Search results
Results from the WOW.Com Content Network
Breaking dormancy, or finding the specific requirement of the seed, can be rather difficult. For example, a seed coat can be extremely thick. According to Evert and Eichhorn, very thick seed coats must undergo a process called scarification, in order to deteriorate the coating. [12] In other cases, seeds must experience stratification.
The seed coat forms from the two integuments or outer layers of cells of the ovule, which derive from tissue from the mother plant, the inner integument forms the tegmen and the outer forms the testa. (The seed coats of some monocotyledon plants, such as the grasses, are not distinct structures, but are fused with the fruit wall to form a ...
As the plant embryo grows at germination, it sends out a shoot called a radicle that becomes the primary root, and then penetrates down into the soil.After emergence of the radicle, the hypocotyl emerges and lifts the growing tip (usually including the seed coat) above the ground, bearing the embryonic leaves (called cotyledons), and the plumule that gives rise to the first true leaves.
Seed of Scouler's willow (Salix scouleriana) In botany , the radicle is the first part of a seedling (a growing plant embryo ) to emerge from the seed during the process of germination . [ 1 ] The radicle is the embryonic root of the plant, and grows downward in the soil (the shoot emerges from the plumule ).
The stages of germination of a pea plant: A. seed coat, B. radicle, C. primary root, D. secondary root, E. cotyledon, F. plumule, G. leaf, H. tap root. The part of the plant that first emerges from the seed is the embryonic root, termed the radicle or primary root. It allows the seedling to become anchored in the ground and start absorbing water.
A seedling is a young sporophyte developing out of a plant embryo from a seed. Seedling development starts with germination of the seed. A typical young seedling consists of three main parts: the radicle (embryonic root), the hypocotyl (embryonic shoot), and the cotyledons (seed leaves).
Leguminous seeds are examples of such sclerification. Larger sclereids form columns in the epidermis of pea, bean, and soybean seeds, and bone-shaped osteosclereids occur beneath the epidermis. In the seed coats of coconuts, sclereids possess numerous bordered pits. [2] These larger macrosclereids found in seed coats are of protodermal origin. [4]
The sclera forms the posterior five-sixths of the connective tissue coat of the human eyeball.It is continuous with the dura mater and the cornea, and maintains the shape of the eyeball, offering resistance to internal and external forces, and provides an attachment for the extraocular muscle insertions.