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Chapter 1-3 The pH of your small intestines is around 7.5 and the pH of your large intestine can be 5.5. As substances travel from the small intestines to the large intestine, what would happen to the H+ ion concentration? - it increases 100 fold The negative logarithm of the hydrogen ion concentration in the solution is referred to as: PH Sue was monitoring the oil spill into the Gulf of Mexico from an oil tanker. From her observations, she noted that the oil was moving as large patches in the water. It did not appear as though the oil was dissolving into the water. Why did the oil not dissolve into the water? Hydrophobic interactions The high heat of vaporization of water helps you to feel cooler when you sweat because the transition of water from a liquid to a gas requires a ______ of energy to break hydrogen bonds. The energy is _____ from heat produced by your body, thus helping to lower the surface temperature of your body. Input; obtained @Proteins are three dimensional molecules made of strands of amino acids (imagine a ball of string). There are 20 different amino acids used in proteins found in living organisms. Some of these amino acids are polar and others are nonpolar. Where would a series of nonpolar amino acids most likely be located in a protein that is found in the cytosol of an animal cell? In the interior of the protein According to most car mechanics, plain water is the best coolant to use in an engine provided the engine is not being exposed to freezing temperatures. If the car is subject to freezing temperatures then a mixture of water and ethylene glycol (antifreeze) is recommended but it does not cool as efficiently as plain water. Why would ethylene glycol reduce the cooling efficiency of water? Ethylene glycol has a lower heat capacity than water. How many hydrogen bonds can a water molecule form? 4 @Plants transport water to their leaves through the xylem when water evaporates from the leaves. The evaporating water pulls other water molecules up the xylem through ____ . Hydrogen Bonds Life is thought to have evolved from complex molecules formed by the interaction of smaller molecules in oceans and the atmosphere. The substance which brought these molecules together to interact is water Carbon has 4 valence electrons and oxygen has 6. Carbon dioxide would contain _____. two double covalent bonds How is the bond in F2 different from the bond in KCl? F2 is covalent and KCl is ionic When atoms gain or lose electrons, they become negatively or positively charged. These negatively or positively charged atoms are known as ions Atoms containing a specific number of protons are called: elements @In a chemical analysis of an animal tissue sample, which element would be in the least quantity? Iodine

All atoms possess the ability to do work. The term that is defined as the ability to do work is: energy @Oxygen-16 is abundant and has 8 protons and 8 neutrons. Oxygen-18 has two extra neutrons. These two forms are: oxygen isotopes The sub-atomic particle with a positive charge is _____. A proton @Regardless of its shape, a given orbital may contain no more than 2 electrons All atoms tend to fill their outer energy levels with the maximum number of electrons, usually eight. Depending on whether atoms satisfy the octet rule will predict: the chemical behavior of the atoms The smallest subatomic particle is the ______. Electron The half-life of Carbon-14 is approximately 5,700 years. Using this information scientists have been able to determine the age of some artifacts left by humans. A scientist wants to know approximately how old a piece of wood was that she found on the floor in an old cave that had recently been discovered. She removed the wood (with permission) to her laboratory. Her wood sample contained 2 grams of Carbon-14. If the age of the wood was determined to be 22,800 years old, how much Carbon-14 originally existed in this piece of wood? 32 grams A candy bar contains 108 calories per serving. There are 4 grams of carbohydrate, 5 grams of protein, and 8 grams of fat in a serving. How many of the calories come from fat? Note: One food calorie equals one kilocalorie. 72 @Sudan IV, a dye that binds to nonpolar molecules, is used to detect the presence of macromolecules in food. Sudan IV would test positive in the presence of what macromolecule? Fats @Biological membranes contain bilayers containing mostly ______. Phospholipids

Common lipids for energy storage are: triglycerides @The myoglobin protein, which carries oxygen in muscle cells, has only the first three levels of protein structure. What can you infer about myoglobin? Myoglobin is made of only one polypeptide chain What characteristic would the R groups of amino acids have if they are located within the interior of biological membranes? The R groups would hydrophobic. @You arrive late to a biological seminar. However, just as you enter the room, you hear the speaker referring to the "amino end" and the "carboxyl end" of a macromolecule. Immediately, you know that they are talking about a: protein Hemoglobin transports oxygen in the blood and consists of a chain of 146 amino acids. How many different types of amino acids are used to construct proteins? 20 @Which amino acid is least soluble in water? Isoleucine

