Biology - Chp 1 - Biology The Study Of Life - PowerPointPresentation Transcript
Get a packet from the desk in the back of the room and write your name on it.
In your notebooks write the date in the margin and the following Do Now assignment
What is it that you think makes something alive?
Chapter 1 Biology: The Study of Life
Section 1.1 What is Biology?
The Science of Biology
People have always been curious about living things
The concepts, principles, and theories that allow people to understand the natural environment form the core of Biology
The study of Life
Bio logy (greek) Life Study of
Biologists study the interactions of life.
Biologists study the diversity of life.
Throughout your study of biology you will come to appreciate the great diversity of life on Earth
Biologists study the interactions of the environment.
No living thing exists in isolation
The study of biology includes the investigation of living interactions
The study of one living thing always involves the study of the others in which it interacts
Ex.) studying wild rats means you have to study what it eats and what eats it
Biologists study problems and propose solutions.
Disease prevention (humans and other organisms)
Endangered species prevention
Where are all the bees?
Characteristics of Living Things
Biologists have formulated a list of characteristics by which we can recognize living things
Anything that possess all the characteristics of life
1. Living things are organized
All organisms are composed of one or more cells which contain the genetic material or DNA that provides all the information needed to control the organisms life processes
2. Living things make more living things
The production of offspring
Reproduction is not essential for the survival of an organism, but it is essential for the continuation of the organisms species
A group of organisms that can interbreed and produce fertile offspring in nature
3. Living things change during their lives
An increase in the amount of living material and the formation of new structures
All the changes that take place during the life of an organism
4. Living things adjust to their surroundings
An organisms surroundings
Ex.) air, water, weather, temperature, other organisms in the area
Anything in an organisms external or internal environment that causes the organism to react
A reaction to a stimulus
Regulation of an organisms internal environment to maintain conditions suitable for survival
Ex.) Body temp regulation, water, minerals
Without this ability to adjust to internal changes, organisms die
The ability to cause change
Organisms get their energy from food
5. Living things adapt and evolve
any structure, behavior, or internal process that enables an organism to respond to environmental factors and live to produce offspring
Anything that makes an organism better at life
How Adaptations Work
Adaptations are inherited from previous generations
There are always some differences in the adaptations of individuals of a population
As the environment changes, some adaptations are more suited to the new conditions than others
Individuals with more suitable adaptations are more likely to survive and reproduce
As a result, individuals with these adaptations become more numerous
The gradual change in a species through adaptations over time
Clues to the way present diversity of life came about may be understood through the study of evolution
As we learn more about Earth’s organisms in this course, take time to reflect on the general characteristics of life
Rather than simply memorizing facts about organisms or the vocabulary terms, try to see how these facts and terms are related to the characteristics of living things
Finish answering questions on page 4. I would like to go over the answers in about 3 minutes.
Section 1.2 The Methods of Biology
Why does rain bring out the worms?
Observing and Hypothesizing
Curiosity is often what motivates biologists to try to answer simple questions about everyday observations
The knowledge obtained when scientists answer questions provides better understanding of general principles or may lead to practical applications or may lead to new questions
The Methods Biologists Use
The common steps that scientists use to gather information and answer questions
Scientific methods usually begin with identifying a problem to solve
The Story of the Brown Tree Snake
An explanation for a question or a problem that can be formally tested
A hypothesis is not a random guess!
The scientist has some idea of what the answer might be through personal observations, extensive research, or previous investigations
An investigation that tests a hypothesis by the process of collecting information under controlled conditions
What is a controlled experiment?
Some experiments involve two groups: the control group and the experimental group
The group in which all conditions are kept the same
The test group in which all conditions are kept the same except for the single condition being tested
Does fertilizer help plants grow taller? Water + Fertilizer Water
Designing an experiment
In a controlled experiment, only one condition is changed at a time
Does fertilizer help plants grow taller? Water + Fertilizer Water
Same volume of water
Same sun exposure
The condition in an experiment being changed
The condition that results from a change in the independent variable
Growth (centimeters) Fertilizer No Fertilizer Does fertilizer help plants grow taller?
Now You Try…
A number of rats are divided into two groups: One group is fed a normal diet, whereas the other group is fed the same diet but with one necessary mineral left out. The animals receiving the normal diet remained healthy; those in the other group grew weaker. Formulate a hypothesis based on this experiment.
A scientist conducted an experiment to determine the effect of environment on the color of fur of a Himalayan rabbit. The Himalayan rabbit typically has a white coat except for its colder nose, feet, tail, and ears, which are black. The scientist shaved an area of hair on the back of each rabbit, then placed an ice pack over the shaved area on one rabbit (A).
To carry out investigations, scientists need tools that enable them to record information
Safety is another important factor that scientists consider when carrying out investigations
A symbol that warns you about a danger that may exist from chemicals, electricity, heat, or procedures you will use
To answer their questions about scientific problems, scientists seek information from other investigations
Info obtained from investigations or experimental results
Thinking about what happened
After careful review of the results, the scientist must come up with a conclusion
Was the hypothesis supported by the data?
Was it not supported? Is more data needed?
Does the experiment need to be repeated?
After analyzing the data, most scientists have more questions than they had before the investigation
Results and conclusions of investigations are reported in scientific journals
When a hypothesis that is supported by many separate observations and investigations usually over a long period of time, becomes a theory
An explanation of a natural phenomenon that is supported by a large body of scientific evidence obtained from many different investigations
A theory results from continual verification and refinement of a hypothesis
In addition to theories, scientists also recognize certain facts of nature called laws or principles
Get your homework out (pg 8) and place it on top of your desk so I can check it.
In your notebook, please describe this class in anyway you’d like.
200 carrot seeds each were used in an investigation to test for the influence of temperature on germination of seeds. Group A had 150 seeds and was kept at a temperature of 20 degrees Celcius and Group B had 50 seeds and was kept at 10 degrees Celcius. All other conditions were the same.
Section 1.3 The Nature of Biology
Kinds of Information
Scientific information can usually be classified into one or two main types, qualitative or quantitative
Numerical values are compared
Quantitative data may be used to make graphs or tables
Measurements in the International System
Scientists use a form of the metric system called the International System of measurements or SI
Q: Why is it important that all scientific measurements be done in the same way?
A: Not everyone uses the English system of measurements that we use
Advantage of SI
Only a few basic units
Decimal system, measurements can be expressed in multiples of ten or tenths of a basic unit by applying a standard set of prefixes to the unit
In biology, the metric units you will encounter most often are…
meter gram liter second Celsius
Some phenomena aren’t easily expressed as quantitative information
Science and Society
Some people blame scientists for the existence of controversial things in science
To comprehend the nature of science, people must understand that knowledge gained through scientific research is never inherently good or bad
Society as a whole must take responsibility for the ethical use of scientific discoveries
The moral principles and values held by humans
Can science answer all questions?
No, some questions are simply not in the realm of science
Ex.) good vs. evil, ugly vs. beautiful
These questions cannot be tested using scientific methods
However, this does not mean that these questions are unimportant
The application of scientific research to societies needs and problems
Technology has helped us in many ways
Increase production of food
Decrease the amount of manual labor
Aided in the reduction of wastes and environmental pollution
The advances of technology has resulted in some serious problems too
Too much fertilizer can contaminate water
Automobiles have led to increased air pollution
Science and technology will never answer all of the questions we ask, nor will they solve all of our problems
However, during your study of Biology you will have many of your questions answered, and you will explore new concepts
Don’t forget, you are part of this living world and you can use the process of science to ask and answer questions about that world