Chapter 1 Test

Goals of Science

To provide natural and testable explanations for events that happen in nature.

First Step in Scientific Investigation

Observing and asking questions.

Hypothesis

A tentative explanation that can be tested by further observation or experimentation; it must be a testable statement.

Inference

A logical interpretation based on what a scientist already knows.

Controlled Experiment

A way to test a hypothesis in which only one variable is changed while all others are kept unchanged.

Independent Variable

The variable that is deliberately changed.

Dependent Variable

The variable that is observed and changes in response to the independent variable.

Experimental Group

The group in which all variables are controlled except for the one independent variable.

Control Group

The group in which all variables are controlled with no changes to the independent variable.

Controlled Variables

All of the other variables that should be kept unchanged or controlled.

Quantitative Data

Numbers obtained by counting.

Qualitative Data

Descriptive information that involves characteristics that can't be measured.

Instances Where Experiments Aren't Possible

Observing animal behavior in the wild; Ethical concerns in testing hypotheses, such as cancer research.

Theory

A tested, highly-reliable scientific explanation of events in the natural world that unifies many observations and incorporates well-supported hypotheses.

Peer Review

Scientists publish papers for peer review to allow replication of results and ensure accuracy, testability, and truthfulness.

Bias

A personal point of view for or against something; it can lead to misinterpretation of data and recommendations not in the public interest.

Engineers vs. Scientists

Engineers design and build machines and structures; both follow similar steps in inquiry and design.

Science and Engineering Practices

1) Developing and Using Models; 2) Using Mathematical and Computational Thinking; 3) Constructing Explanations and Designing Solutions; 4) Engaging in Argument from Evidence.

Biology

The study of life.

Characteristics of Life

1) Made of cells; 2) Reproduce; 3) Universal genetic code; 4) Grow and develop; 5) Need materials and energy; 6) Respond to environment; 7) Maintain internal balance; 8) Evolve.

Unicellular vs. Multicelluar

Unicellular organisms are made of a single cell; multicellular organisms are made of many cells.

Asexual vs. Sexual Reproduction

Asexual reproduction involves one parent; sexual reproduction involves two parents.

Growth vs. Development

Growth is an increase in size; development is the process of cell division leading to a mature organism.

Differentiation

The process in which cells become specialized in structure and function.

Metabolism

The combination of chemical reactions that build up or break down materials in an organism.

Internal vs. External Stimulus

Internal stimulus comes from within (e.g., hunger); external stimulus comes from outside (e.g., water for seeds).

Homeostasis

The process by which organisms maintain a relatively stable environment.

Crosscutting Concepts in Biology

1) Cause and Effect; 2) System and System Models; 3) Stability and Change; 4) Patterns; 5) Scale, Proportion and Quantity; 6) Energy and Matter; 7) Structure and Function.

Fields of Biology

1) Global Ecology; 2) Biotechnology; 3) Building the Tree of Life; 4) Ecology and Evolution of Infectious Diseases; 5) Genomics and Molecular Biology.

Definition of length, volume, mass, and temperature

Length - distance between two points; Volume - amount of space an object takes up; Mass - amount of matter in a substance; Temperature - degree of hotness or coldness.

Base Metric Units

Length - meter; Volume - liter; Mass - gram; Temperature - °Celsius.

Metric Prefixes

kilo- (k), hecto- (h), deca- (da), deci- (d), centi- (c), milli- (m), micro- (µ), nano- (n).

Common Celsius Temperatures

0°C (freezing point of water); 25°C (room temperature); 37°C (body temperature); 100°C (boiling point of water).

Laboratory Safety Rules

Know lab safety rules; follow teacher's instructions; wash hands after every lab activity.