@What type of monomer does ATP represent? Nucleotide @The nitrogenous base that is only found in DNA and not in RNA is: thymine The information storage molecules of cells are called: nucleic acids @DNA and RNA contain functional units known as:nucleotides @The nitrogenous base that is only found in RNA and not DNA is uracil !!Benedict's reagent is a chemical that is used as a test for the presence of a free aldehyde functional group on glucose. The aldehyde is used when glucose and fructose bind together to form sucrose, and the Benedict's test is negative. Starch contains a great deal of glucose but gives a negative Benedict's test because: only the glucose at the end of a chain of starch will have an exposed aldehyde functional group to react with Benedict's reagent. A bobcat is feeding on a white-tailed deer. It first eats the liver, which is rich in stored sugars. In what form would sugar be stored in the deer’s liver? Glycogen Carbohydrates are polymers formed of structural units called:monosaccharides. A polysaccharide that is composed of modified glucose subunits and that is found in the exoskeletons of insects and crustaceans is known as: chitin You label cells with a radioactive isotope of sulfur (35S). The only molecules that would be radioactively labeled in these cells are: proteins Organic molecules have a carbon backbone and _____ such as -OH and -NH2 that affect their chemical properties. Functinal groups At the pH of most bodily fluids, which functional group will lose a proton and which functional group will accept a proton? Carboxyl;amino @Fructose and galactose both have six carbon atoms, twelve hydrogen atoms and six oxygen atoms, just like glucose. A friend of yours says: "Since those sugars have the same number of atoms, they should have the same name." You answer: "While they do have the same number and type of atoms, they are named differently because they are alternate forms of the monosaccharide, glucose." Dr. Edward Jenner realized that cows have a disease called cowpox, which is like a disease that infects humans called smallpox; Jenner noticed that milkmaids whose hands were infected with cowpox were not contracting smallpox. Jenner infected a child with the pus from a cowpox blister, and found that the child did not contract smallpox. Which statement represents a supporting hypothesis? The cowpox infection will prevent the child from being infected by the smallpox virus. A student poses the question: How does the presence of dissolved salt affect the freezing point of water? To answer this question, the student set up two conditions. In the first condition, the student added salt to water in a container and referred to this condition as

the variable. In the second condition, the student did not add any salt to water in a second container and referred to this condition as the control. The student took both containers and attempted to freeze the water at various temperatures to assess the freezing point. Would this be a valid experiment? Yes, because there is one variable and a control Dr. Ratard was trying to determine the cause of a mysterious epidemic affecting fish in the gulf of New Mexico. His proposal that the deaths were caused by an organism called a protist is considered a(n) _________ hypothesis Gingko trees are known to lose their leaves at a certain time each year throughout the United States. Based on this information, Gingko trees in China must behave the same way. These statements are an example of: deductive reasoning Differences in domesticated animals over relatively short periods of time most likely occur through artificial selection Recent discoveries of microscopic fossils have extended the known history of life to about: 3.5 billion years ago. Cell theory is one of the foundations of biology. What are the tenets of the cell theory? Check all that apply. -All organisms are made up of more than one cell. -All cells have the ability to move. -Cells carry genetic material passed to daughter cells during cellular division. -Cells arise from other cells through the process of cell division. -Organisms are formed through spontaneous generation -All living organisms consist of cells

Chapter 4-5 The major histocompatibility complex is important in a T-cell's ability to: recognize self from nonself Cilia and flagella of eukaryotic cells are composed of: microtubules in a 9 + 2 arrangement. When a vesicle moves along microtubules toward the center of the cell, the molecular motor(s) _____ are used? Dynein The distinctive feature of chloroplasts is that they contain a green pigment called: chlorophyll If a water molecule passes through the outer membrane of a chloroplast, how many more membranes will it have to move through to be in the stroma? 1

