SI131 Ch 2 FA24 Kerr Classmarker Test PDF

SI131 Ch 2 FA24 9/11/24, 11:48 PM Kerr Classmarker Test SI131 Ch 2 FA24 Alannah Acfalle Points: 51 / 51...

SI131 Ch 2 FA24 9/11/24, 11:48 PM Kerr Classmarker Test SI131 Ch 2 FA24 Alannah Acfalle Points: 51 / 51 Percentage: 100% Duration: 00:37:50 Date started: Wed 11 Sep '24 23:01 Date finished: Wed 11 Sep '24 23:39 Feedback You passed the test with a 60% or better. If you did not make 100%, you have one more chance to improve your grade. all questions 27 correct 0 incorrect 0 bookmarked https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 1 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 1 of 27 Points 1/1 The four elements that make up about 96% of body weight are ________. A. carbon, oxygen, phosphorus, calcium B. nitrogen, hydrogen, calcium, sodium C. carbon, oxygen, hydrogen, nitrogen D. sodium, potassium, hydrogen, oxygen Feedback Correct https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 2 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 2 of 27 Points 1/1 The most abundant element in the human body is A. hydrogen B. carbon C. nitrogen D. oxygen Feedback Correct. Make you that you understand the definitions of atoms, molecules, and compounds. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 3 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 3 of 27 Points 1/1 The most abundant chemical compound in the human body is A. water (H20) B. carbon C. oxygen D. Glucose (C6H1206) Feedback Correct. A compound is a molecule with 2 or more different elements. H2O is the most common compound in the body. Oxygen is the most common ELEMENT in the human body, while carbon is the second most common element. Question 4 of 27 Points 1/1 The subatomic particles most responsible for chemical reactions are A. protons B. neutrons C. quarks https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 4 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM D. electrons Feedback Correct. Valence electrons in the outermost shell of an atom are farthest from the positively charged nucleus, and thus are more available to make bonds with other atoms by being: equally shared in a nonpolar covalent bond, OR, unequally shared in a polar covalent bond, OR, completely transferred in an ionic bond Examples: 1. Nonpolar Covalent bond - 2 oxygen atoms share their valence electrons - each atom has 2 electrons to share that allows them to each have 8 electrons in their outer shells, giving both stable octets. This image only shows valence electrons. 2. Polar covalent bond - in a water molecule, valence electrons are unequally shared because oxygen pulls most of the negative charge from each hydrogen atom. This makes water a polar molecule. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 5 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM 3. Ionic Bond - in a salt molecule, like NaCl, sodium transfers 1 electron to chlorine to https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 6 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM make it a chloride ion. This transfer makes a positive sodium ion, Na+, and a negative chloride ion, Cl-. The opposite charges cause them to bond together to make solid NaCl. Question 5 of 27 Points 7/7 Below are descriptions relating to atoms. Match the description to the correct term. The smallest particle of an element that Atom retains the chemical and physical properties of that element. This subatomic particle is neither positively Neutron nor negatively charged and is located in the nucleus of an atom. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 7 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM When a neutral atom loses one or more Cation electrons, this positively-charged ion is formed. When atoms of the SAME element are Molecule of an element bonded together, a __________________________ is formed. When two or more atoms of DIFFERENT Compound elements are bonded together, a ______________ is formed. When a neutral atom GAINS one or more Anion electrons, this negatively-charged ion is formed. This positively-charged subatomic particle is Proton located in the nucleus of an atom. Question 6 of 27 Points 1/1 When atoms bond to each other, they gain stability by sharing or gaining electrons to have a stable octet (8 electrons), or a stable duet (2 electrons). True False Feedback https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 8 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Correct For example, in NaCl (sodium chloride), Na gives away its 1 valence electron to Cl. Na+ is stable because 8 electrons, that were in the 2nd highest shell, are now in the outermost shell. Cl- is stable because it added 1 more electron to the 7 valence electrons that were in its outermost shell. Hydrogen and Helium are the only 2 elements that form stable duets. Helium already has a stable duet because its one energy level (or orbital) is filled with 2 electrons and cannot accommodate more. Hydrogen only has one energy level (or orbital), which can only hold a maximum of 2 electrons. Since hydrogen only has 1 electron, it needs to share 1 more electron to attain a stable duet. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 9 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 7 of 27 Points 11 / 11 Topic: Elements, atoms, molecules, compounds. Match the descriptions with the correct term or phrase: A ___________represents an element with 1 Chemical symbol or 2 letters. The ___________ is the number of protons Atomic number and number of electrons (in a neutral atom). This is the combined number of protons and Mass number neutrons in an atom. