2. Science
Science is an organized body of knowledge derived from observation and
study.
Science can be divided into two categories, depending on what is the subject
of study. These include:
Social Sciences such as psychology, sociology, and history
Natural Sciences that can be further divided into
• Physical Sciences -deal with the physical world and include chemistry,
physics, geology, astronomy, etc.
• Biological Sciences -deal with living organisms and include zoology,
botany, forestry, etc.
3. Life
Life is defined as the fact or act of living. The property of organisms
(ending at death) that makes it possible for them to take in food, grow,
and reproduce.
five major characteristics of life.
1. Living things -are organized (Highly organized and complex)
2. Living things -acquire materials and energy (Growth)
3. Living things -respond (Respond to environmental changes)
4. Living things -reproduce and develop
5. Living things -have adaptations
4. Life: Living things -are organized
Made up of at least one cell
Unicellular - made of one cell (bacteria, amoeba, paramecium)
Multicellular - made up of two or more cells (plants, fungi, animals)
Levels of Organization
1. Cellular Level: Atoms - molecules - organelles - cells
2. Organismal Level: Tissues - organs - organ systems
3. Population Level: Population - species - biological community
4. Ecosystem Level: Biological community + physical habitat (soil, water, atmosphere)
5. The Biosphere: The entire planet thought of as an ecosystem
5. Life: Living things -acquire materials and energy
Growth
Increase in cell size (unicellular) and/or
an increase in cell number (multicellular)
6. Life: Living things -respond
Responsiveness
Reaction(s) to various stimuli
Examples of stimuli: light, heat, pH, vibration, smell,
etc.– earthworms respond to all of these
7. Life: Living things -reproduce and develop
Reproduction
Asexual- cell division (mitosis)—one cell becomes two Ex: bacteria
Sexual- union of sex cells (sperm and egg) Ex: plants and animals
Homeostasis
Maintaining the same state
Homeo = same, steady
Stasis = state
Examples: Water balance inside and outside of cell, Human body
temperature
8. Life: Living things -have adaptations
Changing to meet the needs of the environment
Examples:
1. Bird migration- behavioral adaptation
2. Human body temperature- Physiological adaptation
3. Hibernation- Physiological adaptation
4. Hare ear length (desert vs. arctic hares)- structural adaptation
9. Biology: What is Biology
It is the scientific study of life.
Biology (Greek or Latin origin)
• Bios = life
• Logos = study of
It is a branch of science
• A way of understanding nature.
A human endeavor
• An attempt to understand, explain, integrate and describe
the world of living things.
10. Biology: Why Study Biology?
Two important reasons for studying Biology:
Biology is relevant to our everyday experience
• Medical advances
• Addressing needs of growing human population
• Challenges of decreasing rate of biodiversity
• Biotechnology advances
Biology can be controversial
Examples: Dealing with endangered species?
Use of human fetal tissue in biomedical research?
Safety of irradiated foods?
11. Biology is the most Interdisciplinary science
Because organisms are made of chemicals
And chemicals are governed by the laws of physics
And physics uses mathematics to describe natural phenomena
And mathematics is the most useful tool in the world
Biologists must master chemistry, physics, and mathematics to master
biology
Biology is the most interdisciplinary science
12. Biology: Major Themes in Biology
Evolution by Natural Selection
Inheritance
Cells
Biological Classification
Bioenergetics
Homeostasis
Ecosystems
14. Biology: Scientific Attitudes
Apply to science and everyday life
Careful Judgment
Desire to Learn
Cause and Effect
Concern for Human welfare
15. Biology Pioneers: 1. Aristotle
Greek (1st bio. teacher) “Father of Biology and Zoology
Supported spontaneous generation theory
Created a theory of the elements : 4 elements:
A. Earth
B. Air
C. Water
D. Fire
-1st person to start classifying organisms
16. Biology Pioneers: 2. Hippocrates
Greek
“Father of Medicine”
Hippocratic Oath for doctors (part of his life-long legacy)
17. Biology Pioneers: 3. Leeuwenhoek
Dutch
His hobby was lens grinding
** He did NOT invent the microscope, he perfected microscope
lenses
He was the first person to see:
Bacteria, Protozoans, Red blood cells, Sperm cells
**He did NOT support spontaneous generation
18. Biology Pioneers: 4. Lister
British
Hospital conditions were dirty & infectious
Used phenol as a disinfectant
“Father of Aseptic Surgery”
19. Biology Pioneers: 5. Fleming
British
Accidentally discovered first antibiotic (penicillin)
20. Biology Pioneers: 6. Salk
Developed 1st polio vaccine injection (1955)
Didn’t patent vaccine, didn’t want to profit from his
discovery
21. Biology Pioneers: 7. Sabin
Developed oral polio vaccine (1959)
Vaccines are weakened forms of disease that tricks body
into making antibodies
22. Biology: Scientific method
1. Technical Method (Cookbook Approach)
-Materials are given
-Directions are logical and lead to a known conclusion
Ex: Water boils at what temperature F?
Directions:
1. Water in beaker
2. Heat until boiling
3. Use thermometer to measure temp.
23. Biology: Scientific method
2. Scientific (Research) Method
-No materials given
-No directions
-Unknown conclusion
4 Basic Steps of Scientific Method
1. Observation
2. Hypothesis- educated guess that tries to explain observation
3. Test or experiment
4. Conclusion (match=finished; no match= start over again)
24. Biology: Scientific method
Begins with observations about our surroundings.
Next, ask questions about the phenomena we are observing.
Followed by generating a hypothesis.
Tentative explanation to the question.
Testing
Scientists perform tests to determine the accuracy of their hypothesis.
Explanation
It is a hypothesis that has passed the widest and most comprehensive
series of tests.
Still subject to review and consideration.
May be elevated to a theory = well demonstrated principle.
