1. Biology
Exploring Life

2. All forms of life share common properties
Life is defined by what living things do. 7 major processes/properties associated with living things
Have order (all living things are either single cells or made of many cells)- atoms, molecules, organelles, cells, tissues, organs, organ systems, organisms
Reproduce: make more of their own (cell division/sexual reproduction)
Grow and develop: increase in size, go through a series of changes (development) controlled by DNA

3. Process energy: use energy to carry out all life functions and to maintain homeostasis (internal balance)
Respond to the environment: stimulus/response (migration, movement toward light, etc.)
Regulation: have processes that regulate a constant internal environment (homeostasis) (shivering,

4. Hierarchy of Organization
At each level of organization new properties arise that were not present at the preceding level. (Emergent Properties)
Living organization begins at the cellular level. All living things are made of cells. Cells are made of atoms, molecules, and organelles-but these are not considered living.
DNA is an important molecule, but it is not a living thing
Organelles are tiny “organs” that perform a specific function for a cell, but alone they are not considered living

5. A group of similar cells that perform a specific function are tissues-tissues are considered living
A group of tissues form an organ (heart)
A group of organs form an organ system (circulatory system)
A group of organ systems form an organism (an individual living thing)

6. A group of organisms of the same species form a population
A group of populations form a community (plants and animals, fungi, bacteria)
A group of communities form and ecosystem
Groups of ecosystems form the biosphere (all of the ecosystems on earth that support life.)

7. Cells are the structural and functional units of life
Cells are the level of organization at which the properties of life emerge
All organisms are composed of cells. They occur singly or as the subunits of multicellular organisms.
Two main characteristics of cells
1. All cells are enclosed in a membrane that regulates what enters and leaves the cell
2. All cells use DNA as genetic information

8. 2 types of cells:
1. Prokaryotic: DNA is not enclosed in a membrane bound nucleus. No membrane bound organelles.
Smaller in size
Have existed on Earth for longer (evolved around the first 1.5 billion years of life on Earth
2. Eukaryotic: DNA contained within a membrane bound nucleus. Contains membrane bound organelles.
Larger in size
Evolved about 2.1 billion years ago

9. The properties of life emerge from the ordered arrangement and interaction of the structure of cells.
A system is the combination of the parts forming a more complex organization.
Because of the complexity of biological systems, biologists use an approach called systems biology which uses models to study the dynamic behavior within a system. Systems biology is based on the study of the individual parts of the system to explain the whole system.

10. Cells also help explain the correlation between structure and function
Cells also help explain the correlation between structure and function. A cells structure gives us clues as to it’s function (nerve cells)
All activity from movement to metabolism takes place at the cellular level.

11. Organisms Interact with their Environment
This interaction includes all living and non-living parts.
There are two major processes that are involved in this interaction
1. Recycling of chemical nutrients
producersconsumersconsumersdecomposers producers
Nurtients are recycled through the ecosystem

12. 2. The flow of energy
SunlightProducerschemical heatConsumerheatDecomposterheat
There must be a constant source of sunlight and heat is given off in each step in the flow of energy through the system. This means that each step has less available energy than the previous step.

13. The Unity of Life is Base on DNA and a Common Genetic Code
DNA is the chemical substance of genes. Genes are the units of inheritance and all cells have DNA
The molecular structure of DNA controls the transmittance of information from parents to offspring and controls the activities of the cell.
The diversity of life arises from the differences in the DNA sequence of nucleotides

14. DNA stand for Deoxyribonucleic Acid
DNA is composed of long chains of nucleotides
Nucleotides
A ribose sugar
A phosphate group
A nitrogen base

15. The Diversity of Life is Arranged into Three Domains
Life is not only organized within the biosphere from molecules to the biosphere, life is organized according to the diversity of living things.
Living things are grouped according to similarities. This grouping process (taxonomy) names and classifies species into a hierarchy of broader and broader groups: genus, family, order, class, and phylum to kingdom

