Which of the following is not an example of a defense used by plants against herbivores?

Increasing the amount of non-woody tissues in the plant, which makes it less nutritious for herbivores

The correct answer is  Option (3) -more production of non-woody tissues.

Non-woody tissues are not a defense against herbivores. In fact, they are often more nutritious for herbivores than woody tissues. Therefore, the production of non-woody tissues would not be an effective defense against herbivores.

The other options are all examples of defenses that plants use against herbivores. Chemicals that make the plant taste bad or poisonous can discourage herbivores from eating the plant. Physical structures, such as thorns, spines, or hairs, can make it difficult for herbivores to eat the plant. And hormone-like chemicals that interfere with insect metamorphosis can prevent insects from developing into adults.

Morphological defenses include physical structures that make it difficult for herbivores to eat the plant, such as thorns, spines, or hairs. Chemical defenses include compounds that make the plant taste bad or poisonous, or that interfere with the herbivore's digestion or reproduction.

Some of the most common morphological defenses include:

• Thorns: Thorns are sharp, pointed structures that can make it difficult for herbivores to eat the plant. They are found in many different plants, including cacti, acacias, and roses.
• Spines: Spines are similar to thorns, but they are usually smaller and more numerous. They are found in many different plants, including cacti.

Some of the most common chemical defenses include:

• Alkaloids: Alkaloids are a group of nitrogen-containing compounds that are found in many different plants. They are often bitter or poisonous, and they can deter herbivores from eating the plant. Some common alkaloids include nicotine, caffeine, and quinine.
• Cyanogenic glycosides: Cyanogenic glycosides are compounds that release cyanide when they are broken down. Cyanide is a poisonous gas that can kill herbivores. Cyanogenic glycosides are found in many different plants, including Calotropis.

These are just a few examples of the many morphological and chemical defenses that plants have evolved against herbivores. These defenses help to protect plants from being eaten and help to ensure their survival.