General Biology: Chapter 1 Study Guide – Foundations of Life and Scientific Inquiry

Properties and Levels of Life

Defining Life and Its Organization

Biology is the study of living organisms and their interactions with the environment. Understanding the properties and levels of life is fundamental to the study of biology.

• Properties of Life: Living things share characteristics such as organization, metabolism, homeostasis, growth, reproduction, response to stimuli, and adaptation through evolution.

• Levels of Life: Life is organized hierarchically, from molecules to cells, tissues, organs, organ systems, organisms, populations, communities, ecosystems, and the biosphere.

• Basic Unit of Life: The cell is the fundamental unit of life. All living things are composed of one or more cells.

Information and Energy in Living Things

Molecules and Energy Use

Living organisms require information and energy to maintain life processes.

• Information Molecule: DNA (deoxyribonucleic acid) is the molecule that stores genetic information in living things.

• Energy Use: Organisms obtain and use energy to grow, reproduce, and maintain homeostasis. Energy is often acquired through processes such as photosynthesis (in plants) or cellular respiration (in animals).

Unity and Diversity of Life

Similarities and Differences Among Living Things

Biologists study both the unity and diversity of life to understand how organisms are related and how they differ.

• Unity: All living things share common features, such as cellular structure and genetic code.

• Diversity: Life is diverse due to evolutionary processes that lead to adaptation and speciation.

• Classification Systems: Organisms are classified into domains and kingdoms based on shared characteristics.

Classification and Domains

Organizing Life

Classification systems help organize the diversity of life.

• Three Domains: Life is classified into three domains: Bacteria, Archaea, and Eukarya.

• Taxonomy: The science of naming and classifying organisms.

Evolution and Natural Selection

Explaining Unity and Diversity

Evolution is the process by which populations change over time, leading to the diversity of life.

• Evolution: Explains both the unity (shared ancestry) and diversity (adaptation to different environments) of life.

• Charles Darwin: Proposed the theory of evolution by natural selection.

• Natural Selection: The process by which organisms better adapted to their environment tend to survive and reproduce.

Science and the Scientific Method

Nature and Process of Science

Science is a systematic way of understanding the natural world through observation and experimentation.

• What is Science? Science is based on evidence, observation, and reasoning.

• Outline of Scientific Method:

  1. Observation

  2. Question

  3. Hypothesis

  4. Prediction

  5. Experiment

  6. Analysis

  7. Conclusion

• Types of Science: Observational science involves gathering data through observation, while experimental science involves testing hypotheses through controlled experiments.

Key Vocabulary

Important Terms in Biology

• Biology: The study of living organisms.

• Producers: Organisms that make their own food (e.g., plants).

• Consumers: Organisms that eat other organisms.

• DNA: The molecule that carries genetic information.

• Eukaryote: Organisms with cells that contain a nucleus.

• Prokaryote: Organisms with cells that lack a nucleus.

• Taxonomy: The classification of organisms.

• Evolution: Change in populations over time.

• Natural Selection: Mechanism of evolution.

• Data: Information collected during scientific investigation.

• Qualitative: Descriptive data.

• Quantitative: Numerical data.

• Hypothesis: A testable statement about the natural world.

• Controlled Experiment: An experiment in which only one variable is changed.

• Theory: A well-supported explanation of natural phenomena.

• Inductive Reasoning: Making generalizations from specific observations.

• Deductive Reasoning: Making predictions based on general principles.

Clarification: Hypothesis, Prediction, and Experiment

Understanding Scientific Statements

In science, hypotheses and predictions are essential for designing experiments and interpreting results.

• Hypothesis: A statement that expresses what a scientist thinks is the answer to a proposed question. It is often written as an "If...then..." statement.

• Prediction: A hypothesis states the answer as if we believe it is true. For example, "My flashlight does not work because the batteries are dead." A prediction is made from the hypothesis, such as "If I replace the batteries, then my flashlight will work."

• Experiment: Tests the prediction to determine if the hypothesis is correct.

Table: Types of Data in Scientific Investigation

Type of Data	Description	Example
Qualitative	Descriptive, non-numerical	Color of leaves, shape of cells
Quantitative	Numerical, measurable	Height of plant (cm), number of cells

Table: Domains of Life

Domain	Cell Type	Example Organisms
Bacteria	Prokaryotic	Escherichia coli
Archaea	Prokaryotic	Halobacterium
Eukarya	Eukaryotic	Plants, animals, fungi, protists

Example: Scientific Method in Action

• Observation: The flashlight does not work.

• Question: Why does the flashlight not work?

• Hypothesis: The batteries are dead.

• Prediction: If I replace the batteries, then the flashlight will work.

• Experiment: Replace the batteries and test the flashlight.

• Conclusion: If the flashlight works, the hypothesis is supported; if not, the hypothesis is rejected.

Additional info: Expanded definitions and examples were added for clarity and completeness.