As a result of immunodeficiency, most infected cats do not show symptoms and have normal life expectancy, however they are prone to developing other infections and certain types of cancer. A retrovirus, such as FIV, inserts a copy of its genetic material into the DNA of a host cell, where it can replicate. FIV is a lentivirus. a specific type of retrovirus that can take months, or even years to incubate, so the virus is slow moving, capable of lying dormant in the body before causing symptoms.
A fossil is the remains or traces of a once-living plant or animal that was preserved in rock or other material before the beginning of recorded history.The term also is used to describe the fossil fuels (oil, coal, petroleum, and natural gas) that have been formed from the remains of ancient plants and animals.nother type of fossil is the darkened carbon imprint of a buried plant or, more rare, animal. When an organism dies and is buried, pressure underneath Earth's surface compresses the organism between rock faces.
A fossil normally preserves only a portion of the deceased organism, usually that portion that was partially mineralized during life, such as the bones and teeth of vertebrates, or the chitinous or calcareous exoskeletons of invertebrates.ossils may also consist of the marks left behind by the organism while it was alive, such as animal tracks or feces (coprolites). These types of fossil are called trace fossils (or ichnofossils), as opposed to body fossils.