1. The Study of Biology
Chapter 1

2. Life’s Organization
Defining life is challenging because of the complex properties that emerge from the interaction of simple properties
Emergent Property: characteristic of a system that does not appear in any of the system’s component parts
Same materials, different properties, each increasing level is more complex than the one before, with new emergent properties at each level

3. Life’s Unity Living things share a set of key characteristics.
1. Display Organization
[least complex] atom  molecule  cell  tissue  organ  organ system  multicellular organism  population  community  ecosystem  biosphere [most complex]
2. All living things are made of one or more cells.
Unicellular: made up of 1 cell
Multicellular: made up of many cells

5. Life’s Unity 3. Requires Energy & Nutrients
Nutrient: substance that an organism needs for growth and survival but cannot make for itself
Producers: organism that makes its own food using energy and nonbiological raw materials
Photosynthesis: producers use light energy to make sugars from carbon dioxide and water

6. Life’s Unity
Consumers: organism that gets energy and nutrients by feeding on tissues, wastes, or remains of other organisms
Energy is not cycled – It flows through the world of life in one direction: from the environment through organisms, and back to the environment

7. Life’s Unity 4. Maintain Homeostasis
Homeostasis: process by which organism keeps its internal conditions within tolerable ranges by sensing and responding to change
If anything happens within or to an organism that affects homeostasis, processes to restore it begin.
hot  sweat  cold  shiver

8. Life’s Unity 5. Respond to Environment 6. Reproduces
Stimulus: Anything that is part of the internal or external environments and causes some sort of reaction by the organism
Response: reaction to a stimulus
6. Reproduces
Reproduction: processes by which individuals produce offspring
Inheritance: transmission of DNA to offspring
All organisms inherit their DNA from one or two parents
DNA is the basis of similarities in form and function among organisms
Small variations in DNA give rise to differences among individuals and among types of organisms

9. Life’s Unity 7. Grows & Develops
Development: multistep process by which the first cell of a new multicellular organism gives rise to an adult
Growth: increase in the number, size, and volume of cells
8. Adaptations Evolve over Time
Adaptation: traits in a species that develop as a result of changes in the environment
Makes the organism well suited for their environment and passed on to future generations

10. Remember!
H omeostasis O rganization G rowth & development R esponds to stimuli A dapts C ells E nergy R eproduces

11. Life’s Organization
Taxonomy: the science of naming and classifying species
Genus: a group of species that share a unique set of traits
Species: unique type of organism
Together, these designate the species name – Homo sapien
Always italicized, genus is always capitalized

12. Science of Nature
Science: body of knowledge based on the study of nature.
Critical Thinking: deliberate process of judging the quality of information before accepting it

13. Biology Biology: the study of life
We also study the origin of life, structures of living things, how living things interact
Biologist: one who studies the diversity of life
Research diseases, develop technology, improve agriculture, preserve the environment

14. Scientific Method 1. Ask a question 2. Form a Hypothesis
Scientific inquiry begins with observation.
2. Form a Hypothesis
Hypothesis: testable explanation of a situation
Inductive Reasoning: drawing a conclusion based on observation
Prediction: statement, based on a hypothesis, about a condition that should exist if the hypothesis is correct
Deductive Reasoning: using a general idea to make a conclusion about a specific case

15. Scientific Method 3. Evaluate the Hypothesis
Model: analogous system used for testing hypotheses
Variable: characteristic or event that differs among individuals or over time
Independent Variable: manipulated by the experimenter, does not change
Dependent Variable: results from or depends on changes to the independent variable.
Control Group: group used for comparison.
Experimental Group: group exposed to the factor being tested.

16. Scientific Method 3. Evaluate the Hypothesis
Data: information gained from observations.
Quantitative Data: represents a measureable QUANTITY (time, temperature, length, mass, area, volume, density)
Qualitative Data: QUALITITIES or descriptions of what our senses detect (fuzzy, nice)

17. Scientific Method 5. Report 4. Draw Conclusions
Do your results support the hypothesis?
5. Report
Peer Review: process by which experimental procedures and the results are evaluated by other scientists in the same field or conducting similar research.

18. Scientific Method
Real World Application In 1996, the FDA approved Olestra, a fat replacement manufactured from sugar and vegetable oil, as a food additive. Potato chips were the first product to have Olestra. Soon after, people began complaining of intestinal problems after eating the chips, and blamed Olestra.

19. Scientific Method
Hypothesis: Olestra causes intestinal cramps
Prediction: IF Olestra causes cramps, THEN people who eat Olestra should be more likely to get cramps than people who do not eat it.
Experiment:
Control Group: Eats regular chips
Experimental Group: Eats Olestra chips
Dependent Variable: cramps?
Independent Variable: type of chips
Results: 17.6% of control group got cramps, 15.8% of experimental group got cramps
Conclusion: Percentages are about equal, people who eat either chip are likely to get cramps, the data does not support the hypothesis

20. The Nature of Science
Scientific Law: A statement about a phenomena which is unchanging under given conditions.
The Law of Conservation of Energy
Scientific Theory: A scientifically acceptable explanation of a phenomena based on scientific observations and data.
The Theory of Evolution
Don’t be fooled! Not everything with scientific vocabulary is actual science. If claims, arguments, or methods presented do no follow scientific principles, it is pseudoscience – FAKE!