Unifying Themes in Biology: Cell, Evolution, and Earth's History

Cell

Basic unit of life

Biological hierarchy

Atom molecule cell organelle cell tissue organ organ system organism population community ecosystem biosphere

Homeostasis

The regulation of an organism's internal environment

Metabolism

Chemical processes that maintain life.

Anabolism

Building up

Catabolism

Breaking down

Adaptation

Inherited traits that help organisms survive.

Generation-to-generation change in inherited genes in a population.

Evolution

Interaction between species: mutualism, commensalism, parasitism.

Symbiosis

Growth

Increase in mass

Change in abilities

Development

Asexual reproduction

One parent, identical offspring.

Two parents, genetically unique offspring.

Sexual reproduction

Anything that causes a change in an organism.

Stimulus

Reaction to a stimulus.

Response

Energy flow in ecosystems

Sunlight Producers Consumers Heat

Earth age

4.5 billion years

Life appearance on Earth

3.5 billion years ago

Anaerobic

First organisms

Cyanobacteria

First oxygen-producing organisms

Stromatolites

Layered mounds formed by cyanobacteria, early fossil evidence.

Paleontology

The study of fossils

Microfossils

Microscopic remains of ancient organisms.

Archaea, Bacteria, Eukarya

Three Domains of Life

proposed the Three Domains of Life

Carl Woese

Example of Archaea

Pyrolobus fumarii (heat-loving), Picrophilus (acid-loving).

Examples of Eukarya

Protists Fungi Plants Animals

Three theories on the origin of life

Creation Theory, Abiogenesis, Biogenesis