Which of the following are not secondary metabolites in plants ?

The correct option is Amino acids, glucose.

To understand why, we can classify plant metabolites into two main categories: primary metabolites and secondary metabolites.
1. Primary Metabolites: These are organic compounds that play a direct role in the normal growth, development, and reproduction of plants. They are essential physiological molecules found in all plants. Examples include carbohydrates (like glucose), proteins, amino acids, lipids, and nucleic acids.
2. Secondary Metabolites: These are organic compounds that are not directly involved in the essential growth, development, or reproduction of the plant. Instead, they serve ecological functions such as defense against herbivores and pests, attraction of pollinators, and protection against environmental stress. Examples include alkaloids, flavonoids, terpenoids, rubber, and gums.

Let us analyze the given options:
- Morphine, codeine: These are alkaloids, which are classic examples of secondary metabolites.
- Amino acids, glucose: Amino acids are the building blocks of proteins, and glucose is a primary source of cellular energy. Both are vital for basic cellular functions and survival, making them primary metabolites (and thus, not secondary metabolites).
- Vinblastin, curcumin: These are secondary metabolites (alkaloid and phenolic compounds respectively) often used for medicinal purposes.
- Rubber, gums: These are polymeric substances that function in wound healing and defense, classifying them as secondary metabolites.

Hence, amino acids and glucose are the substances that are not secondary metabolites in plants.