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 10 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM The mass of an ATOM is expressed in atomic mass units or amu _________ of an element have the same isotopes number of protons, but differ in the number of neutrons. __________, such as tritium or uranium, radioisotopes decay into more stable atoms by releasing radioactive particles. Oxygen gas, O2, is an example of a molecule ____________ of an element. Carbon dioxide, CO2, is an example of a compound ______________. In a ______________ bond, electrons are polar covalent unequally shared. In an __________ bond, electrons are ionic transferred from a metal to a non-metal element. In a _________ bond, electrons are shared covalent equally. Question 8 of 27 Points 1/1 https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 11 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM The type of bond formed between water molecules is a ______________bond. These bonds form between the partially-positive hydrogen atoms of one water molecule, and the partially __________ oxygen atom of another water molecule. A. hydrogen;negative B. covalent;positive C. polar;negative D. ionic;negative Feedback Correct https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 12 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 13 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 9 of 27 Points 1/1 What does the chemical formula for glucose, C 6H12O6 , tell us? A. There are 6 calcium, 12 hydrogen, and 6 oxygen atoms. B. There are, 6 carbon, 12 hydrogen, and 6 oxygen atoms. C. The molecular weight is 24. D. The substance is a colloid. Feedback Correct. The subscripts indicate the number of atoms of the preceding element. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 14 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 10 of 27 Points 5/5 Topic: Forms of Energy. Match the descriptions to the correct energy term. Legs moving the pedals of a bicycle are an Kinetic energy example of energy in motion. When the phosphate bonds of ATP are Chemical energy broken, this type of energy is released to do cellular work. Energy that travels in waves or particles, like Radiant energy ultraviolet rays and x-rays, light, and heat. Energy that is produced by the flow of Electrical energy charged particles along a conductor, or the flow of ions across a membrane. Energy that is stored and would be released, Potential energy like ATP in muscle cells. Feedback Correct Question 11 of 27 Points 5/5 Match the descriptions of mixtures and solutions to the correct terms. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 15 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM In this type of heterogeneous mixture, the Colloid particles do not settle. In this type of heterogeneous mixture, the Suspension particles will eventually settle. This type of homogeneous mixture appears Solution clear and does not have particles that scatter light. This type of homogeneous mixture will not Solution settle. Blood is a type of heterogeneous mixture Suspension called a _______ Feedback Correct. Both suspensions and colloids are heterogeneous because components of the mixtures are not completely dissolved and can be seen. Suspensions can be separated when the particles settle to the bottom, but colloidal particles are charged, which keeps them from settling. Solutions are homogeneous or clear because the solute is completely dissolved in the solvent. Light passes through solutions, rather than scattering, because they are clear and you can see through them. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 16 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 12 of 27 Points 1/1 Which properties of water are help us to cool off when we sweat? A. high heat of vaporization and polar solvent B. high heat capacity and high heat of vaporization C. reactive nature of water and polar solvent D. reactive nature of water and high heat capacity E. cushioning Feedback Correct The high heat capacity of water allows liquid water to absorb and store a lot of heat. The high heat of vaporization of water allows it to change from a liquid into a gas at a high temperature. When water vaporizes, a lot of heat is released from breaking the hydrogen bonds between the water molecules. When our body temperature rises, water molecules absorb the heat energy and are released as sweat droplets. The sweat evaporates as it reaches the surface of the skin, thus drawing the heat out of our bodies and cooling it down. https://www.youtube.com/watch?v=mbAC6HpTu34 Question 13 of 27 Points 1/1 https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 17 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM The general structure of an amino acid is shown below. Note that the amino group, NH 2, has a nitrogen atom. Animals, including humans, depend on amino acids to provide nitrogen to the body. Amino acids are the building blocks of larger molecules called __________________. The R represents a specific group that identifies a particular amino acid. The carboxyl group, - COOH, is the acid part of the compound. A. carbohydrates or polysaccharides B. lipids C. proteins or polypeptides D. glycogen https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 18 