Chapter 1 The Science of Life

Biology The study of life…how do you know that something is alive? What are the signs?

The seven characteristics of life Cell organization Response to stimuli Homeostasis Metabolism Growth and development Reproduction Change through time

Cell organization Organelles make up the cells, cells make up the tissues, tissues make up the organs, organs make up the organ systems.

Response to stimuli Response to physical or chemical change…can be categorized as homeostasis as well, thereby eliminating it as its own group. Why?

Homeostasis The body’s ability to maintain stable internal conditions.

Metabolism All the chemical reactions that take in and transform energy and materials from the environment.

Growth and development The division and enlargement of cells. Can also be categorized under the heading of metabolism. Why?

Reproduction Produce new organisms like themselves. The other 6 characteristics are all individual organism characteristics, this one is whole species specific…to make it individual organism specific (so it fits in with the others more appropriately), it can be restated as: came from the reproduction of organisms like itself.

Change through time Basically the idea of evolution. Allows for species survival.

Science as a process The scientific method. Observation Hypothesis-testable prediction Prediction-what will happen if hypothesis is true Experiment Conclude Analyze- quantitative or qualitative. Also make statements about sources of error

Quantitative v. qualitative Quantitative can be explained with measurable numbers. Qualitative is not necessarily measurable by numbers. You may make an observation like “it is bigger” without using a true measuring tool.

Two important principles Events in the natural world have natural causes. Uniformity: the fundamental laws of nature operate the same way at all places at all times.

The Experiment A controlled experiment is is one with: Only one variable A control group Experimental group Independent and dependant variables.

Independent v. dependant variable Independent: The factor manipulated by the experimenter. It is the one difference between the control group and experimental group. Dependant: Varies in response to the independent variable.

Graphs-for analyzing data

Other ways to analyze data Tables Graphs Pie Line Scatter Bar Charts