Chapter 1Biology and You

Characteristics of Living OrganismsBiology is the study of life.

All living organisms share certain general properties that separate them from nonliving things.

Properties of LifeCellular organizationReproductionMetabolismHomeostasisHeredityResponsivenessGrowth and development

Branches of Biological ScienceTypes of Biological Science Clip

BotanyZoologyEcology

Themes of BiologyAs you study biology you will repeatedly encounter the

following seven themes.

1. Cellular Structure and Function2. Reproduction3. Metabolism4. Homeostasis5. Heredity6. Evolution7. Interdependence

Cellular Structure and function All organisms are made of cellsCells are the smallest unit of lifeOrganisms can have one cell or more than

one cell

Reproduction

All living things can reproduceMaintains the populations size Needed for survival of the species

Metabolism

Metabolism - Sum of all chemical reactions

Includes ways to obtain and use energy

Digestion

Homeostasis

Homeostasis – maintaining stable internal conditions regardless of external environment

Internal environment vs. external environment

Desert and tundra life

Heredity

Passing on traits / genes to the next generation

Parent offspring

Gene – basic unit of heredity

Evolution

Small changes to a population over large periods of time

Interdependence

Interactions between different species

Beneficial or harmful

Section 3: Scientific ProcessesObservation is the act of noting or perceiving

objects or events using the senses.

Scientific investigations begin with observations.

Observations cause scientists to ask questions about their observations.

Stages of Scientific InvestigationScientific 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.

Scientific MethodIncludes the following steps:

Collecting ObservationsAsking QuestionsForming a Hypotheses and making

Predictions Hypotheses – educated guess Prediction – expected outcome of a test

Confirming Predictions Experiment – planned procedure to test hypothesis

Drawing Conclusions

Pieces of an ExperimentControl Group – group that does not changeExperimental Group – group that changes in

1 wayIndependent Variable – factor that is changedDependent Variable – factor that is measured

Independent Variable

Dependent Variable

Scientific ExplanationsTheory – Set of

related hypothesis that have been tested many times by many scientists