Your Instructor
Dr. Brenda Latham
Ph.D. in Biology
1997
B.S. in
Biological Science 1991, Chemistry minor
A.A. in Liberal
Studies 1984
Chapter 1
An
Introduction to Life on Earth
Objectives for Today
Introduction
Define biology
Why study
biology?
Scientific Method
What is Life,
anyway?
Why is life so
diverse?
Biology is the scientific study of life
Why Study Biology?
Because
you have to?
Also:
Biology Helps You
Understand Your Body
Biology Helps You
Become an Informed Citizen
Biology Can Open
Career Opportunities
Biology Can
Enrich Your Appreciation of the World
How Do Biologists Study Life?
The Scientific
Method Is the Basis for Scientific Inquiry
Scientific Method
A biologist is a
scientist and accepts only answers that are supported by evidence, and then
only by a certain kind of evidence.
What kind?
Easily shared
with others
Repeatable
Well-Designed Experiments Incorporate
Controls
The experiments
of Francesco Redi
Well-Designed Experiments Incorporate
Controls
The experiments of Malte Andersson
How Do Biologists Study Life?
Experiments
Are Not Always Possible
A
feathered dinosaur
How Do Biologists Study Life?
Science requires
communication
so testing can continue
Scientific Theories
Have Been Thoroughly Tested
A scientific theory is
.. an established and experimentally verified fact or
collection of facts about the world. Unlike the everyday use of the word
theory, it is not an unproved idea, or just some theoretical speculation. The
latter meaning of a 'theory' in science is called a hypothesis.
..an extremely well-substantiated explanation of some aspects
of the natural world that incorporates facts, laws, predictions, and tested
hypotheses. (Eg, Einstein's Theory of Gravitation,
1916)
A scientific theory is
..a set of propositions which summarize, organize, and explain
a variety of known facts, eg Darwin's theory of evolution. Theories are
intended to logically summarize information and to give a framework for the
generation of new tests and ideas on the topic
In conclusion...
Hypotheses are
supported, not proven. New information or technologies can always overturn old
truths.
Thus, scientific
theories must be falsifiable- there must be some experiment or possible
discovery that could prove the theory untrue.
How do you define life?
What is the
essential difference between a bunny (or a tree) and a
rock?
What is the
essential difference between a live bunny and a bunny thats been run over?
Life can only be
defined by its characteristics
Life is defined by its characteristics
Living things are
both complex and organized
Living things
grow and reproduce
Living things
respond to stimuli
Living things
acquire and use materials and energy
Living things use
DNA to store information
What Is Life?
Living Things Are
Both Complex and Organized
What Is Life?
Living Things
Grow and Reproduce
What Is Life?
Living Things
Respond to Stimuli
What Is Life?
Living Things Use
DNA to Store Information
Characteristics of life
Complexity and
Organization
Reproduction and
growth
Respond to
Stimuli
Acquire and Use
Materials and Energy
Use DNA to Store
information
Evolution is the Backbone of Biology
Evolution
accounts for both lifes unity and Its diversity
All living things
are related
Same information
molecules (nucleotides)
Same basic
structure (cells)
Common ancestry
modified by natural selection
Natural selection eliminates inherited
traits that decrease the chance of survival in a certain environment by
differential survival and reproduction
Biodiversity
The spectrum of divergent life-forms
3 Domains
Bacteria
Archea
Eukarya
Bacteria and Archea
Unicellular
No nucleus
Differ in
important aspects of biochemistry, structure
The Four Eukaryotic Kingdoms
Animalia
Plantae
Fungi
Protista
We categorize eukaryotes into a hierarchy
Domain
Kingdom
Phylum or
division
Class
Order
Family
Genus
Species
Eukarya
Animalia
Chordata
Mammalia
Primates
Hominidae
Homo
Homo sapiens
Back to schedules:
MWF
TTH
Biology Home
Merced College Home