1. Chapter 1: The Nature of Life
Section 1.1: What is Science?
Section 1.2: Science in Context
Section 1.3: Studying Life

2. 1.1 What science is and is not…
Science is an organized way of gathering and analyzing evidence about the natural world.
Science is different from other human endeavors because it only deals with the natural world, scientists collect and organize data looking for patterns and connections, and scientists propose explanations based on evidence.
From a scientific perspective, all objects in the universe are governed by universal natural laws whether the objects are large or small.

3. Goals of Science
One goal of science is to provide natural explanations for events in the natural world.
These explanations help us with predictions about natural events.

4. Science, Change, and Uncertainty
Almost every scientific discovery raises more questions than it answers.
Science rarely “proves” anything in absolute terms.
Uncertainty is part of the scientific process.
Why do you think there is uncertainty in science?

5. Scientific methodology: The heart of science
Scientists use a general style of investigation called Scientific Methodology.
Scientific methodology involves observing and asking questions, making inferences and forming hypotheses, conducting controlled experiments, collecting and analyzing data, and drawing conclusions.

6. Observing and asking questions
Scientific investigations begin with observation, the act of noticing and describing events or processes in a careful, orderly way.
What can you observe from this image?

7. Inferring and forming a hypothesis
An inference is a logical interpretation based on what scientists already know.
Inferences usually lead to a hypothesis.
A hypothesis is a scientific explanation for a set of observations that can be tested in ways that support or reject it.
What are some examples of a hypothesis?

8. Designing controlled experiments
Testing a scientific hypothesis often involves designing an experiment that keeps track of various factors that can change, or variables.
Whenever possible, a hypothesis should be tested by an experiment in which only one variable is changed.
All other variables should be kept unchanged or controlled. This type of experiment is called a controlled experiment.

9. Controlling variables
What is a variable?
The variable that is deliberately changed is the independent variable (manipulated)
The variable that is observed and that changes in response to the independent variable is called the dependent variable (responding).

10. Control and experimental groups
An experiment is normally divided into control and experimental groups.
A control group is exposed to the same conditions as the experimental group except for one independent variable.

11. Collecting and analyzing data
Scientists make detailed records of experimental observations, gathering information called data.
Two main types of data:
Quantitative data are numbers obtained by counting or measuring.
Qualitative data are descriptive and involve characteristics that cannot usually be counted.

12. Research tools
Research tools involve metersticks, calculators, microscopes, computers, graphs, journals, ect…

13. Drawing Conclusions
Scientists use experimental data as evidence to support, refute, or revise the hypothesis being tested, and to draw a valid conclusion.
Hypothesis are often not fully supported or refuted by one set of experiments.
In that case, the original hypothesis is reevaluated and revised; new predictions are made, and new experiments are designed.

14. When experiments are not possible
It is not always possible to test a hypothesis with an experiment.
Observations can replace controlled experiments.
Ethics sometime prevents experiments from being performed, ex: Medicine.

15. 1.2 Science in context
Scientific methodology is closely linked to exploration and discovery.
Good scientists share scientific attitudes, or habits of mind, that lead them to exploration and discovery.
Curiosity, skepticism, open-mindedness, and creativity help scientists generate new ideas.
What are some examples of curiosity, open- mindedness, and skepticism?

16. Practical problems
Sometimes, ideas for scientific investigations arise from practical problems.
Example: will removing salt marshes from the environment for housing projects affect the ecosystem a great deal?

17. The role of technology
Technology, science, and society are closely linked.
Discoveries in one field of science may lead to new technologies.
Those technologies in turn, enable scientists in other fields to ask new questions or to gather data in new ways.

18. Communicating results: reviewing and sharing ideas
Scientists focus on one subject intensely for months, even years before they decide to communicate their experiments and observations to the scientific community.
Peer review is when scientific work is reviewed by anonymous, independent experts.
Once research has been published it enters the dynamic market place of scientific ideas.

19. Scientific theories What is a theory?
A scientific theory describes a well-tested explanation for a range of phenomena.
It enables scientists to make accurate predictions about new situations.
Scientific theories are different from laws and theories DO NOT become laws.
What are some differences between theories and laws?

20. What’s the difference between theories and laws?
Theories are more dynamic and complex
They encompass a greater number of ideas and hypotheses and are constantly fine-tuned through the process of science.
Laws are concise, specific descriptions of how some aspect of the natural world is expected to behave in a certain situation.
*A useful theory that has been thoroughly tested and supported by many lines of evidence may become a dominant view among scientists but no theory is considered absolute truth.*

21. Science and society
Scientific research does not only include science itself, but also on the society in which we live.
Using science involves understanding its context in society and its limitations.
What would be some of our limitations when it comes to research?

22. Science, ethics, and morality
When scientists explain “why” something happens, their explanation involves only natural phenomena.
Avoiding bias; a bias is a particular preference or point of view that is personal, rather than scientific.
Science will keep changing as long as humans keep wondering.
Understanding biology will help you realize that we humans can predict the consequences of our actions and take an active role in directing our future and that of our plabet.

23. 1.3 Studying life What are some characteristics of living things?
Biology is the study of life.
No single characteristic is enough to describe a living thing.
We can list characteristics that most living things have in common.
Living things are made up of basic units called cells, are based on a universal genetic code, obtain and use materials and energy, grow and develop, reproduce, respond to their environment, and change over time.

24. Characteristics of living things
Living things are based on a universal genetic code.
All organisms store the complex information they need to live, grow, and reproduce in a genetic code written in a molecule called DNA.
This information is passed on from parent to offspring.

25. Characteristics of living things
Here’s a famous example of DNA…

26. Characteristics of Living things
Living things grow and develop.

27. Characteristics of living things
Living things respond to their environment.
A stimulus is a signal to which an organism responds.

28. Characteristics of living things
Living things are made up of cells.
Organisms are composed of one or more cells.

29. Characteristics of living things
Living things reproduce, meaning that they produce new, similar organisms.
There are two types of reproduction:
Sexual reproduction: When cells from two parents unite to form the first cell of a new organism.
Asexual reproduction: When a single organism produces offspring identical to itself.

30. Characteristics of living things

31. Characteristics of living things
Living things maintain a stable internal environment.
All organisms need to keep their internal environment relatively stable, even when external conditions change dramatically; this is known as homeostasis.

32. Characteristics of living things
Living things obtain and use material and energy.

33. Characteristics of living things
Taken as a group, living things evolve.
What does it mean to evolve?
Evolutionary change links all forms of life to a common origin more than 3.5 billion years ago.

34. Big ideas in Biology
The study of biology revolves around several interlocking big ideas:
Cellular basis of life
Information and heredity
Matter and energy
Growth, development, and reproduction
Homeostasis
Evolution
Structure and Function
Unity and diversity of life
Interdependence in nature
Science as a way of knowing

35. Big ideas in biology
All forms of life are connected into a biosphere which means “living planet”.
What’s the name of our biosphere?

36. Fields of Biology
Biology includes many overlapping fields that use different tools to study life from the level of molecules to the entire planet.
Botany
Ecology
Microbiology
Zoology
Biotechnology
Marine biology
Forensics
Phylogenetics
Evolutionary biology
Molecular biology
Genetics
Epidemiology

37. Performing biological Investigations
Most scientists use the metric system when collecting data and performing experiments.

38. Safety
Scientists working in a laboratory or in the field are trained to use safety procedures when carrying out investigations.
Careful preparation is the key to staying safe during scientific activities.
The single most important safety rule is to always follow your teachers instructions.