Biology A Unit 1: Lessons 1-5 Questions and Answers Already Passed

Biology A Unit 1: Lessons 1-5 Questions and Answers Already Passed Lesson 1: Lesson 1: Which of the following statements describes a proton of an atom? has a positive charge and is located in the nucleus Study the model. This model shows an atom with two neutrons, one proton, and one electron. Which option shows the correct electrical charges? 2 blank red circles 1 yellow circle with P+ 1 blue circle with E- How is a carbon atom represented? Circle with a "C" on it This element is an essential atom in the structure of proteins. Without this element, the body would be unable to make the proteins it needs to function properly. What element is this? nitrogen What element has the symbol N? nitrogen What is an atom? the smallest unit of matter that has the chemical properties of an element What is a neutron? a neutral particle that is in the nucleus of an atom Which describes electrons? Electrons move at very fast speeds around the nucleus of an atom. Study the image What does this model represent? an oxygen atom What are some functions of calcium? Select all that apply. helping with muscle function making teeth strong What is the symbol for the element potassium? K How is a hydrogen atom represented? Circle with an "H" in it Study the atomic model. What is the correct labeling for the atom? A—nucleus, B—proton, C—neutron D—electron This element can form a wide variety of substances, including long chains. The different substances it forms are central to the molecules found in living things. What element is this? carbon Lesson 2: Lesson 2: The chemical formula for calcium carbonate is CaCO3. How many different elements does a molecule of calcium carbonate have? three Water molecules have two atoms attached to a third central atom, forming an angle. Which ball-and-stick model correctly shows this molecule? Red middle ball with 2 smaller white balls attached to both sides Which statements are true about ions? Select all that apply. Anions have more electrons than protons, giving them a negative charge. Cations have more protons than electrons, giving them a positive charge. The attraction between atoms with opposite electrical charges forms what type of bond? ionic bond Which of the following are atomic ions? Select all that apply. Cl- O2- Ca2+ Which statement best describes a compound formed by an ionic bond? neutral Which of the following are simple molecular ions? NH4+ CO32- NO3- Which of the following properly describes an ion? an atom or molecule that has lost or gained one or more electrons In one molecule of SO2, two oxygen atoms connect to a central sulfur atom. The three atoms form an angle. Which model correctly shows this molecule? Small yellow ball in the middle with an "S" on it and 2 red bigger balls on each side of it with "O" on it Which statements are true about molecules? Select all that apply. 0.5 of 1 They are the smallest unit of an element or a compound. They are a group of atoms that are strongly joined. What charge does a cation have? an overall positive charge A salt is formed during a reaction of sodium and chlorine ions. Which type of bonding occurred? ionic bond How do ions form? from the gain or loss of electrons Nitric acid is a chemical that is used in the production of fertilizers. The chemical formula of nitric acid is HNO3. Which of the following are true for a nitric acid molecule? Select all that apply. 0.25 of 1 It has three oxygen atoms. It has three atoms. Lesson 3: Lesson 3: What is molecular polarity? the distribution of partial charges among the atoms in a molecule Which statement correctly describes the reason for the high specific heat of water? Water has unusually strong hydrogen bonding. These bonds require extra energy to break. Therefore, water has a high specific heat. Which options describe the structure of a water molecule? Select all that apply. the molecule has an overall bent shape the hydrogen atoms are attached to the oxygen atom at an angle Read the information below. Then use it to answer the following question. A car's tires feel a lot of force when they pass over holes or bumps in a road. Shock absorbers help dull the force coming from the road so that a vehicle shakes less in response. This makes the ride for passengers within the car smoother and more pleasant. The analogy below compares the relationship between pH and specialized chemicals. Choose the answer that best completes this analogy. _[blank]_ : solution pH :: shock absorbers : vehicle movement buffers What happens when the pH of a biological system gets too low? Enzymes may lose their ability to carry out reactions because their shape changes. Which statement correctly describes the bonding between water molecules? The hydrogen atoms have a partial positive charge and are attracted to the oxygen atom in another molecule, which has a partial negative charge. What substance helps organisms to maintain their pH balance? XXX WRONG XXX bases Which of the following substances produces hydrogen ions (H+) when mixed with water? acid Read the passage. Acid-water solutions taste _[blank 1]_. Acids react with _[blank 2]_ to produce salts and water. Which option correctly fills the blanks in the passage? sour; bases Read the statements. In liquid water and ice, the hydrogen atoms on each molecule have a partial _[blank 1]_ charge. The oxygen atom of each molecule has a partial _[blank 2]_ charge. Which options correctly fill the blanks in these statements? positive; negative Which one of water's unique properties allows living organisms to maintain a constant internal temperature? XXX WRONG XXX it becomes less dense when frozen What statement about enzymes and pH is true? Enzymes require a specific range of pH values to function. Which of the following substances tastes bitter and tends to produce hydroxide ions (OH-) when mixed with water? bases Which are unique properties of water? Select all that apply. high heat of vaporization polar high specific heat What statement is correct about the polarity of a water molecule? The oxygen side has a partial negative charge and the hydrogen ends have partial positive charges. Which statements are true about polymers? Select all that apply. Polymers are often made from repeating units. Polymers are long chains. Study the model showing the structure of a polymer. Which model best represents the small molecule that forms this polymer? 1 hexagon and 1 pentagon What are the roles of carbohydrates in living organisms? Select all that apply. providing strength as a structural component providing energy storing energy What is the structure of triglycerides? three fatty acids attached to a glycerol What is the main role of the sugar deoxyribose? It makes up part of the DNA. What happens to an animal that lacks food? The cells of the animal cannot work properly, and the animal eventually dies. How does eating food benefit an animal? Select all that apply. 0.67 of 1 The animal gets water from the food. The animal gets energy from the food. What describes the role of fats in the body? Lipids help form cell membranes and also store energy. Which statement best describes the role of phospholipids in the cells of living organisms? They act as the building blocks for cell membranes. Which of the following are true of trans-fatty acids? Select all that apply. 0.25 of 1 often created by treating plant oils with hydrogen occur naturally in in food What type of fatty acid molecule is covered with as many hydrogen atoms as possible? saturated fatty acid Which of the following are carbohydrates? Select all that apply. glycogen starches sugars Which molecules contain only carbon, hydrogen, and oxygen? Select all that apply. glucose carbohydrates Why do animals need to take in oxygen? to break down fuel molecules Study the model showing the structure of a polymer. What is true about this polymer? This polymer consists of two different monomers. Which molecule is a source of carbon, hydrogen, and oxygen atoms for making proteins? carbohydrates What is a polymer? XXX WRONG XXX a large molecule made of smaller molecules joined together, always in a repeating pattern Lesson 5: Lesson 5: What is an amino acid? an organic molecule that is a building block of proteins Which of the following are functions of proteins? Select all that apply. building and repairing cells forming part of the cell membrane's structure regulating cell processes What protein speeds up chemical reactions? enzyme Which statements describe the function of nucleic acids? Select all that apply. They provide instructions that tell cells how to make proteins. They store and transmit genetic information for all life's processes. Study the image. Which part of the diagram illustrates a protein? A