The right answer is vein (it contains blood and has valves).
The infra-cardiac veins of small and medium caliber possess this system of fight against gravity. The valves consist of a dense connective tissue, surmounted by endothelial cells, corresponding to a fold of the intima. They allow blood circulation in the sense organ / heart but prevent venous reflux.
Answer:
interaction of light and atoms
emission and absorption of light
A 16% probability of you rolling it
Both biome and <span>ecoregion </span>are ecological terms. Biome refers to a major regional group of plant and animal communities adapted to the natural environment. Biome can be of two types: terrestrial(land) andaquatic(water). <span>Ecoregion, </span>which is an abbreviated form of ''ecological region', refers to a smaller class. Each <span>biome </span>consists of severalecoregions, an ecoregion(also called bioregion) covering a realm of land/water having geographically distinctive communities, sharing the same envoronmental conditions and ecological dynamics.
Yes, an ecoregion does consist of different ecologically distinctive communities and species.
The correct answer for your question is C.
