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__1st Quarter Assignments__

10/22 Do questions 1 through 8.
 * 1) 35 4th Chapter - 2nd Section Review Questions (Textbook page 76)

10/21 The heads of the section are in outline form below. Under each heading list the main ideas and facts. Put the appropriate lower case letter in front of each idea or fact like in an outline. II. INTRODUCTION TO CELLS A. CELL DIVERSITY 1. Cell Shape 2. Cell size B. BASIC PARTS OF A CELL 1. Plasma Membrane 2. Cytoplasm Control Center C. TWO BASIC TYPES OF CELLS 1. Prokaryotes 2. Eukaryotes D. CELLULAR ORGANIZATION 1. Colonies 2. True Multicellularity
 * 1) 34 4-2 Outline (Starting page 72 in the textbook)

10/20 Write 1 to 18 on another sheet of paper. Identify each of the cell structures in the figure. 1. ............... 2. ............... 3. ............... 4. ............... 5. ...............
 * 1) 33 **Looking Inside Cells**

Provide the word to complete each statement. 6. ............... are tiny structures that carry out specific functions within the cell. 7. The rigid layer of nonliving material that surrounds plant cells is called ............... . 8. In the cells without cell walls, the ............... forms the outer boundary that separates the cell from its environment. 9. The ............... is a large oval structure that directs all the cells activities. 10. Strands of the genetic material Loki in the nucleus is are referred to as ............... 11. The region between the cell membrane and the nucleus is called the ............... 12. ............... produce most of the energy is cell needs to carry out its functions. 13. A maze of passageways called the ............... carries proteins and other materials from one part of the cell to another. 14. ............... function as factories to produce proteins. 15. ............... process and packages newly formed proteins and other materials received from the ER for shipping to other parts of the cell. 16. Organelles called ............... captures energy from sunlight and uses it to to produce the sugar glucose or the cell. 17. the storage area of a cell is called a ............... . 18. ............... are small, round structures in cells that break down large food particles into smaller ones.

10/19 __Comparing Time Lines__ -
 * 1) 32 Biogenesis & Cell Theory Time Lines

Make two parallel 400 year time-lines and compare them. On one time line, place the events in the development of the theory of biogenesis. On the other time line place the events in the development of cell theory and cell biology.

Why was the importance of Hooke's and Leeuwenhoek's work not realized for 150 years? Comparing the time-lines of the development of cell theory, and biogenesis and the relationship between these theories may help answer the above question. Note how improvements in microscopes corresponds to the development of the two theories. Note where the two theories intersect.

__Biogenesis__: The theory of biogenesis developed as scientists investigated the origins of life. Before the theory of biogenesis was developed, scientists thought that life spontaneously generated from nonliving things. A few crucial experiments were pivotal in discrediting the idea of spontaneous generation.

In 1668 Francisco Redi put decaying meat in some jars, then covered half of them. When maggots appeared only on the uncovered meat, Redi concluded that they had hatched from fly eggs and had not come from the meat.

In 1745 John Needham heated broth sealed flasks. When the broth became cloudy with microrganisms, he mistakenly included that they developed spontaneously from the broth.

In 1768 Lazzaro Spallanzani boiled broth in sealed flasks for a longer time than Needham did. Only the ones he opened became cloudy with contamination.

In 1859 Louis Pasteur disapproved spontaneous generation by boiling broth in S-necked flasks that were open to be air. The broth became cloudy only when the flasks tilted and the broth was exposed to dust in the S-neck. Pasteur also studied the causes of many bacterial diseases and established germ theory.

In 1924 Alexander Oparin hypothesized that energy from the sun, lightning, and Earth's heat triggered chemical reactions early in Earth's history. The newly formed molecules washed into Earth's ancient oceans and became a part of what is often called the primordial soup. (The idea of spontaneous generation returns to the forefront of science.)

In 1953 Stanley Miller and Harold Urey produced amino acids in a laboratory using the conditions similar to Alexander Oparin's hypothesis. But, current theory is that the conditions of the early Earth were much different than this hypothesis.

__Cell Theory and Discoveries in Cell Biology__: 1590 – Two Dutch eye glass makers, Zaccharias Janssen and son Hans Janssen experimented with multiple lenses placed in a tube that made objects in front of the tube appeared greatly enlarged.

