seed coat
Kernel's outer layer
The seed coat is the protective outer layer of a seed, developed from the ovule's integuments after fertilization.
It shields the embryo and stored nutrients from physical damage, pathogens, and desiccation until conditions favor germination.
Seed coats vary widely—some are thin and papery, others hard enough to require scarification before the seed can sprout.
Outer seed integument
- integumentNatural outer covering
- hilumSeed's umbilical mark
- chalazaEgg's internal anchor cord
- rapheSeamlike junction in tissue
endosperm · embryo · cotyledon · pericarp · ovule · radicle · plumule · endocarp
Intentional shallow skin cuts
- stratificationDivision into distinct levels
- hydrationBodily fluid replenishment
- osmosisSolvent crossing semipermeable barrier
- permeabilityAbility to transmit fluids
dormancy · viability · sprouting · emergence · radicle · rupture · swelling · activation
Dry seed covering
- chaffProtective seed coverings
- branCereal grain husk
- threshingExtracting grain from stalks
- winnowingSeparating grain from chaff
milling · dehulling · polishing · grain · cultivar · breeding · cleaning · grading
Obstruction preventing passage
- impermeabilityResistance to passage
- desiccationComplete removal of moisture
- defenseProtection against harm
- dormancySuspended biological activity
waterproofing · insulation · hardness · tannins · phenolics · lignin · cuticle · waxes
testa
Outer seed integument
- integumentNatural outer covering
- hilumSeed's umbilical mark
- chalazaEgg's internal anchor cord
raphe · endosperm · embryo · cotyledon · pericarp · ovule · radicle · plumule · endocarp · aril
scarification
Intentional shallow skin cuts
- stratificationDivision into distinct levels
- hydrationBodily fluid replenishment
- osmosisSolvent crossing semipermeable barrier
permeability · dormancy · viability · sprouting · emergence · radicle · rupture · swelling · activation · chitting
husk
Dry seed covering
winnowing · milling · dehulling · polishing · grain · cultivar · breeding · cleaning · grading · storage
barrier
Obstruction preventing passage
- impermeabilityResistance to passage
- desiccationComplete removal of moisture
- defenseProtection against harm
dormancy · waterproofing · insulation · hardness · tannins · phenolics · lignin · cuticle · waxes · mucilage
- seed anatomyembryo, radicle, plumule, cotyledon, endosperm
- plant anatomyroot, stem, leaves, stems, leaf
- seedsflaxseeds, linseed, flaxseed, birdseed, corn kernel
- fiber sourcesbran, oats, wheat bran, whole grains, lentils
- plant biologyphotosynthesis, chloroplast, pollination, stamen, pistil
- hullshusk, chaff, bran, testa, pericarp