Based on the function of mitochondria, what substance is able to pass through the outer membrane of the mitochondria easily? Oxygen As ATP moves from the matrix of the mitochondrion to the cytoplasm of a cell, how many membranes will it pass? 2 What is the difference between mitochondria and chloroplasts? Mitochondria are oxidative metabolic bacteria derivatives and chloroplasts are photosynthetic bacteria derivatives. Scientists believe that stimulating growth of algae and other organisms can reduce carbon dioxide amounts in the atmosphere. Where is carbon dioxide consumed in a plant cell? Stroma in chloroplasts Mitochondrial disorders can be caused by mutations in all the following except: cytoplasmic DNA Mitochondria and chloroplasts are the other organelles besides the nucleus that contain: DNA The evolutionary process that created chloroplasts and mitochondria is: endosymbiosis. The organelle involved in the oxygen-requiring process by which the energy harvested from macromolecules is used to generate ATP is the: mitochondria. Nuclear pores permit the passage of all the following except: DNA molecules only outward. Ribosomes are made up of: protein and RNA A distinctive feature of eukaryotes is the organization of tightly packaged chromosomal DNA with proteins into a membrane-bound structure called a: nucleus. During which cellular process do all three forms of RNA associate? protein synthesis Prokaryotic cell movement is attributed to: flagella The peptidoglycan of bacterial cell walls contains a carbohydrate matrix linked together by short chains of: amino acids A circular molecule of DNA devoid of any histone proteins describes the chromosome of a (an): bacteria A team of researchers is studying the external structures on the dorsal (back) surface of a spider mite. The spider mite seems to be the habitat of an even smaller mite, which is approximately 0.05mm. While they can see the dorsal surface of the spider mite with their naked eye, they cannot see the mite clearly. The researchers are writing a grant to provide support for a microscope to use to study these new mites. They need to purchase a microscope with a high magnification to observe the new mites on their habitat. Based on the information given, what type of microscope would you suggest?

binocular compound light microscope If you were to use antibodies that were chemically bonded to a stain in order to visualize the expression pattern of a protein in a fixed tissue, what experimental techniques and equipment would be applicable? immunohistochemistry, bright-field microscopy The cytoplasmic space in eukaryotic cells is occupied by many diverse membrane-bound structures with specific cellular functions called: organelles Given what is known about the minimal essential functions of cellular life, if you could create an artificial cell, what cellular structures must you include? Ribosomes The semifluid matrix that surrounds organelles in a cell is called the: cytoplasm Incubation of cells at 20°C blocks the release of proteins from the trans-Golgi. Under such conditions, you would expect to see a decrease in exocytosis. Matt is studying how the protein transferrin enters cells. He examines cells that have taken up transferrin, and finds clathrin-coated vesicles. What mechanism was used to take transferrin into the cell? Receptor-mediator endocytosis During neuronal signaling, a change in membrane potential will cause sodium channels to open and let Na+ ions diffuse down their concentration gradient into the cell. Which of the following helps establish the concentration gradient necessary for this process to occur? Na+/K+ pump Membrane proteins serve many functions. One of the functions is transportation of substances across the membrane. If a cell biologist placed cells into an environment in which a chemical has been added that blocks the function of only carrier proteins, the process that will be affected is active transport. Which type of proteins is embedded in the cell membrane in both active transport and facilitated transport? Carrier If Na+ levels were depleted in the extracellular fluid, rate of glucose movement would decrease If ATP production is blocked, decreased transport of material across a membrane occurs. Which type of transport is affected? Choose all that apply. - Osmosis - Diffusion - Facilitated diffusion - Active transport - endocytosis

