Invertebrate zoology

What is invertebrate zoology?

Invertebrate zoology is the study of animals with no backbone, vertebral coloumn and spinal cord.

What is geologic time?

Geologic time is the frame work in which biologists attempt to account for the origin of the earth and the history of life on earth.

According to geologic times, how old is the earth and how much eras is the earth divided into?

The earth is approximately 5 billion years old and is divided into 5 eras.Archeozoic, Proterozoic, Paleozoic, Mesozoic and Cenozoic.

What is the most ancient and recent eras?

The most ancient is the Archeozoic era and the most recent is the Cenozoic era.

Precambrian Times

The two eras which refer to precambrian times are archeozoic and proterozoic. There was no life on earth during these eras.

The Cambrian Period

The first period of geologic times and began during the paleozoic era.

The Paleozoic Era

Paleozoic Era is known as the age of invertebrates. It is this era when life flourished and diversified according to fossil records, which are written in rocks/stones.

What is paleontology?

Paleontology is the study of fossils which reveals that most fossils were found in layers of sedimentary rocks.

Cenozoic Era

Is the only era which is defined by an epoch. Which are the smallet durations of geologic times.

Levels of Organization

The levels of orgainization are Organelles, Cells, Tissues, Organs and Systems.

How can we relate geolgic time to levels of organization?

Because levels of organizations describe the development or evolution of all invertebrate organisms. Some are only cells without tissues. Others with cells and tissues but no organs, still there are others with cells, tissues and organs and no systems. All higher invertebrates have fully developed organ systmes.