Plant anatomy or phytotomy is the general term for the study of the internal structure of plants.
Flower anatomy
Calyx
Corolla
Androecium
Gynoecium
Leaf anatomy
Leaf anatomy
Stem anatomy
Stem structure
Fruit / Seed anatomy
Ovule
Seed structure
Pericarp
Accessory fruit
Wood anatomy
Bark
Cork
Phloem
Vascular cambium
Heartwood and sapwood
Branch collar
Root anatomy
Root structure