Introduction to Biology and Chapter 1

What it will take to succeed You will need to read your textbook, take notes, pay attention in class, do assignments (which includes answering questions in the textbook), study until you understand and can answer questions on the material, and prepare for quizzes…. Whew! That sounds like an awful lot of work! 1-2

Why so much work? We learn only 10% of what we read, and 20% of what we hear We have to do more to learn more In biology we are going to be covering some complex topics: for example we will start with a quick review of basic and organic chemistry, move into cell biology, and then go into enzymes, respiration, and photosynthesis. These topics cannot be learned well by simply listening to lectures. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1-3

Memory Tip Memory researcher Robert Bjork “The typical college student spends far too much time reading and underlining and far too little time summarizing, paraphrasing, and testing his or her ability to retrieve what has been studied” Inputting and encoding vs retrieval and outputting of information Testing has to do with retrieval and outputting of information so don’t forget this important step when you are studying Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1-4

Some tips Bring textbook to class Take notes; rework them after class to clear up anything that is unclear. Look at a classmates notes as well as your own. Have a study buddy. Get their phone number so you will have someone to call if you have to miss class. Power points will be posted on my wikispace before the exam: Take advantage of this resource Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Learning Styles Visual Learners: draw diagrams and chart concepts Auditory Learners: listen to lecture tapes Kinesthetic or Tactile Learners: learn from models and specimens, learn by doing Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1-6

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1-7 Why a Study of Biology is Important To be an informed citizen An understanding of biology is important to address a number of social issues today. DNA testing Birth control Global warming AIDS

Biology- is the study of living and once-living things. Bio- means life and –ology means the study of. Who uses Biology? Can you (class) name different people who use Biology in life? Ex. Beekeeper, crime lab technicians, optometrists, farmers.

The Characteristics of Living things 1. Made of one or more cells 2. Displays organization 3. Grows and develops 4. Reproduces 5. Responds to stimuli 6. Requires energy 7. Maintains homeostasis 8. Adaptations evolve over time

The Study of Life  Living things are made of one or more cells.  Cells are the basic unit of structure and function in all living things. One or more cells

 Specialized cells are organized into groups that work together called tissues. Displays Organization The Study of Life  Living things also display organization, which means they are arranged in an orderly way.  Tissues are organized into organs.  Organ systems work together to support an organism.

Grows and Develops The Study of Life  Growth results in the addition of mass to an organism and, in many organis ms, the formation of new cells and new structures.

Reproduces The Study of Life  A species is a group of organisms that can breed with one another and produce fertile offspring.

Responds to Stim uli The Study of Life  Anything that is part of the internal or external environments and causes some sort of reaction by the organism is called a stimulus.  The reaction to a stimulus is a response. Venus flytrap

Requires Energy The Study of Life  Living things get their energy from food.  Most plants and some unicellular organisms use light energy from the Sun to make their own food and fuel their activities.  Organisms that cannot make their own food get energy by consuming other organisms.

Maintains Homeostasis The Study of Life  Regulation of an organism’s internal conditions to maintain life is called homeostasis.  If anything happens within or to an organism that affects its normal state, processes to restore the normal state begin.

Adaptations Evolve Over Time The Study of Life  An adaptation is any inherited characteristic that results from changes to a species over time.

The Methods of Biology Much of the work in Biology is to solve problems. Scientists use the scientific method to solve problems. The following steps are used to solve a problem: recognizing the problem researching the problem forming a hypothesis testing the hypothesis drawing a conclusion

*Scientific Method Identify question Form testable hypothesis Consult priorCollect data to test hypothesisIf hypothesis is knowledge rejected Interpret results Report for peer review Publish findings Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1-21

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display Constructing Hypotheses Once the question is asked, scientists propose answers. These answers are hypotheses. Hypotheses must: be logical account for all current information be testable make the least possible assumptions

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Testing Hypotheses Hypotheses need to be tested to see if they are supported or disproved. Disproved hypotheses are rejected or modified. Hypotheses can be supported but not proven. There are several ways to test a hypothesis: Gathering relevant historical information Make additional observations from the natural world. Experimentation

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Experimentation An experiment is a re-creation of an occurrence. It tests whether or not the hypothesis can be supported or rejected. Experiments must be controlled. This means that all aspects except for one variable must be kept constant. They usually include two groups. Experimental group: variable is altered Control group: variable is not altered

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display Experimental Design The variable that is altered is called the independent variable. (What we are changing) Experiments should have only one independent variable. The variables that change in response to the independent variable are called dependent variables. Changes in the dependent variables are documented as data. (What we are measuring) Data from the experiment is analyzed and hypotheses are rejected and revised or supported.

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display Experimental Data Experiments must: use large numbers of subjects or must be repeated several times (replication). be independently reproducible. The validity of experimental results must: be tested statistically. be scrutinized by other scientists. If the hypothesis is supported by ample experimental data, it leads to a theory.

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display *Theory A theory may be defined as a widely accepted, plausible general statement about a fundamental concept in science. The germ theory states that infectious diseases are caused by microorganisms. Many diseases are not caused by microorganisms, so we must be careful not to generalize theories too broadly. Theories continue to be tested. Exceptions identified Modifications made

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display A Scientific Law A scientific law is a uniform and constant fact of nature that describes what happens in nature. An example: All living things come from pre-existing living things. Scientific laws promote the process of generalization. Inductive reasoning Since every bird that has been studied lays eggs, we can generalize that all birds lay eggs. (IGA) Once a theory becomes established, it can be used to predict specific facts. Deductive reasoning We can predict that a newly discovered bird species will lay eggs.

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display Scientific Communication Data is shared with the scientific community through research articles published in scientific journals. These articles are scrutinized by other scientists before they are published. Scientists present preliminary data at conferences. Scientists collaborate

Quantitative Research Formal, objective, systematic process in which numerical data are used to obtain information about the world Data obtained is then used to produce graphs or tables to communicate findings

International System of Units or SI system- is a measuring system based on units of 10. Length- is the distance from one point to another. The SI unit of length is the meter (m). One penny is the smallest unit of money. Millimeters are the smallest unit of measurement. SI Units

Measurements Used in Biology 40 kilometers to the nearest city -2-liters of soda -a bag of potato chips weigh 184 grams -35 millimeter camera -medicine comes in 25 –milligram tablets

How are metric units grouped PrefixSymbolMeaning Kilok1000 Hectoh 100 Dekada 10 Decid 0.1 (1/10) Centic 0.01 (1/100) Millim (1/1000)

Volume- is the amount of space a substance occupies. If you multiple length by width by height = volume. Example would be soft drinks. One liter equals 1000 milliliters (mL).

Weight and Mass Weight is a measure of the force of gravity on an object. Mass is how much matter is in something. The instrument to measure mass is a balance. The unit to measure mass is the kilogram (kg). Grams are used to measure small objects.

Time and Temperature Time is the period between two events. Time is measured in seconds. Temperature is the amount of heat in something. The Kelvin scale (K) is used in science. Scientists use Celsius because it’s easier to use. Freezing point is 0 and boiling is 100 degrees.

Descriptive Research Is used to describe characteristics of a population or phenomenon being studied. (involves observing the subject) It answers questions about how/when/why the characteristics occurred Examples: how animals react to changes in their environment