Pharmacognosy 2 Lecture 1: Fruits and Classification

Study Notes

Fruits are the mature ovaries and accessory parts of flowers that have developed.
Fruits typically contain seeds.
All fruits originate from flower ovaries and are found in flowering plants.
Fruits protect, nourish, and aid in seed dispersal.
The fruit wall, or pericarp, is divided into three layers: exocarp (outer layer), mesocarp (middle layer), and endocarp (inner layer).
Fertilization is the fusion of male and female gametes.
After fertilization, the ovary develops into a fruit containing seeds.
Fruits provide a protective structure and aid in seed distribution.
Flowers' parts involved in reproduction include the sepals, petals, stamens, and carpels.

Simple fruits develop from a single flower ovary.
Succulent fruits have fleshy pericarp (e.g., berries, drupes, pomes, hesperidia).
- Berries have fleshy pericarp and many seeds (e.g., tomatoes, grapes).
- Drupes have a hard endocarp, fleshy mesocarp, and a single seed (e.g., peaches, plums).
- Pomes have a fleshy, edible receptacle that surrounds the ovary (e.g., apples, pears).
- Hesperidia have a leathery rind, separate segments, and juicy hairs (e.g., citrus fruits).
Dry fruits have a leathery or woody pericarp (e.g., legumes, follicles, siliques, capsules).
- Legumes split along two sides (e.g., peas).
- Follicles split along a single seam (e.g., magnolia).
- Siliques and silicles are elongated with the septum between the two carpels (e.g., mustard family).
- Capsules have multiple carpels and open in various ways (e.g., cotton, opium poppy).

These originate from a flower cluster or inflorescence.
Types include aggregate fruits (e.g., raspberries) and multiple fruits (e.g., figs).

True fruits are formed from the flower's ovary.
False fruits involve other flower parts that contribute to their formation.
- Apples, for example, are developed from the receptacle and the ovary.