Chapter 01 Lecture Outline See separate PowerPoint slides for all figures and tables pre-inserted into PowerPoint without notes. Copyright © 2016 McGraw-Hill Education. Permission required for reproduction or display.

Exploring Life and Science See separate FlexArt PowerPoint slides for all figures and tables pre-inserted into PowerPoint without notes 2

Points to ponder What is biology? What characterizes life? How do we classify life? Where do humans fit into the big picture? How do we study science? Where is scientific information published and what should you be aware of?

What characteristics are shared by living organisms? 1.1 The Characteristics of Life What characteristics are shared by living organisms? Organized from the atom to the biosphere Use materials and energy from the environment Maintain a relatively constant internal environment (homeostasis) Respond to internal and external stimuli Reproduce and grow Have an evolutionary history through which organisms change over time

How are living things organized? 1.1 The Characteristics of Life How are living things organized? Biosphere Regions of the Earth’s crust, waters, and atmosphere inhabited by living things Ecosystem A community plus the physical environment Community Interacting populations in a particular area Population Organisms of the same species in a particular area Organism An individual; complex individuals contain organ systems nervous system shoot system Organ System Composed of several organs working together brain leaf Organ Composed of tissues functioning together for a specific task nervous tissue photosynthetic tissue Tissue A group of cells with a common structure and function neuron plant cell Cell The structural and functional unit of all living things Molecule Union of two or more atoms of the same or different elements Figure 1.2 Levels of biological organization. Atom Smallest unit of an element composed of electrons, protons, and neutrons

How do we classify humans? 1.2 Humans Are Related to Other Animals How do we classify humans? Human House cat Domain Eukarya Eukarya Kingdom Animalia Animalia Phylum Chordata Chordata Class Mammalia Mammalia Order Primates Carnivora Family Hominidae Felidae Genus Homo Felis Species sapiens domesticus

What distinguishes humans? 1.2 Humans Are Related to Other Animals What distinguishes humans? Cultural heritage or patterns of our behavior passed from one generation to the next Highly developed brains Completely upright stance Creative language skills Varied tool use Modification of our environment for our own purpose which may threaten the biosphere

What do we know about science? 1.3 Science as a Process What do we know about science? Science is a way of knowing about the natural world. Science and scientists should be objective. Scientific conclusions may change or be modified as our understanding and technology increase. Science is studied using the scientific method.

Scientific theories in biology 1.3 Science as a Process Scientific theories in biology

The steps of the scientific method 1.3 Science as a Process The steps of the scientific method Start with an observation Develop a hypothesis Make a prediction and perform experiments Collect and analyze data Develop a conclusion

The steps of the scientific method 1.3 Science as a Process The steps of the scientific method Figure 1.7 The scientific method.

A controlled study Variables Groups 1.3 Science as a Process A controlled study Variables Experimental variable is the variable that is purposely changed or manipulated. All other variables need to remain constant. Groups Test group is a group of subjects that are exposed to the experimental variable. Control group is a group for comparison that is not exposed to the experimental variable.

A controlled study in action 1.3 Science as a Process A controlled study in action Figure 1.9 A controlled laboratory experiment to test the effectiveness of a medication in humans.

1.3 Science as a Process How the cause of ulcers was discovered: The scientific method in action Observations: Many patients had a particular bacterium near their ulcers. Hypothesis: Helicobacter pylori is the cause of gastritis and ulcers.

1.3 Science as a Process How the cause of ulcers was discovered: The scientific method in action Experiment/observations: 1st – H. pylori was isolated and grown from ulcer patients. 2nd – Humans swallowing a H. pylori solution developed inflammation in their stomachs. Conclusion: H. pylori was the cause of most ulcers and can be cured by antibiotics.

Reading about scientific information 1.3 Science as a Process Reading about scientific information Scientific journals are considered the best source of information but can be difficult for the lay person to understand. Often the lay person reads secondary sources and must be wary of information taken out of context. Be careful of information on the Internet by using reliable sources such as URLs with .edu, .gov and .org.

What should you look for when you read about science? 1.4 Making Sense of a Scientific Study What should you look for when you read about science? Beware of anecdotal data. Understand methodology and results. Does the data justify the conclusions inferred by the scientists? Be able to read a graph. Have some understanding of statistics.

Reading a graph What information does this line graph convey? 1.4 Making Sense of a Scientific Study Reading a graph What information does this line graph convey? Figure 1.10 The presentation of scientific data.

Does science have social responsibilities? 1.5 Challenges Facing Science Does science have social responsibilities? Science is a way of acquiring knowledge about the natural world. It is a slightly different endeavor than technology.

Does science have social responsibilities? 1.5 Challenges Facing Science Does science have social responsibilities? Technology is the application of scientific knowledge to human interests. Bioethics is the branch of ethics concerned with the development and consequences of biological technology. Genetic engineering (genetically modified crops) Threat to biodiversity

Human Influence on Ecosystems 1.5 Challenges Facing Science Human Influence on Ecosystems Humans tend to modify ecosystems for their own purposes. Changes in human behavior and use of new technology can result in new diseases (emerging diseases). Human activities may attribute to climate change (global warming).