In 1665 Robert Hooke (English) publishes a book of microscope observations and establishes the microscope is a scientific tool. He made his observations with a compound microscope that could magnify things 20 to 30 times. In this book Hooke drew the cell walls of dead plant cells. (This book got Leeuwenhoek interested in studying cells.)

In 1674 Anton van Leeuwenhoek (Dutch)systematically studied and described living cells including single cell animals (protists). He made single lensed microscopes that could magnify things 200 to 400 times and discovered the world of microscopic organisms. He also described the bands observed in muscle and the nuclei in the blood cells of fish. How Leeuwenhoek made his lenses died with lenses with an equal resolving power were not produces for over 100 years. The British Royal Society published many of the 500 letters Leeuwenhoek wrote them describing his observations.

In 1830 Joseph J. Lister greatly improved the lenses of compound microscopes. Lenses bend or refract different colors of light different amounts producing a blurred halo effect. Lister combined several weak lenses to reduce the halos of light caused by refraction. Due to this new lens scientist began using microscopes as powerful as Leeuwenhoek's that were much easier to use.

In 1838 Matthias Schleiden (German) made the generalization that all plants are made of cells after examining many plant parts which were made of cells. Schleiden didn't understand how new cells are formed. Schleiden and Schwann talked and reaffirmed each others ideas.

In 1839 Theodor Schwann (German) made the generalization that all animals are made of cells after examining many animal parts which are made up cell's. He further proposed that organisms are made of cells.

In 1855 Rudolf Virchow (German) infers that all new cells come from existing cells. He was a doctor and based this inference on his systematic study of diseases.

In 1857 Kolliker describes mitochondria in muscle.

In 1897 Camillo Golgi describes the Golgi apparatus in cells.

10/16
 * 1) 31 3-1 Section Review Questions Page 71

10/15 Warm Up - Cork Cells and their function in the tree.
 * 1) 30 Study Guide Pages 19 & 20

10/14 Finish #29

10/13 1. Draw a cell with all the organelles inside and label them. 2. Draw each organelle in the left column of a peice of paper. 3. Give the description and function of each in the right column.
 * 1) 29 Organelles


 * 1) 28 Extra

10/9 Test continued

10/8
 * 1) 27 Molecules of Life Test

10/7 Finish #24 Optional Extra Credit Draw the pictures and include their captions. 1. Draw the first two columns of Table 3_1 on page 52 of your textbook. Get familiar with these functional groups. 2. Draw the sucrose molecule on page 53 as an example of a carbohydrate. Note that it is a two simple sugars jointed together. 3. Draw adenosine triphosphate (ATP) on page 54. Note that the energy from removing a phosphate powers cellular reactions. 4. Draw the amino acid in part (b) of figure3-7 on page 56. 5. Draw the enzyme action figure on page 57. 6. Draw a saturated and an unsaturated fatty acid like found on page 59. You can shorten the carbon chains to eight atoms. 7. Draw and label a phospholipid like the ones on page 59.
 * 1) 26 Organic Molecules and Functional Groups

10/6 List the two particles found in the nucleus of an atom and indicate their charge. 1. What will make an atom stable? 2. What is a covalent bond? 3. What is an ionic bond? 4. What is the function of an enzyme? 5. Why is water a polar molecule? 6. What ions form in water naturally? 7. What is an acid? 8. What is a base?
 * 1) 25 Study Guide pages 17 and 18 (Homework if not finished in class.)
 * 2) 24 Matter Test Review Questions (See page 45) (Bring this on test day)

Study for the test: Organic Molecules Test Review (See page 61) Practice finding the answers to these questions in your notes #21. 9.Contrast organic and inorganic compounds. 10.What are functional groups? 11.What are the four classes of organic molecules? 12.What are monosaccharides and disaccharides and which of the four classes are they in? 13.Tell what a polysaccharide is and give an example of one. 14.How are carbohydrates used in organisms? 15.What class of molecules are enzymes in. 16.Lipids are mostly non-polar and contain what? 17.Describe how fatty acids interact with water? 18.What is a triglycerides? 19.What is adenosine triphosphate? 20.What can a mitochondrion do to adenosine diphosphate? 21.How do cellular reactions get energy from adenosine triphosphate? 22.What is a phospholipid and where are they found? 23.How are carbohydrates used by organisms? 24.What atoms are proteins made of? 25.Describe the structure of a protein. 26.Describe the structure of a steroid. 27.How do organisms use nucleic acids? 28.Describe the structure of a nucleic acid. 29.Describe the structure of a nucleotide.

