AP BIOLOGY

Detailed explanation-1: -Fossils are the remains or impressions of organisms, preserved in petrified molds or casts. They are particularly useful to biologists who can use them to discover extinct animal species, and and study the way that those animals evolved and lived.

Detailed explanation-2: -Impression fossils are a type of trace fossil. Impression fossils form when a leaf, shell, skin, or foot. leaves an imprint in soft earth. When the imprint hardens, it forms a fossil in the shape of the original.

Detailed explanation-3: -Mold: Fossils formed when the sediment surrounding a buried organism hardens. When the organism decays, its impression is left in the rock and can be seen if the rock is broken open.

Detailed explanation-4: -An imprint fossil, also known as an impression fossil or fossilized impression, is a fossil that doesn’t contain organic material. They are a form of trace fossil – a fossil that leaves evidence of an organism’s movements or activity. Examples of trace fossils include footprints, eggshells, nests and more.

Detailed explanation-5: -Sometimes, open pores in the rock let water and air reach the organism or part, causing it to decay or dissolve. What is left behind is a cavity in the rock where the organism or part was. This empty space is called a mold. A mold shows the original shape and surface of the organism or part.