The Science of Biology Chapter 1

Group #1 The characteristcs that all living things have in common are: 1. Cellular organization- all organisms consist of one or more cells. 2. Order- all organisms consist of one or more cells with highly ordered structures. 3. Sensitivity- all organisms respond to stimuli 4. Growth, development & reproduction 5.Energy utilization- all organisms take in energy and use it to perform many kinds of work 6.Homeostasis- ability to maintain a constant internal environment 7.Evolutionary adaption- all organisms interact with other organisms and their environments

Group #1 Compare & contrast deductive and inductive reasoning. (Give an example of each) 1.Deductive- applies general principles to predict specific outcomes. Ex: using geometry to correctly deduce the circumference of the Earth. 2. Inductive- uses specific observations to construct general scientific principles. Ex: Newton observed an apple, when released, falls to the ground. Inferred…all objects fall toward the center of the Earth. What is a hypothesis? A hypothesis is a suggested explanation that accounts for certain observations. A proposition that might be true.

Group #1 Why are experiments, with relation to hypotheses, so important to science? Experiments can prove hypotheses to be true or false.

Group #2 Explain what is meant by a variable and a control A variable is a factor that could influence a particular process or outcome. A control is a factor that remains constant. How do predictions differ from hypotheses? How do predictions and inferences differ? A hypothesis is a testable statement based on an observation. Ex: if a plant receives fertilizer, then it will grow bigger than on that does not. A prediction is statement about what is going to happen. (usually during the experiment) An inference is a conclusion based on an observation. Ex: your doorbell rings…..?????

Group #2 Describe what is meant by a theory in science. Discuss why a theory, to the general public, is not scientific fact A theory is a time tested, data supported explanation for some aspect of the natural world. The general public confuses a theory with a hypothesis. Many times you hear people say…… “I have a theory” Why is the construction of models important in biology? Models provide a way to organize how we think about a problem. They can give us a closer look at the bigger picture.

Group #3 How does basic research differ from applied research? Basic research is intended to extend the boundaries of what we know. Applied research refers to the scientific study used to solve practical problems. What does Darwin’s theory of evolution attempt to explain? How organisms on Earth have changed over time and acquired a diversity of new forms.

Group #3 How did Darwin explain the similarity of plants and animals found on the Galapagos Islands with those of South America? Lands with similar climates have unrelated plants & animals, indicating that diversity is not entirely influenced by climate and environment. What is the theory of natural selection? Give an example. The differential reproduction of genotypes, caused by factors in the environment, which lead to evolutionary change. Ex: peppered moth

Group #4 How did Malthus explain population growth? Populations of plants and animals (including humans) increase geometrically while humans ability to increase food supply is arithmetically. How did the work of Malthus impact Darwin’s theory of evolution? Although every organism has the potential to produce more offspring than can survive, only a limited number actually do survive and produce further offspring.

Group #4 How does artificial selection differ from natural selection? Provide an example of each. Natural selection means that nature plays a role in selecting which offspring survive. Ex: peppered moth Artificial selection is a process in which humans intervene. They pick the best breeds to produce certain characteristics. Ex: dogs How did the work of Alfred Wallace impact Darwin’s theory? Wallace worked on the theory of evolution independently from Darwin. Wallace sent Darwin an essay on his work which pushed Darwin to finish his manuscript.

Group #5 How did the fossil record contribute to Darwin’s theory? The fossil record does support the theory of evolution because it shows a graded series of changes in form with the evolutionary parade visible for all to see. Why was Darwin convinced that the Earth was much older that physicists of his time believed? Fossils found from extinct species resemble species living in modern day. Progressive changes in characteristics can be seen in fossils from earlier and earlier layers of rock.

Group #5 How do comparative anatomy studies support Darwin’s theory? Homologous structures are similar in origin, but differ in structure and function. Ex: arm in human and forelimb in cats. Analogous structures are similar in structure and function, but differ in origin. Ex: wings of birds & butterflies. Both are used to show evolutionary relationship among organisms. Explain how the science of genetics supports Darwin’s theory. Genetics accounts for the production of new variations in organisms which is a critical requirement to Darwin’s theory.

Group #6 How does the molecular basis of inheritance explain the continuity of life? Continuity of life depends on the faithful copying of a cell’s DNA into daughter cells. Explain the relationship between structure and function in living systems. When we know the function of a particular structure, we can infer the function of similar structures found in different contexts, such as different organisms. Ex: we know the structure of human’s cell surface receptor for insulin; we then find a similar molecule in the membrane of a cell from a different species. We might discern the evolutionary relationship between the two species.

Group #6 Explain how the diversity of life is due to evolution. The underlying unity of biochemistry and genetics argues that all life has evolved from the same origin event. What is meant by “living systems exist in a nonequilibrium state”? Living systems are open systems that function far from thermodynamic equilibrium. A constant supply of energy is needed to maintain a stable nonequilibrium state. Ex: state of nucleic acids and proteins in all your cells: they would not be polymers at equilibrium, they would be hydrolyzed to monomers.