10/5 Finish Assignment #21

10/2
 * 1) 23 Study Guide Pages 15 & 16

10/1 1. __Organic compounds__ are made primarily of carbon atoms. 2. Most __inorganic compound__s don't contain carbon. 3. Carbon atoms have 4 outer electrons and become stable when sharing electrons to make 8. 4. Carbon tends to bond with itself and can form long chains, branched molecule, and molecular rings. 5.Organic molecule have __functional groups__ that react to build structures and are involved in chemical reactions. 6.ATP – adenosine triphosphate – is what the cell uses to get energy. 7.Adenosine diphosphate ADP is changed to ATP in the cytoplasm and mitochondria. 8.The difference between ATP and ADP is one phosphate molecule. 9.Cellular reactions use the energy in ATP by removing one phosphate. 10.Carbohydrates are organic molecules composed of Carbon, Hydrogen and Oxygen in a ratio of about one carbon atom to two hydrogen atoms to one oxygen atom. 11.Some carbohydrates make up structures and others are use for storing energy. 12.Monosaccharides are simple sugars. 13.Glucose, fructose and galactose are three simple sugars. 14.Two monosaccharides can combine to form a disaccharide. 15.Three or more monosaccharides combined are called a polysaccharide. 16.Proteins are organic molecules mainly made of carbon, hydrogen, oxygen, and nitrogen. 17.Proteins are composed of subunits called amino acids. 18.There are 20 different amino acids that all share the same basic structure. 19.The differences between amino acids occurs in what is called an “R group.” 20.Peptide bonds connect amino acids into long chains called polypeptides. 21.Proteins are made of one or more folded polypeptides. 22.Enzymes are proteins or RNA that catalyze reactions in cells. 23.Enzymes usually have an optimal operating temperature and pH. 24. Lipids are large energy containing molecules that don't dissolve in water. 25. Lipids include triglycerides, phospholipids, steroids, and waxes. 26. Fatty Acids contain long chains of carbon atoms with a carboxyl group at one end. 27. The carboxyl end of fatty acids are attracted to water(hydrophilic) but the carbon chains are not (hydrophobic). 28. Saturated fatty acids have two hydrogens attached to most of their carbons. 29. Unsaturated fatty acids have only one hydrogen attached to many of their carbon atoms. 30. A triglycerides is composed of three molecules of fatty acids joined to one molecule of the alcohol glycerol. 31. Fats, waxes, and phospholipids are made of triglycerides. 32. Phospholipids make up membranes and have two fatty acid chains instead of three like triglycerides. 33. Steroids are composed of fatty acids fuse into four rings. 34. Nucleic acids are large complex organic molecules that store and transfer important information in the cell. 35. Nucleic acids are made of nucleotides. 36. nucleotides have three parts: a sugar, a phosphate group, and a nitrogenous base. 37. The nucleic acid, DNA contains all the genetic information for cell activities. 38. The nucleic acid, RNA plays many key roles in the building of proteins and can act as an enzyme.
 * 1) 21 Basic Biochemistry Notes

9/30 Test (#22)

