Era is used to mark the boundaries of geological time scale by using radio carbon dating technique.
Explanation:
Geological time starts with Precambrian time.
Geologically, time is divided between the Precambrian era and present time into era.
The three eras are Paleozoic era, Triassic period and Cenozoic era.
Era is further divided into periods.
Scientists use radio carbon dating to study fossils and rock formation. With this study they were able to divide them in exact geological scale.
Geologic scale is the record of events in earth's history and evolution.
A stamen is the name for male reproductive parts of the flower which consists of an <u>Anther and Filament</u>.
Answer: D)
Membrane proteins produce phospholids
Explanation:
Membrane proteins in the mitochondria do more than just generate cellular energy. The proteins in the membranes of the mitochondria are complex machines in the nanoworld that mediate the oxygen-coupled generation of energy in cells. Their role in this process is not yet understood in detail.
Membrane proteins perform a variety of functions vital to the survival of organisms: Membrane receptor proteins relay signals between the cell's internal and external environments. Transport proteins move molecules and ions across the membrane.
Vascular tissue composed of xylem<span> (red) and </span>phloem<span> tissue (green, between the</span>xylem<span> and </span>cortex<span>) surrounds the pith. Collenchyma cells are elongated cells with unevenly-thickened walls . They provide structural support, mainly to the stem and leaves.</span>
