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:
An energy pyramid is a model that shows the flow of energy from one trophic level to the next along a food chain. The pyramid base contains producers—organisms that make their own food from inorganic substances. All other organisms in the pyramid are consumers
Explanation:
Answer and Explanation:
Corals are a type of invertebrate within the <u>phylum Cnidaria</u>. They live in colonies of many identical individual polyps.A set of tentacles surround a central mouth opening. They also have a simple, radially-symmetrical body containing a single opening that serves as both the mouth and anus. The body is made up of two layers of cells, separated by a jelly-like layer with no internal organ. The two layers of cells make a single cell surrounding the body.
Answer:
Explained below:
Explanation:
Type of homeostatic mechanism in the human body which is most common is the maintenance of body fluids, dilute and solutions of water that carry liquefied chemicals found in internal part of the cell and the surroundings of them. the internal part of the cells, it is named as intracellular fluid, the external part of the cells, it is named as extracellular fluid. All the materials such as oxygen, nutrients, proteins, and ions, are needed for survival.