16. Historically, biologists grouped all living things into 5 kingdoms
Using evolutionary relationships we now group all living things into one of three domains
Domain Bacteria (Prokaryotes, very diverse group)
Domain Archaea (Prokaryotes, live in very harsh environments-salty lakes, boiling hot springs)
Domain Eukarya (Eukaryotes, range from single cell protists to multicellular organisms)

17. Evolution explains the Unity and Diversity of Life
Fossils document the history of the changing Earth
Life has existed on Earth for billions of years
The Earth has been inhabited by an evolving cast of life forms
Evolution accounts for life’s:
Kinship(Similarities) and
Diversity Differences

18. Charles Darwin
Published On the Origin of Species by Means of Natural Selection in 1859
Provided evidence to support the idea of evolution and that species living today are descendants of ancestral species (descent with modification)
Natural Selection is the mechanism for evolution

19. Darwin made two observations:
1. Individuals in a population vary in their traits, many of which are passed from parent to offspring
2. A population can produce more offspring than the environment can support

20. From these observations, Darwin inferred:
1. Individuals with heritable traits best suited to the environment are more likely to survive and reproduce than less well-suited individuals
2. This unequal reproductive success over many generations will increase the proportion of individuals in the population with the advantageous traits
3. This will result in an evolutionary adaptation. The accumulation of favorable traits in a population over time.

21. The Process of Science Science: derived from the Latin verb “to know”
Scientists use inquiry: search for information and explanation
1. Discovery Science
2. Hypothesis-based Science

22. Discovery Science
Describes nature through observation and analysis of data
Data = recorded observations (quantitative/qualitative)
Inductive reasoning: generalizations derived from specific observations

23. Hypothesis-Based Science
Uses deductive reasoning: propose an explanation for a set of observations. Logic flows from general to specific.
Hypothesis: predictions that can be tested by observing or experimenting.
AP Biology will use: “If…., then ….. because” when writing our hypotheses.
A hypothesis must be testable and falsifiable

24. Experimental Design Hypothesis
Use control (the group in the experiment you will compare your results to) and experimental (the group that contains the factor you will be testing or observing) Controlled Experiment
Design:
Independent variable (IV) A variable that is changed intentionally to observe its affect on the dependent variable
Dependent variable (DV) What you measure in the experiment, what is affected during the experiment
Control
Constants
# of trials

25. Example: You are interested in how stress affects heart rate in humans
Example: You are interested in how stress affects heart rate in humans. Your independent variable would be the stress and the dependent variable would be the heart rate. You manipulate stress levels in your subjects and measure how those stress levels change heart rate.

26. Hypothesis Explanation to a specific question
Tested by experimentation or continued observation
Can be disproven (falsified) but cannot be proven true

27. Theory Summarizes a group of hypotheses supported by repeated testing
Broader in scope
New hypotheses can be generated from it
Supported by massive body of evidence

28. Law Statement of Fact Explains things but doesn’t describe them
Generally accepted to be true and universal
Basis for scientific method

29. Science is a social activity with most scientists working in teams
Scientists share information
Science seeks natural causes for natural phenomena
Limited to the study of structures and processes that wen can directly observe and measure
Hypotheses about supernatural forces or explanations are outside the bounds of science because they generate untestable hypotheses

30. Biology and Everyday Life
Biology, technology, and society are connected.
Issues facing society are related to biology and most involve expanding technology
The goals of science and technology differ
The goal of science is to understand natural phenomena
The goal of technology is to apply scientific knowledge for a specific use

31. Technology advances stem from scientific research
Scientific research benefits from new technology

32. Evolution is a core theme in biology
Evolution is useful in medicine, agriculture, forensics, and conservation
Human caused environmental changes are powerful selective forces that affect the evolution of many species
Antibiotic resistant bacteria
Pesticide resistant pests
Endangered species and extiction