1-1 What is Science Section Assessment

What is the goal of science?

to investigate and understand the natural world, to explain events in the natural world, and to use those explanations to make useful predictions

In which two ways can a hypothesis be tested?

a testable experiment; gathering new data

What is asexual reproduction?

an identical offspring is produced from a single parent

Why is it advantageous for scientists to test only one variable at a time during an experiment?

to determine which variable is responsible for the observed results

How does an observation about an object differ from an inference about that object?

observation gathers qualitative sensory data about an object; inference gathers data about an object based on prior experience or present knowledge and research

What is quantitative data?

represented as numbers obtained by counting or measuring

Describe three possible ways in which a hypothesis may arise.

using prior knowledge, logical inference, and informed creative imagination

How did the design of Pasteur's flask help him successfully refute the hypothesis of spontaneous generation?

the long curved neck of the flask remained open to the air, but microorganisms from the air did not make their way through the neck into the flask until the curved neck was removed

What is a variable?

a factor in an experiment that can change

What is a scientific hypothesis?

a proposed explanation

What is qualitative data?

descriptions; data that can't usually be counted

What is homeostasis?

internal conditions must be fairly constant within organisms for survival

What equipment did Redi use in his experiment?

jars, type of meat, location, thermometer, calendar time, and gauze

What biological process includes chemical reactions that break down materials?

metabolism

What question was Spallanzani's experiment designed to answer?

microorganisms will not grow in boiled and sealed gravy but will grow in boiled gravy that is left open to the air

Why is it misleading to describe science as a collection of facts?

rather than unchanging knowledge, science is an ongoing process

What was the procedural flaw in John Needham's experiment?

the gravy was not heated to its boiling point

How do scientists today usually communicate their results and conclusions?

through computer email, skype, and webinars; presentations; and publication in a scientific journal

What variable was controlled in Spallanzani's experiment?

boiling temperature of the gravy

Why is skepticism considered a valuable quality in a science?

scientists must be open minded and consider new hypothesis if data demand it

What is sexual reproduction?

two cells from different parents unite to produce the first cell of the new organism

Name an example of homeostasis.

when you feel cold you begin to shiver, the muscles used when you shiver help warm you up; when you feel hot, sweating help to cool you down

Is a scientific hypothesis accepted if there is no way to demonstrate that the hypothesis is wrong?

a scientific hypothesis must be testable; scientists continually evaluate the strengths and weaknesses of hypotheses; they are open minded and modify hypotheses if data deem it

How does a hypothesis help scientists understand the natural world?

a tentative explanation for a set of observations

What is a theory?

a well-tested explanation that unifies a broad range of observations and enables scientists to make accurate predictions about new situations

Describe five characteristics of living things.

Living things are made up of cells, reproduce, grow and develop, respond to their environment, and are based on a universal genetic code

Why was the gauze important?

this was the only variable that was manipulated

What does it mean to describe a scientist as skeptical?

questions existing ideas and new hypotheses

What does science study?

the natural world

What is a control?

all other variables, except the factor you want to observe, should be unchanged

What topics might biologists study at the community level of organization?

all the populations that live in an area, their interactions; the food chains, how the population can adapt to a natural disaster

Why is Redi's experiment on spontaneous generation considered a controlled experiment?

all the variables were controlled except for one - whether or not there was gauze over each jar