AP Biology: Big Ideas The Study of Life

What is Biology? Science The study of life A set of concepts, theories, and principles that allow people to understand the natural world

AP Biology Curriculum & Framework What this means for you is that the test should be easier! We are faced with the challenge of balancing breadth of content coverage with depth of understanding AP Biology has shifted from a traditional “content coverage” model to one that focuses on enduring, conceptual understandings and the content that supports them Given the speed with which scientific discoveries and research continuously expand scientific knowledge, we are faced with the challenge of balancing breadth of content coverage with depth of understanding

Enduring Understandings To foster this type of learning, the breadth of content coverage is defined in a way that distinguishes content essential to support the enduring understandings from the many examples or applications that supports them

Emphasis on Science Practices A practice is a way to coordinate knowledge and skills in order to accomplish a goal or task Science practices enable you to establish lines of evidence and use them to develop and refine testable explanations and predictions of natural phenomena

Overview of the Concept Outline Big Ideas encompass core scientific principles theories and processes governing living organisms and biological systems For each Big Idea I will identify enduring understandings which incorporate the core concepts that you should retain from the learning experience The key concepts and related content that define the revised AP Biology course and exam are organized around a few underlying principles called Big Ideas which encompass core scientific principles theories and processes governing living organisms and biological systems

How we have to organize content Underlying Content: stuff you have to memorize Illustrative Examples: the context in which you have to understand the content You DON’T have to memorize this You do have to be able to understand these Exclusion Statements: stuff you definitely don’t have to know Concept & Content Connections: where 2 seemingly different topics intersect Learning Objectives: what you should know and be able to do with the knowledge

4 Big Ideas The Process of evolution drives the diversity & unity of life Biological systems utilize free energy and molecular building blocks to grow, reproduce, and maintain dynamic homeostasis Living systems store, receive, transmit, and respond to information essential to life processes Interactions within biological systems lead to complex properties

Characteristics of Living Things All living things: Have an orderly structure Can produce offspring Grow & develop Adjust to changes in the environment

Living Things Are Organized All living things show an orderly structure, or organization All living things are composed of one or more cells Each cell contains genetic material which provides all the information needed to control the organisms life proceses

Structure and Function are related at all levels Analyzing a biological structure gives us clues about what it does and how it works

Living Things Make More Living Things Living things reproduce their own kind Reproduction: production of offspring by an organism

Reproduction Requires Heritable Characteristics Life on Earth uses the nucleic acid DNA and codes for Heritable Information.

Is reproduction essential for the survival of an individual? NO It is essential for the continuation of the species, not the individual Species: a group of organisms that can interbreed and produce fertile offspring in nature

The donkey and the horse are both members of the genus Equus, but they are different species. They are similar enough genetically to produce offspring, why aren’t they members of the same species?

Living Things Change During Their Lives An organisms life begins as a single cell Over time, this single cell grows and takes on the characteristics of it’s species Growth results in an increase in the amount of living material and/ or the formation of new structures

Organisms increase in size and complexity Growth - increase in size. Development - increase in complexity.

Living things Adapt to Their Surroundings & Transform Energy Organisms live in a constant interface with their environment including Air Water Weather Plants Animals The ability of organisms to respond to stimuli is a necessary characteristic

Evolutionary Adaptations involve both responding to your environment and growth/ development over time Organisms change over time as they adapt to their environment.

Energy Utilization Organisms are “open” systems, they must continually take in energy. Organisms take in energy and transform it to do work.

Response: how the organism reacts to the stimulus Stimulus: anything in an organisms environment that causes an organism to react in some way Response: how the organism reacts to the stimulus For Example: Homeostasis Regulation of an organisms internal environment to maintain conditions suitable for it’s survival Huh??? Lets talk about this, can anyone give me an idea of what they think homeostasis is in normal language? Can anyone give me an example of a homeostatic process?

Homeostasis Homeostasis is a characteristic of life It is a process that occurs in all living things The way it works is through feedback mechanisms “homeo” = same “stasis” = state

Homeostasis Example Its hot outside so you sweat Your body detects the loss of water and makes you thirsty  you drink a glass of water homeostasis is restored! Everybody is happy 

Living Things Adapt & Evolve Adaptation: any inherited structure, behavior, or internal process that enables an organism to respond to environmental factors and live to produce offspring There are always some variations in the adaptations of individuals within a population of organisms

Success of an Organism is measured by: 1. Survival 2. Reproduction Note – organisms survive because of their adaptations, they do not adapt to survive.

Is this a “good” adaptation? Organisms must adapt, move, or die! Is this a “good” adaptation?

