Horizons
soil layers with specific characteristics
O-Layer
a soil horizon rich with organic matter and decomposing litter
A-Layer
zone of leacing, may be dark in color
B-Layer
zone of deposition
C-layer
parent rock
Name the 6 major macronutrients
Nitrogen (N), Potassium (K), Calcium (Ca), Magnesium (Mg), Phosphorus (P), and Sulfur (S)
Name the Micro Nutrients
Sodium (Na), Iron (Fe), Manganese (Mn), Chlorine (Cl), Copper (Cu), Zinc (Zn), Boron (B), and Molybdenum (Mo)
Adventitious Roots
roots that develop from the stem
Casparian Strip
a band of water resistant material in the radial walls of the endodermis
Endodermis
the innermost layer of cells of the cortex
Fibrous Roots
roots that are adventitious from the stem and replace a prominent tap root.
Lateral or Secondary Roots
roots that develop from the tap root.
Mycorrhizae
a symbiotic association between the root and a fungus.
Pericycle
the outer most layer of cells of the vascular cylinder.
Primary Meristem
the principle site of cel division in the root tip.
Prop Root
adventitious roots that grow from the stem and help hold the plant erect. I think these are like corn and other such crops.
Root Cap
a group of cells that protect the root tip as it grows through the soil. It is also the site of gravity detection.
Vascular Cylinder
the xylem and phloem of the root.
Bark
layers of stem tissue exterior to the vascular cambium
Cambial Zone
the cambium and its immediate derivatives
Cambium
a layer of dividing cells that forms the xylem toward the inside and the phloem toward the outside.
Cork
the outer covering of the plant that replaces the epidermis.
Growth Ring
the amount of xylem produced in one year
Lenticels
Lens shaped openings that develop through the cork and allow exchange of grasses through the cork.
Ray
a file of parenchyma cells running from the pith to the cortex.
Suberin
a waterproof material found in the walls of cork cells.
Wound Cork
cork produced where living tissue is exposed to air.
Apoplast
the cell walls and intercellular spaces of a plant
Cohesion
the tendency of like molecules to adhere or stick together
Hydrogen Bond
an attraction between a positively charged hydrogen atom in a polar molecule and a negatively charged oxygen or nitrogen atom in another polar molecule.
Plasmodesmata
thin, rotoplasic strands connecting cells.
Polar Compound
a chemical bond in which electrons are shared unequally among participating atoms, resulting in differences in charge in different areas of a molecule.
Pressure Flow Hypothesis
an explanation for the way organic compounds, including sugar, move throughout the plant.
Spheres of Hydration
water molecules forming shells around ions, keeping them from interacting.
Symplast
all the connected protoplasms of the cells of a plant.
Tension
in a column of water molecules, a result of the cohesion of water molecules.
Translocation
the movement of organic compounds within the plant.
Transpiration
the evaporation of water from the leaf.