Osmosis is the diffusion of water across a membrane in response to the concentration of one or more of the ______. Solutes A scientist performs an experiment in which they create an artificial cell with a selectively permeable membrane through which only water can pass. They inject a 5M solution of

glucose into the cell and then place the cell into a beaker containing 10M glucose. What effect do you expect to observe? Water moves out of the cell The rate of diffusion of molecules would be fastest in a cell with an: internal concentration of 50 percent and an external concentration of 12 percent in warm temperatures. In the process of diffusion, molecules move from areas where: their concentration is higher to areas where their concentration is lower until an equilibrium is reached. The movement of substances from regions where their concentration is higher to regions where their concentration is lower is called diffusion Choose all that apply. A concentration gradient is exhibited when -intracellular fluid has 5% solute and extracellular fluid has 0.8% solute concentration. -during rest, muscle and liver cells contain high glycogen concentration and blood contains lower concentrations. Insulin stimulates an increase in number of glucose carrier proteins at a cell membrane’s surface. What effect will insulin have on cell function? Choose all that apply. -An increase in insulin, which will increase the diffusion rate. -ATP amounts needed for this transport will increase. -Low insulin levels will decrease the number of available carrier proteins. -Lack of membrane receptors for insulin will decrease amount of glucose taken in. One day during the summer you and some friends make ice cream using an electric ice cream maker. To get the ice cream to form, a mixture of salt and ice is packed around the ice cream maker. A few days later you notice a yellow circle of dead grass where the ice cream maker had been placed. You hypothesize that some of the salt and ice mixture spilled onto the grass and ___. was hyperosmotic to the grass cells causing the yellow circle of dead grass GABA receptors play an essential role in neurotransmission in the central nervous system. In response to the appropriate signal, these receptors open up and allow Cl- to flow into the cell. Given this information, GABA receptors can be classified as a gated ion channel. Protein X contains four transmembrane domains, a short N-terminus and a long C-terminus. Following protein synthesis, the N-terminus of the protein faces the lumen (the inside) of the ER. After protein X is transported to the cell surface via exocytosis, you would expect the N-terminus of protein X to be extracellular. The cell's plasma membrane mediates which of the following transactions with the environment? Choose all that apply. -Ingesting food molecules and sometimes entire cells -Returning waste and other molecules back to the environment -Directing synthesis of various food-digesting proteins -Passing messages to other cells A phospholipid molecule has a polar and a nonpolar end. Because of this, water molecules form hydrogen bonds with the polar end of the phospholipid molecule. Cholesterol functions in the plasma membrane to: maintain fluidity.

The fluid nature of the membranes is attributed to a lateral movement of: phospholipid molecules. How are the tails and heads of membrane phospholipids oriented in their environment?The hydrophobic tails are oriented toward each other and the hydrophillic heads are oriented toward the extracellular fluid and the intracellular fluid. On the outer surface of the plasma membrane there are marker molecules that identify the cell type. Often these molecules are: carbohydrate chains. The lipid layer that forms the foundation of cell membranes is primarily composed of molecules called __________. Phospholipids

Chapter 6-7 When an atom or molecule gains one or more electrons, it is said to be: reduced In an experiment described in a chemistry lab book, the directions state that after mixing two chemicals (A and B) and waiting 5 minutes that A will be oxidized. This means that:chemical A has lost electrons to chemical B. Glucose is converted into glucose 6-phosphate by hexokinase. Glucose 6phosphate then serves as the substrate for the enzyme phosphoglucose isomerase, which converts this reactant into fructose 6-phosphate. Fructose 6phosphate serves as the substrate for phosphofructokinase, which converts fructose 6-phosphate into fructose 1,6-bisphosphate. Based on the information provided, this is an example of what? A metabolic pathway Enzyme 1 converts substrate A into product B. Is this an example of a metabolic pathway? No. This only describes one chemical reaction. A metabolic

pathway includes multiple chemical reactions. Glycolysis is a metabolic process that is conducted by nearly all cells. However, in addition to glycolysis, some cells also make use of another metabolic process called the Krebs cycle. What does this tell you about the evolution of these processes? As a metabolic process, glycolysis likely evolved prior to the Krebs cycle A ribozyme catalyzes a reaction on itself and actually changes shape. This is an example of. intramolecular catalysis. A molecule that closely resembles the shape of a substrate for an enzyme and that decreases the activity of the enzyme would most likely serve as a(n): competitive inhibitor. A current problem in modern medicine is the development of drug resistance mutations. This occurs when a mutation arises in a disease-causing microbe making it resistant to a drug and thus rendering the drug useless in treating a specific disease. Many useful drugs are competitive inhibitors of specific enzymes, and the drug-resistance mutations prevent the binding of the drug. These types of mutations, in addition to preventing compe...