The fossil record of Antarctica shows the presence of tropical plants, such as one particular species related to the present day breadfruit. Most plants cannot survive in prolonged temperatures of less than 6 degrees Celsius. Antarctica is freezing all year round and could only have supported tropical and sub tropical plants if it was once much closer to the equator.
The presence of fresh water species also suggest that the continent was closer to the equator. Antarctica is frozen solid with a thick ice sheet.....rivers would be frozen solid all year round or would be limited to water movement under glaciers that melt as a result of pressure and friction. This environment is not suitable to support large fresh water organisms.
The answer is C.
A virus is made up of or consists of a nucleic acid in varying quantity which may either be RNA or DNA.
The nucleic acid is surrounded by a protein shell called a capsid. The word capsid comes from the Latin word capsa which means box.The capsid and the nucleic acid within it are together referred to as nucleoprotein.The capsid is made up of small sub units called capsomeres.
In many viruses, the nucleoprotein makes up the whole virus. More complex viruses have one or more further enclosing structures also made mostly of protein. These structures are referred to as envelopes and each envelop is specific to a particular virus.
It is an example of a withdrawal reflex.
