1. Introduction to Biology

2. Biology – The Study of Life
Life arose more than 3.5 billion years ago
First organisms (living things) were single celled
Organisms changed over time (evolved)

3. Characteristics of Life
(1) Order
(2) Regulation
(3) Growth and development
(4) Energy processing
Figure 1.4B Some important properties of life.
(5) Response to the environment
(6) Reproduction
(7) Evolutionary adaptation

4. The Unity of Life: All forms of life have common features
1. Complex Organization/Order 2. Regulate internally 3. Growth and development 4. Energy processing 5. Contain DNA 6. Respond to the environment 7. Reproduce 8. Adapt 9. Evolve/Change
Teaching Tips
1. The authors make an analogy between the four bases used to form genes and the 26 letters of the English alphabet used to create words and sentences. One could also make an analogy between the four bases and trains composed of four different types of railroad cars (perhaps an engine, boxcar, tanker, and caboose). Imagine how many different types of trains one could make using just 100 rail cars of four different types. (The answer is 4100.)
2. The seven characteristics of life described in Module 1.4 can easily become another list to memorize. Exercises that require reflection and analysis of these significant traits can help to make this list more meaningful. Consider creating examples of each of these properties for students to analyze and identify.
Copyright © 2009 Pearson Education, Inc.

5. Themes of Biology
Seven Themes of Biology  1. Cellular Organization  2. Reproduction  3. Metabolism  4. Homeostasis  5. Heredity  6. Evolution  7. Interdependence

6. 1. Cell Structure and Function
Biology Theme Descriptions
1. Cell Structure and Function
Cells are basic unit of life
All organisms are composed of and arise from cells

7. Life is organized at both the molecular and cellular levels
Organization
Life is organized at both the molecular and cellular levels

8. In multicellular organisms, cells and groups of cells (tissues) are organized by their function
Tissues  organs
Organs  body systems Body SystemsORGANISM

9. 2 . Homeostasis – maintaining an internal balance despite changes in the external environment.
Organisms must maintain very stable internal conditions to sustain life
Temperature, blood pressure, blood pH

10. 3. Heredity& Reproduction
Organisms must reproduce in order to perpetuate the species.
Organisms transmit genetic information to their offspring -Heredity

11. 4. Reproduction (Growth)
Grow occurs as the result of cell division and cell enlargement
Cell division is the formation of two cells from a preexisting cell
New cells enlarge as they mature

12. 5. Metabolism ALL energy comes from the SUN (directly or indirectly)
Photosynthesis – process plants use to convert solar energy into chemical

13. Metabolism -Sum of all chemical reactions Cellular respiration-
-Breakdown of glucose to generate energy
Photosynthetic organisms -Autotrophs (producers) plants, some bacteria
Heterotrophs- (consumers) animals

14. 6. Interdependence of Organisms
Interaction of organisms with one another and with their environment
Symbiotic relationships
Predator/prey relationships
Food Webs- passage of energy through trophic levels

15. Interdependence Continued..
Life requires interactions between biotic and abiotic components
Organisms respond to stimuli in the external environment
The nonliving components are recycled and used over and over again. Carbon dioxide, oxygen, water, and various minerals are examples of components cycled within an ecosystem.
Student Misconceptions and Concerns
1. Many students enter our courses with a limited appreciation of the diversity of life. Ask any group of freshmen at the start of the semester to write down the first type of animal that comes to mind, and the most frequent response is a mammal. As the diversity of life is explored, the common heritage of biological organization can be less, and not more, apparent. The diverse forms, habits, and ecological interactions overwhelm our senses with striking distinctions. Emphasizing the diversity as well as the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
2. We live in a world that is largely understood by what we can distinguish and identify with our naked senses. However, the diversity of life and the levels of biological organization extend well below the physical scale of our lives. For many students, appreciating the diversity of the microscopic world is abstract, nearly on par with an understanding of the workings of atoms and molecules. The ability to examine the microscopic details of the world of our students (the surface of potato chips, the structure of table salt and sugar, the details of a blade of grass) can be an important sensory extension that prepares the mind for greater comprehension of these minute biological details.
Teaching Tips
1. Consider asking students to bring to class a page or two of some article about biology that appeared in the media in the last month. Alternatively, you could have each student a Web address of a recent biology-related news event to you. You might even have them relevant articles to you for each of the main topics you address throughout the semester.
2. The scientific organization Sigma Xi offers a free summary of the major science news articles appearing each weekday in major U.S. news media. The first paragraph or so of each article is included in the with a hyperlink to the rest of the article. The diverse topics are an excellent way to learn of general scientific announcements and reports. Typically, 5–10 articles are cited in each . To sign up for this free service, go to
3. Help the class think through the diverse interactions between an organism and its environment. In class, select an organism and have the class develop a list of environmental components that interact with the organism. Items in this list will likely fall into living and nonliving categories.

16. 7. Evolution Evolve means to change.
Change occurs as the environment changes selecting favorable characteristics.
These favorable characteristics are known as adaptations
natural selection- “survival of the fittest”

17. Natural Selection Natural selection is the driving force in evolution
Organisms that have favorable traits are more likely to survive and reproduce passing these traits on to future generations