This document provides an overview and introduction to the fundamentals of biology. It discusses what biology is, the scope and levels of biological study from molecules to ecosystems. Key topics covered include the cell theory, evolution by natural selection, a brief history of life on Earth from the formation of early cells to the development of eukaryotes and multicellular organisms, and the diversity of life and relationships between organisms depicted in the tree of life. Scientific inquiry in biology is also introduced, including the scientific method and types of experiments used by biologists.

1. Fundamentals of Biology 1
BSC1010C
Dr. Rick Dexter

2. Introduction
• Syllabus
• Blackboard
• Study and Test Taking Techniques
• Lab Safety
• Safety Procedures
• Begin Chapter 1

3. Chapter 1- “Studying Life”
What is Biology?
- it is the
scientific study
of living things.

4. Scope of Biology
 Atoms/Molecules
(Biochemistry)
 Cells
 Tissue
 Organs
 Organism
 Population
• Species
 Communities
 Ecosystems
 Biosphere
 This course will focus
primarily on molecules and
cells

5. But what defines something
as a living thing?
• What are some general characteristics?
What about a virus?
In Summary…
An organized genetic unit capable of …
– Metabolism
– Homeostasis
– Reproduction
– Evolution

6. Discovery of the Microscope
The study of cells was made
possible by the invention of
microscopes.
Robert Hooke in the 1600s described
repeating units of plant material as
cells.

7. Robert Hooke – Plant Cork Cells
Nature Cell Biology 1, E13 - E15
(1999) – reproduced from
Micrographia, 1665

8. Early Cell
Theory
Louis Pasteur
(1859)
Disproves:
Spontaneous
Generation

9. Modern Cell Theory
• All cells come from preexisting cells.
• All cells are similar in chemical
composition.
• Most of the chemical reactions of life
occur within cells.
• Complete sets of genetic information
are replicated and passed on during
cell division.

10. Evolution
Change in the genetic makeup of
biological populations through time.
Charles Darwin (1859) proposed that all
living organisms are descended from a
common ancestor by the mechanism of
natural selection.

11. Charles Darwin – Theory of
Evolution
• Major unifying
principle of biology…
• Natural Selection
Traits that increase the
probability that the organism
will survive and reproduce will
become more common in the
population.

12. So how does Natural
Selection Work?
Within a Species, Variation in traits
due to Genetic Mutation gives rise
to individuals with higher
“Fitness”. Natural Selection is a
force that favors these individuals
within a population leading to an
Adaptation in the species.

13. Adaptations to the Environment

14. So how is all life on earth
related?
A common ancestor
All organisms are related
genetically
Tools used to study the
origins of life:
- Fossil Record
- Molecular Biology
(Compare Genomes)

15. Where did all Life’s Diversity come from?

16. 5 BYA - the Earth is Formed…
No Life on Earth, so how did it get there?
Two Theories:
1)ET Theory
2)Chemical Evolution (Currently
Accepted Theory)

17. 4 BYA –
Chemical
Evolution
leads to the
building
blocks of
life.
Miller-Urey
(1950’s)

18. 3.8 BYA – Vesicles Form
Biological molecules were then enclosed in
membranes, forming cells.
Increases the chance of interacting.
Resulted in the first single-celled organisms
called Prokaryotes
- Only found in the oceans
- Heterotrophs

19. 2.5 BYA - Photosynthesis
O2 accumulated in the
atmosphere
Aerobic metabolism
began
Ozone layer formed,
which allowed organisms
to live on land
Autotrophs

20. 1.5 BYA – Eukaryotes form
Karyon = kernel
eu = true
Organelles allow for
more specialized
cellular functions
Endosymbiosis
- Mitochondria
- Chloroplast

21. 1 BYA – Multicellular Structures
Cell
Specialization
Larger more
complex
organisms

22. Diversity - Tree of Life
Evolution results in speciation
Each species has a distinct scientific
name, a binomial:
• Genus name
• Species name
Example: Homo sapiens

23. Tree of Life
3 Domains
-Bacteria
-Archaea
-Eukarya
http://tolweb.org

24. How Do Biologists Investigate Life?
Biologists use many methods to
expand our understanding of life.
• Observation: improved by new
technologies
• Experimentation

25. Scientific Method
1. Observations
2. Questions
3. Hypotheses (tentative answer)
4. Predictions
5. Testing

26. So how does it work?

27. Inductive/Deductive logic
Inductive logic leads to tentative
answers or explanations called
hypotheses.
Deductive logic is used to make
predictions.

28. Types of Experiments
Controlled Experiments: manipulate the
variable that is predicted to cause
differences between groups.
- Control Group
- Independent Variable
- Dependent Variable
Comparative Experiments:
- Field Work

29. Class Activity