9/28 & 9/29 What are the steps of the scientific method? 1. Stating a problem, gathering information, forming a hypothesis, experimenting, analyzing the data, and drawing conclusions is the scientific method. What is a hypothesis? 2. A hypothesis is a proposed explanation or prediction that can be tested. What is a theory? 3. A theory is an explanation based on the results of many observations or experiments. Compare and contrast a theory with a hypothesis. 4. A theory is an explanation based on many observations; a hypothesis is a testable prediction. What is an experimental variable? 5. A variable is something that can change in an experiment. Why is it important to allow only one variable to change at a time during an experiment? 6. Experiments should only test one variable because if two are changed, one doesn't know which variable caused the result. What is an independent variable? 7. The independent variable is what the experimenter changes or enacts in order to do the experiment. What does the experimenter manipulate in an experiment? 8. The experimenter manipulates the independent variable. What is a dependent variable? 9. A dependent variable is what changes as a result of the independent variable. How is a dependent variable related to the independent variable in an experiment? 10. The independent variable is said to cause an apparent change in, or affect the dependent variable. What is a control in an experiment? 11. A control is a group of subjects or an unchanged situation to which the outcome of a test is compared. What are controlled variables in an experiment? 12. Controlled variables are anything that could influence the dependent variables. Why are controlled variables important in an experiment? 13. Controlled variables must be carefully monitored and kept equal in your experiments; uncontrolled factors can cause false results. (Uncontrolled variables will mess up your experiment.) How is the control group treated differently than the experimental group.? 14. A control group doesn't experience the independent variable. What is an experimental group? 15. An experimental group are subjects that experience the factor that is change in an experiment. What is a “blind” experiment? 16. When the subjects of an experiment or the person collecting results is unaware of whether a given subject is part of the experimental or control group. Why are “blind” conditions done in an experiment? 17. Placebo affect and experimenter bias are controlled by blind conditions in an experiment. What are the characteristics of life? 18. Organization, having cells, responding to stimuli, homeostasis, metabolism, development, and reproduction are the characteristics of living things. Summarizing the organization found in complex multicellular organisms. 19. Biological molecules are combined and organized to make up organelles. Organelles are the parts of the cell. Similar cells make up tissues. Tissues working together make up organs. Organs that work together make up organ systems. Organ systems make up organisms. What is a cell? 20. A cell is the smallest unit of an organism that can perform all life functions. Give an example of a plant responding to a stimuli. 21. Leaves growing towards light or roots growing downward is a plant responding to stimuli. What is homeostasis? 22. Homeostasis is the maintenance of a stable level internal conditions even though environmental conditions are constantly changing. What is metabolism? 23. Metabolism is the sum of all the chemical reactions that take in and transform energy and materials from the environment. What is cell division? 24. Cell division is the formation of two new cells from an existing cell. Contrast how unicellular and multicellular organisms grow. 25. Unicellular organisms grow through cell enlargement, while multicellular organisms grow mainly by increasing the number of their cells through cell division. What is the difference between growth and development? 26. Growth is just getting bigger, whereas development involves cell division and cells changing into different kinds to perform different functions. Contrast asexual and sexual reproduction. 27. The offspring and parent have identical genes in asexual reproduction, whereas the offspring of sexual reproduction gets a mix of genes from two parents. 28. What is a gene? A gene is a short segment of DNA that contains the instructions for a single trait of an organism.
 * 1) 20 Test Review assignment.

9/25 Review and reinforcement for the up coming test.
 * 1) 14 Do Now (6-9)
 * 2) 19 Two Column Definitions Chapter 2 Section 1 on page 31.

9/24
 * 1) 18 pH Acid Base Notes

9/23
 * 1) 15 Water Presentation
 * 2) 17 Definition Chapter 2 Section 3


 * 1) 16 Extra Credit

9/22 1. Energy has the ability to do work.
 * 1) 15 Energy Presentation
 * 2) 15 Energy

2. Energy takes on many forms and be converted between these different forms.

3. Matter has three states.

4. The state of a substance is determined by the motion of it molecules/temperature.

5. Chemical reaction require and give off energy.

6. Metabolism is all of the chemical reaction that occurs in an organism.

7. Activation energy is the amount of energy needed to start a chemical reaction.

8. Catalysts are substances that reduce the activation energy needed for a reaction to occur.

9. An enzyme is a protein or RNA molecule that speeds up a metabolic reaction without being changed or destroyed.

10. Enzymes reduce the activation energy required for a reaction to take place.


 * 1) 14 Do Now (1-5)

9/21 Finish Facts on Drawing.

9/18 __#13 Organelles of a Eukaryotic Cell__: I. Draw a cell with the following organelles or draw each organelle in a section of a grid. __Organelles__: Nucleus Chromosome Nucleolus. Mitochondria Ribosome Rough Endoplasmic Reticulum Smooth Endoplasmic Reticulum Golgi Body Lysosome Vacuoles

Bonus: Centrioles – only in animal cells Cell Wall – only in plant, fungi, and bacterial cells Large vacuole – only in plant cells Chloroplasts – only in plants, algae, and some single cell eukaryotes

II. Title and label your drawing

III. Write the function of each organelle.

Grading: Drawing and labels are visually pleasing – 25% Titles and labels correct – 25% Functions of organelles correct – 50% Bonus – depends on additional material

Alternative Assignment: Draw a picture on a topic in your textbook. Title and label your picture. Add ten facts that explain the picture.

