Chapter 2. Principles of Science and Systems

is a process through which we understand the natural world by making precise observations, and conduct methodical research to test hypotheses. It is also a cumulative body of knowledge. (Use only one word per blank.)

Science

Scientists will not accept a test or experimental result just once; they demand replication and

Blank 1: reproducibility, repeatability, or reproduction

Contrast the words accuracy and precision by matching each to its correct meaning.

Accuracy--How close you are to the real measurement
Precision--How close your measurements are to each other

______ reasoning logically follows a general principle and applies it to a specific instance, whereas ______ reasoning uses specific observations to create a general rule.

Deductive; inductive

Which of the following is not a scientific hypothesis?

God does not exist because people get sick.

Science is both the accumulated body of knowledge produced by many scientists and __.

a process for understanding the natural world

A ______ is an explanation supported by many tests and is accepted by a general consensus of scientists.

scientific theory

Reproducibility and replication are ______.

demanded by scientists; they won't accept just a single test result

The likelihood of an event occurring is estimated by ______.

probability

You have a group of 5 students who all measure the length of a salamander that is 17 cm long. The measurements are: 16.1 cm, 16. 2 cm, 16.1 cm, 16.2 cm, and 16.2 cm. These measurements are ______.

precise but not accurate

If a scientist collected rainfall data for every day of the week, summed all the rainfall values together, and divided that total by the total number of days sampled, the researcher would find the _____ level of rainfall for the week.

mean

Match the type of reasoning to its correct description.

Deductive reasoning--Reasoning that logically follows a general principle and applies it to a specific instance
Inductive reasoning--Reasoning that uses specific observations to create a general rule

Statistics are useful in environmental science, as we use them to ______.

provide a degree of confidence in research findings
calculate the probability that observed results could have occurred by chance

A(n) ___ is a possible explanation of scientific phenomena that is testable.

hypothesis

A study of events that have already happened is a(n) ___ experiment

natural

Which of the following statements is true regarding a scientific theory?

A scientific theory takes longer to develop than a hypothesis.

The likelihood of something occurring is measured in terms of probability, which is based on ______.

standard statistical measures
previous measurements

In descriptive statistics, the mean is basically ______.

an average for a particular variable

Manipulative experiments are those in which at least some of the conditions are ______.

controlled

______ help in determining the probability that observed results could have occurred by chance.

Statistics

One of the primary benefits of using a numeric model to represent an environmental system is that ______.

variables can be altered without actually destroying anything

What is a natural experiment?

Study of an event that has already occurred

A(n) ___ is a network of processes and interdependent components through which matter and energy flow.

Blank 1: system or ecosystem

A(n) ___ system receives inputs from its surroundings and produces outputs that leave the system. A(n) ___ system, which is extremely rare, exchanges no energy or matter with its surroundings. (Use only one word per blank.)

Blank 1: open
Blank 2: closed

______ describes the tendency for a system to remain stable, and a ______ is an event that changes a system. ______ describes the ability for a system to recover from a change, and ______ describes a large-scale change to a system due to multiple disruptions.

Homeostasis; disturbance; Resilience; a state shift

Choose all the examples of manipulative experiments below.

A nutritionist records how much body fat people lose when they eat a vegetarian diet for 3 months.
A behaviorist records reactions of toddlers when their favorite toy is taken away, both in the presence of a parent and in the absence of a parent.

Well-established scientific ideas may be abandoned for new explanations due to new technologies and data. These paradigm shifts often ______.

are not readily accepted by scientists and the general public

are used to represent environmental systems. Although some are physical, most are numeric, and they vary from the simple to the very complex. At the present time, these are often used to predict climate change. (Use just one word for your answer.)

Models

A system in science describes a ______.

network of interdependent components and processes, with materials and energy flowing from one component of the system to another

Match the appropriate "system" scientific terms to their correct definitions.

Open system--Receives inputs and produces outputs
Closed system-Exchanges no energy with its surroundings
Throughput--Energy that flows in, through, and out of a system

Scientific information is commonly misunderstood by the general public because:

the media, politicians, and private enterprise do not present the facts in an unbiased manner.

Match the system science terms to their correct definitions.
Instructions

Homeostasis--Tendency for a system to remain stable
Disturbance--An event that changes a system
Resilience--The ability for a system to recover from a change
State shift--A large-scale change to a system due to multiple disturbances

Major changes in scientific thought are ______ that occur when old explanations no longer are adequate for explaining new observations.

paradigm shifts

Politicians, private enterprise, and the media may not present scientific information accurately, such as information about climate change, because:

they may have an interest in how the information affects them.