Search results
Results from the WOW.Com Content Network
The endodermis is the boundary between the cortex and the stele. In many seedless plants, such as ferns, the endodermis is a distinct layer of cells immediately outside the vascular cylinder (stele) in roots and shoots. In most seed plants, especially woody types, the endodermis is present in roots but not in stems.
The hand and spirit of God are absent; instead, there are men – never very strong, often ineffective, seldom secure, always troubled....Powell's narrative pictures the partial breakdown of an infantry company: the personal ossification of some men, the cracking of the mold in others, the failure (and even death) of still others.
A germ layer is a primary layer of cells that forms during embryonic development. [1] The three germ layers in vertebrates are particularly pronounced; however, all eumetazoans (animals that are sister taxa to the sponges) produce two or three primary germ layers.
The discovery of the Casparian strip dates back to the mid-19th century, and advances in the understanding of the endodermis of plant roots. [15] In 1865, the German botanist Robert Caspary first described the endodermis of the root of plants, found that its cell wall was thickened, and named it Schuchtzscheide.
Root tip, showing young root hairs. Root hairs or absorbent hairs, are outgrowths of epidermal cells, specialized cells at the tip of a plant root.They are lateral extensions of a single cell and are only rarely branched.
Between the xylem and phloem is a meristem called the vascular cambium. This tissue divides off cells that will become additional xylem and phloem. This growth increases the girth of the plant, rather than its length. As long as the vascular cambium continues to produce new cells, the plant will continue to grow more stout.
The outer surface of a bone is lined by a thin layer of connective tissue that is very similar in morphology and function to endosteum. It is called the periosteum , or the periosteal surface. During bone growth , the width of the bone increases as osteoblasts lay new bone tissue at the periosteum.
Some of the mesoderm derivatives include the muscle (smooth, cardiac, and skeletal), the muscles of the tongue (occipital somites), the pharyngeal arches muscle (muscles of mastication, muscles of facial expressions), connective tissue, the dermis and subcutaneous layer of the skin, bone and cartilage, dura mater, the endothelium of blood ...