Biology Chapter 1: The Study of Life

Introduction to Biology

• Growth results in the addition of mass to an organism and, in many organisms, the formation of new cells and new structures.
• A species is a group of organisms that can breed with one another and produce fertile offspring.
• A stimulus is anything that is part of the internal or external environments and causes some sort of reaction by the organism, and the reaction to a stimulus is a response.
• Examples of response to stimuli include the Venus flytrap.

Characteristics of Life

• Living things get their energy from food, and most plants and some unicellular organisms use light energy from the Sun to make their own food and fuel their activities.
• Organisms that cannot make their own food get energy by consuming other organisms.
• Regulation of an organism's internal conditions to maintain life is called homeostasis, and processes to restore the normal state begin if anything happens within or to an organism that affects its normal state.
• An adaptation is any inherited characteristic that results from changes to a species over time.

Biology

• Biology is the science of life, studying the origins and history of life and once-living things, the structures of living things, how living things interact with one another, and how living things function.
• Biologists study the diversity of life, research diseases, develop technologies, improve agriculture, and preserve the environment.

The Eight Characteristics of Life

• The eight characteristics of life are:
  • Made of one or more cells
  • Displays growth
  • Grows and develops
  • Reproduces
  • Responds to stimuli
  • Requires energy
  • Maintains homeostasis
  • Adaptations evolve over time

Cellular Organization

• Living things are made of one or more cells, which are the basic unit of structure and function in all living things.
• Cells are organized into groups that work together called tissues, which are organized into organs, and organ systems work together to support an organism.

The Nature of Science

• Science is a body of knowledge based on the study of nature, and scientific inquiry is both a creative process and a process rooted in unbiased observations and experimentation.
• A scientific theory is an explanation of a natural phenomenon supported by many observations and experiments over time.
• Scientific fields are guided by research that results in a constant reevaluation of what is known, leading to new knowledge and evaluation.
• Scientists welcome debate about one another's ideas, and sciences advance by accommodating new information as it is discovered.
• Observations or data that are not consistent with current scientific understanding are of interest to scientists, leading to further investigations.