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Feedback Correct Question 14 of 27 Points 1/1 Choose the correct statement about the pH of a substance. A. The lower the pH value, the greater the hydrogen ion, H +, concentration. B. The higher the pH value, the higher the hydrogen ion, H +, concentration C. pH values below 7 are alkaline or basic. D. The higher the pH value, the lower the hydroxide ion, OH -, concentration https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 19 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Feedback Correct. pH refers to the concentration of hydrogen ions [H+] in a substance. the higher the concentration of hydrogen ions, the more acidic a substance is. the higher the concentration of OH- ions, the more alkaline or basic a substance is. The pH scale runs from 0-14. pH 7 is neutral; below 7 is acidic; above 7 is basic or alkaline. at pH 7, the concentration of H+ ions = the concentration of OH- ions https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 20 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 15 of 27 Points 1/1 In the body, which of the following processes require energy in the form of ATP? A. chemical work B. mechanical work C. transporting substances across a cell membrane D. All of the above require energy to occur. Feedback Correct. Note: Processes that require energy are "active", whereas processes that do not require energy are "passive." An example of a passive process is diffusion. Diffusion occurs when a substance moves from an area where it is high in concentration to an area where it is low in concentration. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 21 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 16 of 27 Points 1/1 Which of the following statements is FALSE regarding the rate of chemical reactions? A. Chemical reactions usually proceed more quickly at higher temperatures. B. Larger particles move faster than smaller ones and thus collide more frequently and more forcefully. C. Biological enzymes (catalysts), increase the rate of chemical reactions, sometimes while undergoing reversible changes in shape. D. Chemical reactions have a faster rate when reactants are present in higher concentrations. Feedback Correct. Question 17 of 27 Points 1/1 A polymer, such as a polysaccharide or polypeptide, forms when "building block" molecules, like glucose or amino acids, are joined together by a type of reaction called ________________________________. A. hydrolysis B. addition of carbon atoms C. dehydration synthesis D. removal of carbon atoms https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 22 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Feedback Correct. Dehydration synthesis involves removing a water molecule to form a chemical bond. Hydrolysis involves adding a water molecule to break a chemical bond. Below is a diagram showing the removal of water, dehydration synthesis, to connect two molecules of glucose to make a longer sugar chain: Below is a diagram showing the removal of water, dehydration synthesis, to connect two amino acids to make a longer protein chain: Question 18 of 27 Points 1/1 Which protein structural level occurs when a long chain polypeptide forms a coil or alpha helix? https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 23 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM A. primary structure B. secondary structure C. tertiary structure D. quaternary structure Feedback Correct. Primary structure would be a single linear or straight protein polypeptide chain. Secondary structure involves coiling or folding of a polypeptide chain using hydrogen bonds. This produces a coiled alpha-helix or a beta-pleated sheet. Tertiary structure has a more 3-dimensional structure with more folding due to interactions of the R-groups. Quaternary structure involves bonding tertiary proteins together to make an even larger protein molecule, e.g., hemoglobin. Question 19 of 27 Points 1/1 https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 24 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Which statement about enzymes is FALSE? A. Enzymes require contact with substrate in order to assume their active form. B. Most enzymes can catalyze millions of reactions per minute. C. Enzymes may use coenzymes derived from vitamins or cofactors from metallic elements. D. Enzymes may be damaged by high temperature. E. Enzymes lower the activation energy of a reaction allowing it to proceed more quickly than it would have without the enzyme. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 25 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Feedback Correct. Enzymes, or biological catalysts, DO NOT have to be attached to their specific substrate compound to be in their active form. Enzymes lower the activation energy of a reaction allowing it to proceed more quickly than it would have without the enzyme. Biological catalysts do not change chemically in a reaction, but their physical structure can change slightly to bind to a substrate, and reverts when products are released. Enzymes may be damaged by high temperature. Enzymes may use coenzymes derived from vitamins or cofactors from metallic elements. Most enzymes can catalyze millions of reactions per minute. