The Scientific Study Of Life Chapter 1

Objectives n Outline the universal characteristics of living things n Describe the Scientific Classification System n Outline the Scientific Method as a process

Chapter 1 Page1 n Biology is the study of life n Living organisms have several properties and common characteristics u Exhibit order u Ability to reproduce u Ability to grow and develop u Utilization of energy ( metabolism) u response to external environmental stimuli u Ability to adapt

Chapter 1 Page2 n Living organisms have several properties and common characteristics con’t u Maintenance of homeostasis u Homeostasis maintains living systems in an acceptable range

Chapter 1 Page 3 n Cell: most basic structure in living organisms, capable of carrying out all of the activities fundamental to life n Cell is the structural and functional unit of life n Robert Hooke, an English Scientist, First described and named cells in n There are two main types of cells: Prokaryotes and Eukaryotes

Chapter 1 Page 4 n Characteristics of Prokaryotes u bacteria u lack many of the organelles of eukaryotes u smaller u many have cell walls

Chapter 1 Page 5 n Characteristics of Eukaryotes u plants, animals, fungi, protista u membrane bound well defined nucleus u complex organelles u cell wall only in plants

Prokaryotes Vs Eukaryotes

Chapter 1 Page 6 n Cells are organized in tissues, u organs, u organ systems, u individuals, u populations, u communities u and ecosystems

Chapter 1 Page 7 n Biologists classify organisms into groups with similar characteristics to understand the diversity of life n Classification of organisms = taxonomy n The system progresses from the most general to the most specific

Chapter 1 Page 8 The “system” 4 Kingdom 4 Phylum 4 Class 4 Order 4 Family 4 Family 4 Genus 4 Genus 4 Species 4 Species

TheSystem n Based on information obtained the System has been modified and is much more complicated than we will take time to explain in our class. n There are now several Domains above the Kingdom Level – Please read about them

Chapter 1 Page 9 n For our purposes we will discuss the Five Basic Kingdoms: u Monera = Bacteria u Protista = unicellular eukaryotes u Plantae = plants u Fungi = mushrooms, slime molds, fungi u Animalia = animals

Chapter1 Page 10 n Science means to know in Latin n Scientific Method specifies a process used to find answers n there are many different approaches

Chapter1 Page 11 n Scientific Process ( Method) u Review accumulated scientific data u Formulate hypothesis u Experiment and observe to collect data u Evaluate results

Chapter1 Page 12 n Facts to remember regarding hypotheses u They reflect past experience with similar questions u Propose multiple hypotheses whenever possible u Hypotheses should be testable via scientific process u Hypotheses can be eliminated, but not proven with 100% certainty

Hypotheses Con’t n H 0 n H 0 = There is no difference n n Example: There will be no difference in the stalking behavior of lions born in zoos and lions born in the wild n n H A = There is a difference n n Example: Lions born in the wild will stalk prey more efficiently than those born in zoos.

Positive and Negative Feedback n Used to regulate function in many biological systems n Prevents was of energy and biochemicals in living systems n Helps maintain homeostasis

Positive and Negative Feedback