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.
1.1.3 Types of fossils. There are many ways in which a record of an organism can be preserved. Body fossils can occur in many ways, including: unaltered preservation, recrystallization, replacement, permineralization, carbonization, impressions, casts and internal molds..2.2 Other types of fossils. 1  1. Trace fossils. 2  Unlike body fossils, where a portion of the actual organism or its skeleton is preserved, trace fossils are the remains of an organism's activity or behavior. 3  Examples include tracks, trails, burrows, and borings. 4  Trace fossils will be covered in detail in a later lab. 5  2.
Three concepts are important in the study and use of fossils: (1) Fossils represent the remains of once-living organisms. (2) Most fossils are the remains of extinct organisms; that is, they belong to species that are no longer living anywhere on Earth. (3) The kinds of fossils found in rocks of different ages differ because life on Earth has changed through time. Stratigraphic ranges and origins of some major groups of animals and plants.