Evolution

Bellringer  1. What part of an experiment is not changed and serves as the standard for comparison?  2. What variable is graphed on the x-axis?  3. Why should you only change one variable in an experiment?  4. How should you write a hypothesis?  5. What variable do you (the scientist) change?

Answer  1. Control Group  2. Independent Variable  3. If you change more than one variable, then you will not know for certain the cause of your experimental results. For example, if you wanted to test how the amount of water affected plant height, but also exposed them to different amounts of sunlight, you would not know if your height variation was because of the differing amounts of water or of sunlight.  4. If/Then statement that is testable  5. Independent Variable

Bellringer  6. Which level of organization is the pancreas?  7. Which level of organization is a mitochondrion?  8. Why does the structure of a human skin cell differ from that of a human muscle cell?  9. If you repeat an experiment and the results are very different from the results you got the first time, what would your next steps be?  10. What is homeostasis?

Answers  6. Organ  7. Organelle  8. The structure of each cell is related to its function. Muscle cells and skin cells have two different functions so are structured differently.  9. Repeat the experiment again to see if the results stay consistent or are inconsistent.  10. Maintaining the internal conditions of an organism (such as temperature, pH, metabolism, etc.)

Bellringer  11. What are the steps of the scientific method (or the stages of scientific thinking)?  12. What is the purpose of graphing experimental data?  13. What is the difference between a research question and a question for scientific experimentation?  14. Which SI unit is appropriate to measure the mass of a fruit fly?  15. Which SI unit is appropriate to measure the length of Eagle Way (the road that circles the entire town)?

Answers  11. Make observations and ask questions, formulate a hypothesis, test your hypothesis, analyze data, evaluate results (and repeat)  12. To see the trend in the data and more easily analyze and share your results  13. A research question is one that you find the answer to by looking at other people's experiments and investigations on the topic. A question for experimentation is one stated in a way that you can set up an experiment to find the answer. You should be able to find the independent and dependent variables in the question.  14. milligram  15. kilometer

Lamarck vs. Darwin  Step 1: Copy this chart onto a piece of paper What Darwin BelievedHow they agreedWhat Lamarck Believed Why do we believe Darwin?

Individual Work  Step 2:  Individually read about the person you are assigned. 1’s read about Lamarck; 2’s read about Darwin.  Annotate your article and write at least 4 main points about the person in the appropriate column  10 minutes

Now pair up  Step 3:  Find a person who read about the same person as you and sit by them.  Take 5 minutes to compare your notes and add any they have that you don’t to your column.

Alternate View  Step 4:  You two find a group of two that read about the other scientist.  Sit as a group of 4 and compare scientists  Discuss each scientist’s views and fill in the other two columns in the middle of your chart  10 minutes

Time to Share Our Thoughts.....

Why we believe Darwin  Step 5:  With your group of 4 read the two paragraphs with the heading Why We Believe Darwin  Annotate the reasons in your article and write them in the bottom column on your paper  Come to a consensus on your answer and write it on the big piece of paper on the side wall  15 minutes

Questions:  What is natural selection?  Is it a fact or a theory? Explain your answer.  What science was developed later which was found to support Darwin’s theory?  What are the specific clues that most clearly distinguish a Darwinian explanation from a Lamarckian explanation?  Do you think there is any similarity in the theories proposed by the two scientists? Explain.

Bellringer Answers What type of bonds are most common in living organisms? Covalent 2.What is the difference between an ion, isotope, and element? Ions have gained or lost an electron. Isotopes have a different number of neutrons than the element but the same number of protons. 3.What are the parts of a chemical reaction? Reactants and products 4.What is the difference between organic and inorganic compounds? Organic compounds contain carbon and were once living. 5.What are the pH ranges for acids? Bases? Neutral substances? Acid: 0-6; Neutral: 7; Base: 8-14

Bellringer Answers – 6 – 10 o What happens to H+ as pH increases? OH- as pH increases? H+ decrease by a factor of 10; OH- increase by a factor of 10 o Describe the properties of water? High boiling point, bonded by H bonds, high specific heat, polar covalent molecules, causes surface tension, adhesion (water sticks to other things) and cohesion (water sticks to water), and water becomes less dense when it freezes (ice floats on water). o Name the 4 major macromolecules and a functional group related to each one. Carbohydrates – alcohols, ketones, and aldehydes; Lipids – carboxyl; Proteins – amino groups, carboxylic acid groups, thiol groups; Nucleic Acids – phosphate group. o Name the monomers of each macromolecule. Carbohydrate – monosaccharide; Lipid – fatty acid; Protein – amino acid; and Nucleic Acid – nucleotide. o Describe the function of enzymes and how their activity can be altered. Enzymes speed up chemical reactions by decreasing the activation energy. They can be altered by acids, bases, salts, and excessive heat.

Bellringer: Questions What is the basic energy compound of living things? ATP (adenosine triphosphate) 2.Where is energy stored in ATP? Produced by metabolizing food and the energy is in the phosphate- phosphate bonds. 3.If the pH changes from 3 to 5, what has happened to the H+ concentration? Decreases by 100X 4. Which particle of an atom of an element determines whether it will be unstable and radioactive? Neutron 5.What type of bonds hold the nitrogenous bases together in DNA? hydrogen