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An antler on a red deer stag. Velvet covers a growing antler, providing blood flow that supplies oxygen and nutrients. Each antler grows from an attachment point on the skull called a pedicle. While an antler is growing, it is covered with highly vascular skin called velvet, which supplies oxygen and nutrients to the growing bone. [6]
Velvet antler is the whole cartilaginous antler in a precalcified growth stage of the Cervidae family including the species of deer such as elk, moose, and caribou. Velvet antler is covered in a hairy, velvet-like "skin" known as velvet and its tines are rounded, because the antler has not calcified or finished developing.
However, the antenna does not hang free on the membrane, but pivots on a rigidly sprung projection from the rim of the torulus. That projection on which the antenna pivots is called the antennifer. The whole structure enables the insect to move the antenna as a whole by applying internal muscles connected to the scape.
Based on how much of the carbon-14 isotope remains in the object, scientists are able to determine an objective age. As bone, antler and horn are all derived from living organisms, determining the level of carbon-14 versus carbon-12 is considered quite effective and is the most widely used form of absolute dating. [27]
This dead bone structure is the mature antler. In most cases, the bone at the base is destroyed by osteoclasts and the antlers eventually fall off. [ 62 ] As a result of their fast growth rate antlers place a substantial nutritional demand on deer; they thus can constitute an honest signal of metabolic efficiency and food gathering capability.
Non-vascular plants , with their different evolutionary background, tend to have separate terminology. Although plant morphology (the external form) is integrated with plant anatomy (the internal form), the former became the basis of the taxonomic description of plants that exists today, due to the few tools required to observe. [2] [3]
Plant physiology – subdiscipline of botany concerned with the functioning, or physiology, of plants. [1] Cell biology – study of the cell as a complete unit, and the molecular and chemical interactions that occur within a living cell. Histology – study of the anatomy of cells and tissues of plants and animals using microscopy.
Plant development is the process by which structures originate and mature as a plant grows. It is a subject studies in plant anatomy and plant physiology as well as plant morphology. The process of development in plants is fundamentally different from that seen in vertebrate animals. When an animal embryo begins to develop, it will very early ...