to herbivores.
Work hard for your A-Level Biology examination!
End of analysis. Great!
