External Structure and More
The section of a twig between nodes
internode
The older, inner wood of a stem that serves only to support the stem
heartwood
The process of a new plant growing from a root, stem, or leaf of an existing plant
vegetative reproduction
The tiny, tube-like projections that extend from the epidermal cells of a root to absorb water and minerals
root hairs
This part of a flower receives the pollen grains during pollination
stigma
The one-way diffusion of water through a semipermeable membrane
osmosis
The soft, thin-walled cells at the center of a young woody stem
pith
Examples include auxin, ethylene, and gibberellin
plant hormones
The part of a root tip in which cells grow longer
elongation
A high content of this pulls water out of the roots through osmosis and can kill plants
salt
Small openings in a stem's bark that allow air to enter the stem
lenticels
Wood is another name for this tissue
xylem
The tough outer covering of a herbaceous monocot stem
rind
The structure that covers and protects the tender root tip
root cap
The process in which substances mix through random molecular motion
diffusion
The growth of a plant toward or away from a stimulus such as light, water, touch, or gravity
tropism
The type of vascular tissue that carries water and minerals from a plant's roots and stem to the leaves
xylem
Plant seedlings that receive light from only one direction and bend toward the light
phototropism
Food is stored in this part of a root
cortex
The factors that drive this:
root pressure, capillarity, and transpiration pull
sap stream
The type of branching that has strong lateral buds and is usually rather close to the ground
spreading branching
Layering, grafting, and budding are types of this
vegetative propagation
Thick stems that grow horizontally under the ground and provide food storage and a means of vegetative reproduction
rhizomes
Special roots that grow from unusual regions of a plant
adventitious roots
Water enters a root through this process
osmosis