Post on 30-Mar-2018
transcript
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
The Study of Life
Table of Contents
Section 1 Introduction to Biology
Section 2 The Nature of Science
Section 3 Methods of Science
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Characteristics of Living Organisms
Biology is the study of life.
All living organisms share certain general properties that separate
them from nonliving things.
Properties of Life
» Cellular organization
» Reproduction
» Metabolism
» Homeostasis
» Heredity
» Responsiveness
» Growth and development
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Characteristics of Living Organisms, continued
• Cellular organization - every living thing is composed of one or more cells
• Reproduction - all living things are able to reproduce
• Metabolism - all obtain and use energy to run the processes of life
• Homeostasis - living organisms maintain a consistent internal environment
• Heredity - living things pass traits to offspring
• Responsiveness - all living things respond and adjust to the environment
• Growth and development - all living things grow and develop
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Biology
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Unifying Themes of Biology
As you study biology you will repeatedly encounter the following
seven themes.
1. Cellular Structure and Function
2. Reproduction
3. Metabolism
4. Homeostasis
5. Heredity
6. Evolution
7. Interdependence
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Unifying Themes of Biology, continued
1. Cellular Structure and Function • Cells are highly organized, tiny structures with thin
coverings called membranes. All living things are made of one or more cells. A cell is the smallest unit capable of all life functions.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Unifying Themes of Biology, continued
2. Reproduction • Reproduction is the process by which organisms
make more of their own kind from one generation to the next.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Unifying Themes of Biology, continued
3. Metabolism • Metabolism is the sum of all the chemical reactions
carried out in an organism. Almost all energy used by living organisms is originally captured from sunlight.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Unifying Themes of Biology, continued
4. Homeostasis • Homeostasis is the maintenance of a stable internal
conditions in spite of changes in the external environment. An organism unable to balance its internal conditions with its environmental conditions could become ill and die.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Unifying Themes of Biology, continued
5. Heredity • Heredity is the passing of traits from parent to
offspring. The basic unit of heredity is called a gene. Genes are coded in a molecule called deoxyribonucleic acid (DNA). Genes determine an organism’s traits. A change in the DNA of a gene is called a mutation. Most mutations are harmful, but some mutations can help an organism survive.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Unifying Themes of Biology, continued
6. Evolution • Evolution is defined as change in the inherited
characteristics of species over generations. A species is a group of genetically similar organisms that can produce fertile offspring. Natural selection is the process in which organisms with favorable traits are more likely to survive and reproduce.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Evolution
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Unifying Themes of Biology, continued
7. Interdependence • The organisms in a biological community live and
interact with other organisms. Ecology is the branch of biology that studies the interactions of organisms with one another and with the nonliving part of their environment. Organisms are dependent on each other and on their environment.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Unifying Themes of Biology
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Observation: The Basis of Scientific Research
Observation is the act of noting or perceiving objects or
events using the senses.
• All scientists have a certain way of investigating the
world.
• Scientific investigations begin with observations.
• Observations cause scientists to ask questions about
their observations.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Stages of Scientific Investigations
Scientific investigations tend to have common stages.
• These stages are called the Scientific Method.
• There is more than one way to conduct an
investigation.
• Scientific Methods or Scientific Processes are
more accurate terms for the stages of scientific
investigation.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Stages of Scientific Investigations, continued
Scientific Processes include the following stages.
• Collecting observations
• Asking questions
• Forming hypotheses and making predictions
• Confirming predictions (with experiments when
needed)
• Drawing conclusions
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Scientific Processes
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Stages of Scientific Investigations, continued
• Hypothesis—an explanation that might be true, a
statement that can be tested by additional
observations or experimentation
• Prediction—the expected outcome of a test,
assuming the hypothesis is correct.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Stages of Scientific Investigations, continued
• Experiment—a planned procedure to test a
hypothesis.
• Control group—a group in an experiment that
receives no experimental treatment. The control
group is necessary for comparing the results of the
experiment.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Stages of Scientific Investigations, continued
• Independent variable—the factor that is changed in
an experiment.
• Dependent variable—the variable that is measured
in an experiment, the outcome of the dependent
variable depends on what is done to the independent
variable.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Stages of Scientific Investigations, continued
Drawing Conclusions
Once data are collected
and analyzed, a conclusion
is made as to whether the
data support the
hypothesis.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Stages of Scientific Investigations, continued
Viewing Conclusions in Context
• There is often more than one possible reason for a
result.
• All of the factors that may affect an outcome must be
considered.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Scientific Explanations
Constructing a Theory
Theory a set of related hypotheses that have been
tested and confirmed many times by many scientists.
• A theory unites and explains a broad range of
observations.
• The word theory is used by the general public to
mean a guess, or lack of certainty.
• In science, a theory is a well-supported scientific
explanation that makes useful predictions.
Chapter 1
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Resources Chapter menu
Scientific Explanations, continued
Constructing a Theory
Scientists report their results.
• Scientific reports are reviewed by other scientists.
• Scientific reports allow other scientists to use the
information obtained in an experiment.
• Scientific reports also allow other scientists to repeat
and test experiments.
Chapter 1