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 26 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 20 of 27 Points 1/1 ___________ is fat soluble, produced in the skin on exposure to UV radiation, and necessary for normal bone growth and function. A. Vitamin K B. Cortisol C. Vitamin A D. Vitamin D Feedback Correct Vitamin D is made in the skin by a reaction between cholesterol and ultraviolet rays from the sun. Both Vitamin D and cholesterol are soluble in fat and, therefore, can be stored in adipose (fat) tissue in the body. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 27 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 21 of 27 Points 1/1 The energy needed to make ATP comes from the breakdown or catabolism of_____________ during the reaction known as aerobic respiration. A. carbon dioxide B. water C. a protein D. glucose Feedback Correct In aerobic respiration, glucose reacts with oxygen gas and is catabolized (broken down): nutrients Glucose + Oxygen ----------> carbon dioxide + water + ATP + heat https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 28 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 22 of 27 Points 1/1 When glucose monomers are joined to form glycogen, this is an example of a process called ________. A. oxidation B. anabolism C. catabolism D. an acid-base reaction E. an enzyme reaction Feedback Correct. Building larger compounds from smaller units is an anabolic process or anabolism. Breaking down large compounds into their units or basic elements is catabolism. Dehydration synthesis is the reaction that allows anabolism to occur. Hydrolysis is the reaction that results in catabolism. For example, glycogen gets hydrolyzed into glucose monomers. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 29 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 23 of 27 Points 1/1 Buffers resist abrupt and large changes in the pH of body fluids by releasing or binding ions. True False Feedback Correct Buffer example: The normal pH range for blood is 7.35-7.45. If the pH of blood drops below 7.35, it is more acidic and the concentration of hydrogen ions (H+) is too high. To correct this, the excess H+ must be removed by binding them to bicarbonate ions, HCO3-. This means that the reaction will move to the left. Carbonic acid Hydrogen ion + bicarbonate ion H2CO3 H+ + HCO3- Question 24 of 27 Points 1/1 https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 30 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM A patient is hyperventilating. This means that they are releasing too much carbon dioxide from the blood. Hyperventilation causes the pH to increase above 7.45. Recall that when carbon dioxide dissolves in the blood, it produces carbonic acid. How can the carbonic acid-bicarbonate buffer system work to correct this imbalance? That is, in which direction will the reaction proceed to restore the blood to the normal pH range of 7.35 - 7.45? Carbonic acid ↔ Hydrogen ion + bicarbonate ion H2CO3 ↔ H+ + HCO3- A. The reaction proceeds to the left: Carbonic acid, H2CO3, dissociates to form more H+ and raise the pH B. The reaction proceeds to the right: HCO3- binds with H+ to form H2CO3 and raise the pH C. The reaction proceeds to the right: H2CO3 dissociates to form more H+ which lowers the pH D. The reaction will proceed to the left: H+ binds to HCO3- to form H2CO3 to raise the pH Feedback Correct. To maintain homeostasis, the pH of blood has to be kept between 7.35–7.45. Hyperventilating and blowing off too much carbon dioxide can cause the blood pH to increase above 7.45, which is alkaline. To fix this, the buffer system must produce more hydrogen ions to lower the pH and make the blood more acidic and return it to the normal pH range. The reaction must proceed to the right: H2CO3 dissociates into H+ and HCO3– so that more H+ ions will be available to lower the pH to the normal range. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 31 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 25 of 27 Points 1/1 Choose the correct statement about phospholipid molecules. A. They have a polar, hydrophilic phosphate 'head' that is bonded to 2 nonpolar, hydrophobic 'tails'. B. water molecules are repelled by the 'heads' C. water molecules are attracted by the 'tails' D. Phospholipid molecules only form one layer in a plasma cell membrane. Feedback Correct. Water molecules are attracted to the hydrophilic head of a phospholipid and repelled by the hydrophobic tails. An animal cell membrane consists of 2 layers of phospholipids in which the tails of both layers face each other, the heads of the outer layer face outward, and the heads of the inner layer face the inside of the cell. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 32 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 33 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 34 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 26 of 27 Points 1/1 All of the following are lipids except ____________. A. steroids B. eicosaniods C. cholesterol D. polypeptides Feedback Correct. A polypeptide is a linear protein molecule made up of amino acids. https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 35 of 36 SI131 Ch 2 FA24 9/11/24, 11:48 PM Question 27 of 27 Points 1/1 Match the options below to either DNA or RNA. The sugar is ribose. RNA The structure is a double helix (coil). DNA Contains the nucleotide bases adenine, DNA thymine, guanine, and cytosine. Contains the nucleotide bases adenine, RNA uracil, guanine, and cytosine. The structure is linear. RNA The sugar is deoxyribose. DNA https://www.classmarker.com/online-test/start/results/?quiz=6dp66d3c2e3f1947 Page 36 of 36