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.
Not many plants and animals are lucky enough be turned into fossils. When an animal or plant dies its remains usually rot away to nothing. Sometimes though, when the conditions are just right and its remains can be buried quickly, it may be fossilised. There are several different ways fossils are formed.Here we go through the five steps of fossilisation to make a typical 'mould and cast' fossil. An animal dies, its skeleton settles on the sea floor and is buried by sediment. An animal dies and its body sinks to the sea floor.ometimes though, when the conditions are just right and its remains can be buried quickly, it may be fossilised. There are several different ways fossils are formed. Here we go through the five steps of fossilisation to make a typical 'mould and cast' fossil.
Mold fossils are fossil impressions left after the animal or plant decomposes. They are negative images and often formed by the animal being left in acidic groundwater. Silt deposits form over the animal or plants impression after the shells or organic matter dissolves. An imprint is left. This void is called a mold.rue-form fossils are body parts of an animal or remains of a substance. They are often formed when the organism is caught in ice, tree sap or tar. Complete features are left behind.