9/17 Warm Up: Do Now Assignment: 2_2 Study Guide

9/16 Finish: Microscope Notes Assignment: 2_1 Study Guide

9/15 Warm Up: #10 Do Now (6-10) Continue: #11 Matter Details Notes Questions, Diagrams, lecture, and notes.

9/14 Warm Up: #10 Do Now (1-5) Start: #11 Matter Details Notes

9/11 Warm Up: Focusing a microscope and which knob to use with the low and higher power objective lenses. Assignment: #9 Composition of Matter Notes 1. Matter is anything that occupies space and has mass. 2. Mass is the quantity of matter in an object. 3. Weight is the force produced by gravity acting on a mass. Would you weigh the same on earth and the moon? Would your mass be the same on earth and the moon? 4. Elements have atoms with the same number of protons. 5.Elements can not be broken down by chemically. 6. Four elements: Oxygen, carbon, hydrogen, and nitrogen make up 90 percent of the mass in living things 7. Atoms have a nucleus containing protons and neutrons. 8. Protons have a positive charge. Neutrons have no charge. The nucleus of an atom is surrounded by the same number of electrons as it has protons. Electrons move around the nucleus at nearly the speed of light, have little mass and are negatively charged. Electrons surround the nucleus in energy levels. 13. Atoms have a no charge due to having an equal number of protons and electrons. Compounds are made up of two or more elements in fixed proportions. H2O Atoms are chemically stable when their highest energy level of electrons is full. Most atoms are not stable so they bond in certain combinations to become more stable to totally fill their outer energy levels. 17. The first energy level holds two electrons and the second holds eight. Chemical bonds are the attractive forces that hold atoms together. A covalent bond forms when two atoms share one or more pairs of electrons. 20. The outer energy level of oxygen atoms is two electrons short of being full and hydrogen atoms are short one. This is why one oxygen atom bonds with two hydrogen atoms to form the compound water. 21. An atom is the smallest piece of an element that retains the properties of that element. 22. A molecule is the smallest piece of a compound that retains the properties of that compound. 23. Ionic bonds form when an electron is transferred from one atom to another. 24. Ionic bonds are due to the opposite charges between the atoms due to the transferred electrons. 25. The formation of ionic bonds occurs when the transfer of electrons makes it so the outer electron level of each atom is full. 26. Na (sodium) has one electron in its outer level and Cl (Chlorine) has seven, so the transfer of the electron from the Na to the CL leaves both with a full outer electron level.

9/10 Warm Up: Have student read a short description of a hypothetical experiment. Assignment: #8 Microscope Notes.

9/9 Warm Up: Draw Concept Map of Scientific Method Finish: #7 Scientific Method Sponge Bob Experiments

9/8 Warm Up: #6 First 5/Last 5 (13-17) Start: #7 Scientific Method Sponge Bob Experiments

9/4 Warm Up: #6 First 5/Last 5 (9-12)
 * 1) 5 Bio Themes -Topics and Details

9/3 Warm Up: #6 First 5/Last 5 (5-8)
 * 1) 5 Bio Themes -Topics and Details

9/2 Warm Up: #6 First 5/Last 5 (1-4)
 * 1) 5 Bio Themes -Topics and Details

9/1 Finish: #4 Tack Toss Start #5 Bio Themes -Topics and Details

8/31 Start: #4 Tack Toss Activity – Hypothesis, Experiment, Gather data, Analyze data, and Conclusion. Finish: #3 Concept Map

8/31/09 Warm up: Review the six characteristics of life and six levels of organization with students using their concept maps. Finish Assignment #3: Make a concept map of the notes for Ch.1_1 using assignment #2. #3 TACK TOSS ACTIVITY (Click link to see the activity) 8/28/09 Warm up: Review the six characteristics of life and six levels of organization with students using their notes. Assignment #3: Make a concept map of the notes for Ch.1_1 using assignment #2. Instuct students on how to put the concepts from their notes into a concept map.

