1 Introduction to Biology Copyright Cmassengale

2 Biology – The Study of Life Life arose more than 3.5 billion years ago First organisms (living things) were single celled Copyright Cmassengale

3 Characteristics of Life Copyright Cmassengale

4 Cells cells All living things are composed of cells Copyright Cmassengale

5 Organization (organelles) Specific cell structures (organelles) carry out particular functions Copyright Cmassengale

6 multicellular organisms, In multicellular organisms, cells and groups of cells (tissues) are organized by their function Cells Cells  tissues Tissues Tissues  organs Organs  Organs  systems systems Systems  Systems  ORGANISM ORGANISM Copyright Cmassengale

7 Energy Use metabolism Use energy in a process called metabolism Sum of all chemical processes Sum of all chemical processes Copyright Cmassengale

8 Homeostasis stable internal conditions Maintain stable internal conditions Temperature, pH, etc. Temperature, pH, etc. Copyright Cmassengale

9 Growth cell division and cell enlargement Growth occurs as the result of cell division and cell enlargement Cell division preexisting cell Cell division is the formation of two cells from a preexisting cell New cells enlarge as they mature Copyright Cmassengale

10 process by which an adult organism arise development The process by which an adult organism arise is called development cell differentiation Repeated cell divisions and cell differentiation Development Copyright Cmassengale

11 Reproduction ability to reproduce All species have the ability to reproduce Not essential to survival of individual Not essential to survival of individual but is essential for continuation of a species Copyright Cmassengale

12 Responsiveness Respond to stimuli Respond to stimuli in the external environment light, heat, sound and chemical and mechanical contact Detect and respond to changes in light, heat, sound and chemical and mechanical contact Copyright Cmassengale

13 Evolve evolution Ability to adapt to their environment through the process of evolution Favorable characteristics Favorable characteristics are selected for and passed on to offspring adaptations Called adaptations Driven by natural selection or “survival of the fittest” Driven by natural selection or “survival of the fittest” Copyright Cmassengale

14 Scientific Method Copyright Cmassengale

15 Observation – STEP 1 five senses Employing your five senses to perceive objects or events Copyright Cmassengale

16 Asking a Question – STEP 2 Based on observations; one or more questions are generated Copyright Cmassengale

17 The Hypothesis --- Is a statement made in advance that states the results that will be obtained from testing the hypothesis Is a statement made in advance that states the results that will be obtained from testing the hypothesis “if-then” statement Often written in the form of an “if-then” statement Copyright Cmassengale

18 Experimenting – STEP 3 Testing a hypothesis controlled conditions Testing a hypothesis or prediction by gathering data under controlled conditions Copyright Cmassengale

19 Organizing Data – STEP 4 Involves placing observations and measurement (data) in order Graphs, charts, tables, or maps Graphs, charts, tables, or maps Copyright Cmassengale

20 Analyzing Data – STEP 4 cont) Collected and organized data must be analyzed determining whether data are reliable or whether they support or do not support a hypothesis Process of determining whether data are reliable or whether they support or do not support a hypothesis or prediction Copyright Cmassengale

21 Conclusion – STEP 5 Conclusions are made on the basis of facts, not observations Copyright Cmassengale

22 Theories theory A theory may be formed after many related hypotheses have been tested and supported with experimental evidence broad statement of what is thought to be true A broad statement of what is thought to be true Copyright Cmassengale

Laws Statement of fact A Statement of fact that concisely explains an action or group of actions e.g. Law of Gravity Accepted to be true Accepted to be true Universal Universal 23 Copyright Cmassengale

MEASUREMENTS 24 Copyright Cmassengale

25 Measurements SI units or metric We will be using SI units or metric system when possible --- the WHOLE world uses it except us (USA) Copyright Cmassengale