Chapter 1 Notes

What is Biology? Biology is the study of life and living things. Ex. Structures and functions of living things Relationships among living things History and origins of living things

What are some of the things scientists do? Study the diversity of life Research diseases Develop technologies Improve agriculture Preserve the environment

Living things An organism is something that has or once had all of the characteristics of life. There are 8 characteristics

1. Made of one or more cells

2. Displays organization Ex. Organ systems and specialized body parts

3. Grows and develops Growth- results in addition of mass to an organism, new cells and structures Develop- process of natural changes that take place during life

4. Reproduces Reproduction- production of offspring *not essential to all organisms

5. Responds to stimuli Stimulus- anything that triggers a response Response- the reaction Ex. Pupils dilating in dim light and Venus fly traps catching food

6. Requires energy

7. Maintains homeostasis Homeostasis- regulation of ones internal conditions to maintain life Ex. Sweating to cool down and maintains blood glucose levels

8. Adaptations evolve over time Adaptation- any inherited characteristic that results from changes over time Ex. Darwin’s finches

What is science? The knowledge based on the study of nature and its physical settings Ex. Biology, chemistry, physics, ornithology The purpose of science is scientific inquiry that seeks to develop explanations.

Scientific inquiry is both a creative process and a process rooted that involves unbiased observations and experimentation. Theory- an explanation of a natural phenomenon supported by evidence The two most important theories in biology are the cell theory and theory of evolution.

Pseudoscience imitates science and is based on beliefs. Some examples of pseudoscience are physiognomy, astrology, palmistry, and psychic readings. There are no science-based explanations to provide evidence for the natural world.

Constant reevaluation of what is known leads to more questions and additional research. New knowledge from research is gained that scientists then evaluate. Sciences advance by accommodating new information as it is discovered.

Scientists welcome debate about another’s ideas Scientists welcome debate about another’s ideas. Scientific advances are made by accommodating new information. An example of this is the research on diseases such as HIV and AIDS. Science questions results. An example of this is the classification of bats which are classified as mammals rather than birds based on similar traits.

Science tests claims with conclusions being based on evidence, while pseudoscience is based on both fact and opinion.

Before it is made public, science-based information is reviewed by scientists’ peers. This is called peer-review.

Scientists use the metric system which is based on the powers of ten. Ex. meters, grams, liters This system is called the International System of Units, or SI.

Science in everyday life There has been a world wide fascination with science lately. An example of this is popular television programs about crimes and based on forensics to solve these crimes. Many other advances include cloning, stem cell research, and nuclear power.

In order to evaluate or make decisions regarding issues such these topics, we must all be science literate.

Ethics is a set of moral principles or values held by a society. Ethical issues must be addressed by society based on the values it holds important.

Science inquiry involves asking questions and processing information from a variety of reliable sources. This is followed by making logical conclusions called inferences.

The Scientific Method Ask a question Gather information Form hypothesis Perform experiment Observe experiment Record data Report conclusion

Scientists use scientific methods but not in the same way each time. Observations and inferences happen throughout the process.

A hypothesis is a testable explanation of a situation. When a hypothesis is supported by data from additional investigations, usually it is considered valid and is accepted by the scientific community.

Serendipity is the accidental or unexpected but fortunate results. ex. The antibiotic, penicillin, is an example of this.

In 1928 while organizing a pile of petri dishes in the sink where he had been growing bacteria, Fleming opened each dish and examined it before dropping it into the cleaning mixture. A particular one caught his attention. Mold was growing on one of the dishes, which was supposed to happen, but he discovered that it had contaminated a staphylococcus culture and stopped the bacteria's growth. It fact, it had actually killed it. After taking a sample of the mold, he found that it was from the penicillium family. He named it penicillin and found that it was nontoxic and sufficient in treating many types of bacteria harmful to man.

Scientists conduct experiments in controlled settings that tests hypotheses. When a biologist conducts an experiment, he or she investigates a phenomenon in a controlled setting to test a hypothesis.

The control group in an experiment is a group used for comparison. The experimental group is the group exposed to the factor being tested.

The factor that is changed in an experiment is the independent variable. Only one factor in a controlled experiment can change at a time. As a result of this change, the dependent variable is the one measuring the effect of the change. A constant remains fixed during the experiment.

Scientists gather data which is information gained from their observations. This data is analyzed by asking “Has the hypothesis been supported?” Biologists report their conclusions in scientific journals.

Qualitative data are descriptions of what our senses detect. Data Gathering Quantitative data can be measurements of time, temperature, length, mass, area, volume, density, or other factors. Qualitative data are descriptions of what our senses detect.

Safety symbols will be used in biology labs to alert you to possible danger. Poison Explosive Biohazard Flammable Radioactive