8/27/09 Warm up: Reinforce the terms and concepts presented yesterday. Finish assignment #2 from yesterday. Finish presentation on concepts and vocabulary of chapter 1_1. (Required notes listed 8/26)

(Copy the following in Cornell note style. Notes in one column and questions in the other.)
 * 1) 2....Characteristics of Life

Characteristics of Life: Organization and cells Respond to Stimuli Homeostasis Metabolism Growth and Development Reproduction

Levels of Organization: Organ systems Organs Tissues Cells Organelles Biological molecules


 * Biological molecules** are compounds that provide the physical structure and carry out cellular functions like movement and energy use or storage.

are tiny structures in cells that carry out all the functions necessary for the cell to stay alive.
 * Organelles:**

All living organisms are made up of cells. A cell is the smallest unit that can perform all of life's processes. unicellular organisms – one cell that does all of life's processes. multicellular organisms – many cells where different cells do different life processes. Cells are surrounded by a membrane, contain cytoplasm and DNA.
 * Cells:**

are groups of similar cells that allow an organ to function.
 * Tissues**

Organs are structures that carry out specialized jobs within an organ system. Organs are structures made of one or more tissues that work together to perform a function.
 * Organs**:

Organisms with a high level of organization have organ systems. An organ system is a group of organs that work together to provide a function.
 * Organ Systems**


 * Organism**

__**Respond to Stimuli**__: Organisms must respond to physical or chemical changes in their internal or external environment.

is the maintenance of a stable level of internal conditions even though environmental conditions are constantly changing.
 * Homeostasis**

is the sum of all the chemical reactions that take in and transform energy and material from the environment.
 * Metabolism**

Occurs through cell division- growth, repair, and reproduction
 * Growth and Development**

Reproduction: Asexual Sexual

8/26/09 Warm up: Quickly reinforce classroom rules and the need to make an effort to learn. Presentation with a few visual motivational items. Finish assignment #1 from yesterday. Start presentation on concepts and vocabulary of chapter 1 section 1. (Required notes below) Assignment #2....Characteristics of Life [Cornell Style Notes ]

8/25/09 Warm up: Presentation on effort, learning, academic background knowledge, status and income. __Assignment #1__...... Scientific Method

[Read the story and answer the questions. Also copy the definitions given.]

Steps of the Scientific Method: •State the problem •Gathering Information •Form a hypothesis •Test the Hypothesis with an Experiment •Collecting and Analyzing the Data •Drawing Conclusion

[Apply each step in the scientific method to the story below.]

State the problem: [A pet owner had his four cats boarded while he travels. The cats seemed healthy when they arrived, but a technician notices that two of the cats start scratching and chewing at their skin. After three days, these same two cats have bare patches of skin with red sores.] 1. What is the problem?

Gathering Information: [The technician knows that cat's sometimes change their behavior when moved to a new place, so she watches all four cats for two days. Other than the scratching and chewing by the cats with sores, the behavior of all four cats seems the same. The technician called the owner and found out that he fed the cats the same food as she did. While observing the cats, the technician also noticed that the cats scratched most after using the litter box. She called the owner and asked what brand of litter he put in the cat's litter box. The owner used a different brand than she did, so she compared the ingredients of the two kinds of litter. The difference was that the owners litter was deodorant free, while the brand she used had a deodorant.] 2. What three pieces of information were gathered?

Form a hypothesis: [Based on the information gathered, the next thing the technician does is form a hypothesis.] •A hypothesis is an explanation that can be tested. (Copy this definition) 3. What hypothesis should the technician form?

Test the Hypothesis with an Experiment: [The technician gets the cats owners permission to test her hypothesis.] 4. How how you would test the hypothesis?

Controls •A control is the standard to which the outcome of a test is compared. (Copy this definition) 5. What “control” could you include in this testing of the hypothesis?

Variables •A variable is something in an experiment that can change. (Copy this definition) 6. What is the variable in this test?

Collecting and Analyzing the Data: [The technician observes the cats for one week. During this time she collects data.] 7. What data should be collected in this test?

Drawing Conclusions: [The data shows that the control cat scratches and chews more often than the experimental cat does. The sores on the skin of the experimental cat begin to heal, but those on the control cat do not.] 8. What conclusion can be drawn from this data?

[Further testing to be more sure of that the conclusion is correct:]

9. How could the control cat be used to support the conclusion?

10. How could the experimental cat be used to verify the conclusion?

11. Would both of these latter tests be ethical on someone's pet?

(Adapted from a story in Glencoe's Life Science textbook.)