Here are some plant terms & definitions that may help you understand what you are reading at various places.
Annual - It completes life cycle in a single year Biennial - It completes life cycle in two years; the first year typically as a rosette and the second year it bolts (flowers) Perennial - It lives more than two seasons. Evergreen - It keeps its leaves year round. Deciduous - It looses its leaves at the end of the growing season.
Root Types
Tap - It has one main root Fibrous - It has many equal roots, ie no dominant roots. Drosera Adela is a good example. Adventitious - This is a root that develops from a part of the plant other than another root, like the prop roots of maize or the tendrils of ivy. Root Hairs - These are the tiny outgrowths of the epidermis designed to absorb water and minerals. Epidermis -
Stem Terminology
Node - This is the region to which the leaf is attached. Internode - This is the region between nodes. Bud - These are found at the base of leaves and are immature shoot systems. Axillary bud - These are found at the base of leaves along the stem. These are what grow when you do a Nemesis cutting. Terminal Bud - This is the bud at the end of a stem. Bud Scales - Modified leaves creating a protective covering over the bud. Bud Scale Scar - This a the scar left on a stem where the terminal bud scales fell off. Leaf Scar - This is the scar left on the stem after a leaf has been detached. Lenticel - This is areas on the stem for gas exchange.
Leaf Parts
Blade - This is the main photosynthetic part. Petiole - This is simply the leaf stalk. Stipules - This is the appendage at the base of the petiole in some leaves, completely lacking in many plants.
Meristems - Growth in plants is restricted to certain regions called meristems. These can be found at the tips of roots and stems and are responsible for growth in length.
Here are some diagrams I have found from various places that show the different plant parts. None of the following images belong to me. Click on the names to see the diagrams.