Individuals with more suitable adaptations are more likely to survive and reproduce As a result, individuals with these adaptations become more numerous in a population, gradually changing the species Evolution: the gradual changes of a species through adaptations over time

Science is a Process The Scientific Method Observation/ Stating a Problem Gather Information Form a Hypothesis Experiment /Test the hypothesis Data Collection/ Analysis Drawing Conclusions

Observations: Are the “keystone” to Science. If it can’t be “observed”, it can’t be studied by the Scientific Method. Can be made through your senses or through the use of tools.

Reasoning Induction Deduction Specific observations to reach general conclusion Deduction From general premise make specific prediction

Process of Science Observational Science Experimental Science Naturalists, human genome May lead to experiments Experimental Science Hypothetico-Deductive Science Hypothesis Deductive reasoning

Researching and Gathering Information Before testing a hypothesis it is useful to learn as much as possible about the background of the problem Often, other scientists have found information that is helpful in determining the types of tests to run

Hypothesis Hypothesis: an explanation for a question or problem that can be formally tested A Hypothesis is NOT a random guess Scientists make a hypothesis based on observation, extensive reading, and/ or previous investigations

Testing the Hypothesis The purpose of forming a hypothesis is to offer an explanation for something Once a hypothesis is made, it should be tested to see if the results disprove or support your hypothesis If the results disprove your hypothesis, does this mean you wasted your time? If your results support your hypothesis, does this mean your absolutely right?

Comment Nothing is ever proven in science Can be disproven Experiments either support or fail to support a particular hypothesis. Disproving a hypothesis is as important as supporting it These experiments are not a failure Conclusions and new hypothesis.

Experimenting Experiment: An investigation that tests a hypothesis by the process of collecting information under controlled conditions. Example: You’re baking a cake that calls for vegetable oil in the recipe, and you want to try it with butter, the control is the original cake with oil

2 Ways to Describe Things Quantitative: information that uses numbers or measurements 30 students in a class 7 meters long Qualitative: information that expresses qualities or behavior Blue sky Smooth surface

Quantitative Data May be used to make a graph or table Should be reported using the SI system International System of Measurement SI standards are understood & universally accepted by scientists throughout the world Each type of SI measurement has a base unit

SI Base Units Quantity Measured Unit Symbol Length Meter m Mass Gram g Time Second s Electric Current Ampere A Temperature Kelvin K Intensity of Light Candela cd Amount of Substance Mole mol

SI Prefixes The SI system is based on multiples of 10 Prefixes are used with the names of the units to indicate what multiple of 10 should be used with the units For Example: Kilo = 1000 So if you have 1 kilogram, you have 1000g

Common SI Prefixes Prefix Symbol Multiplying Factor Kilo- K 1,000 Deci- d 0.1 Centi- c 0.01 Milli- m 0.001 Micro- µ 0.000 001 Nano- n 0.000 000 001

Qualitative Information Qualitative data are given in written or verbal descriptions, and are not easily described using a numeric value When you make observations during an experiment, these usually fall under the banner of qualitative data Quantitative = quantity or number Qualitative = quality, what something is like

Science & Society Scientific research often provides society with important information that can be put to practical use Sometimes the methods used to make the discovery are controversial Sometimes the discovery itself can be taken and used for unsavory purposes

Ethics Refers to the moral principles and values held by humans Problem: not all humans have the same values and principles Knowledge gained through scientific research is, itself neither inherently good or inherently evil

Variables In a controlled experiment, only one variable is changed at a time. Dependant Variable: the result of what you changed Independent Variable: the thing you changed or are looking at

Dependant Variables Dependant Variable: the condition that results from changes to the independent variable What happens because you made a change In the previous example, the dependant variable might be that the cake burns because you used butter instead of oil The cake only burns if you use butter, so the burning (dependent variable) is dependant on if you use butter (independent variable)

Independent Variables Independent Variable: in an experiment, the only condition that is tested The factor that effects the outcome of the experiment In the previous cake example the independent variable would be oil or butter

Constants & Controls To be certain that you are really testing weather butter or oil make a better cake, you must keep other possible factors the same for each test or trial Constant: a factor that does not change when other variables do Control: a standard by which the test results can be compared

Scientific Theories are Broader in scope than hypothesis Not determined by single experiment, but have been supported by many experiments by many scientists A Scientific theory is an explanation of things or events based on knowledge gained from many observations and investigations Theories can be modified

Examples of Theories Atomic Theory Gravitational Theory Theory of Relativity Cell Theory Theory of Evolution by Natural Selection

Scientific Laws A Scientific Law is a statement about what happens in nature and seems to be true all the time Laws tell you what happens under certain conditions Laws do not explain why or how something happens A theory can be used to explain a law

Summary Themes can provide a common framework for learning Biology What are the characteristics of Life? What is Science and how does it work? Evolution’s role in the study of Biology