Bio 101

Introduction

Biology - Bio· (life) & ·logy (study of)

The Scientific Method

“Rules” of scientific investigation

1. Observation - define the problem you wish to explain

Hypothesis - one or more falsifiable explanations for the observation
Experimentation - controlled attempts to test one or more hypotheses
Conclusion - was the hypothesis supported or not; accept or reject hypothesis

Scientific theory - A hypothesis tested several times.

1) Cell theory –

A) All organisms are composed of one or more cells

B) All cells have arisen from pre-existing cells.

2) Gene theory –

A) DNA is the physical carrier of inheritance

B) The hereditary info in the DNA is translated (via RNA) to build proteins

3) Theory of Evolution –

A) Adaptation – all organisms adapt to their environment

B) Variation – all organisms are variable in their traits

C) Over reproduction – all organisms tend to reproduce beyond their environment’s capacity to support them

D) Natural selection – since organisms are not equally adapted, some will survive and reproduce better than others

Adaptation

Growth / Development

Organization

Reproduction

Response to stimuli

Homeostasis – maintenance of a constant internal environment

Metabolism – acquisition & release of energy

Interactions (w/ each other & the environment)

I Principles of Cellular Life

Chemical Foundations for Cells

Element – a pure substance that cannot be decomposed by chemical change

Atom – the smallest unit of matter containing the properties of a particular element

Sub-atomic Particles

Atomic # – the number of protons in the nucleus

Atomic mass – the number of protons & neutrons

A neutral atom contains the same number of protons, neutrons, and electrons.

Isotope – A variant form of an atom; specifically, having the same number of protons but
a varying number of neutrons.