BIOL 1107 Final Exam (Answered) Complete Verified Solution 100%

BIOL 1107 Final Exam (Answered) Complete Verified Solution 100% The interior region of a phospholipid bilayer is characterized as: Hydrophobic The movement of water across a cell plasma membrane into or out of a cell is an example of: Both osmosis and diffusion. In the example of secondary active transport, what would happen if ATP suddenly became unavailable for Step 1 in Panel a. of the figure shown? The movement of the molecules through the anti-porter would continue for a while until the proton gradient was depleted. A phospholipid molecule in a membrane can: Both spin (rotate around its vertical axis) and move side-to-side (lateral movement). A protein that is temporarily associated with a biological membrane is a(n): Peripheral membrane protein Predict how phospholipids would arrange if they were placed in a non-polar solution rather than a polar solution like water: The phospholipid tails would orient toward the solution, and the heads would cluster away from the solution. Which type of fatty acids would be likely to participate in the greatest amount of van der Waals forces with other fatty acids? Fatty acids with: Long tails and high saturation. Considering the amino acids that are found in various domains of transmembrane proteins, which statement would be true? Non-polar amino acids would be prevalent in the transmembrane domain, in contact with the environment of the inner membrane. When we say that the cell is the fundamental unit of life, we mean that: (All of these choices are correct). All living things are made up of one or more cells. The smallest entity that can be considered living is a cell. A single cell can carry out all life processes. Life doesn't exist in the absence of cells. Why does active transport of molecules across a membrane require ATP? An input of energy is needed to allow the movement of molecules from an area of low concentration to an area of higher concentration. In general, colder temperatures would tend to reduce the fluidity of membranes. In response, cells can adjust the composition of their membranes to maintain the proper degree of fluidity. How would the membrane change in response to colder temperatures? The amount of unsaturated triacylglycerols would increase. Which of the statements represents the flow of information as described by the central dogma of molecular biology? Information in DNA is transcribed into RNA, which carries the information to make protein. Which one of the nucleotides could base pair with a pyrimidine? Adenine A boy observes a robin outside of his window, he notices the robin repeatedly cocks its head to one side before pecking the ground. The boy suspects that when the robin cocks its head it is actually listening for worms or insects underground. His explanation of the bird's behavior is an example of: A hypothesis. Sort the following molecules by how easily they pass through the plasma membrane from most permeable to least permeable. CO2, H2O, C6H12O6, NA+ Samples of three different triacylglycerols were tested to determine the melting point of each one. The length of the fatty acids in A, B, and C is the same. Which of the three fatty acids is likely to have the most unsaturated fatty acids? Type 1 The three main groups, or domains, of organisms are: Bacteria, archaea, and eukarya. How many water molecules would be produced in making a polypeptide that is 14 amino acids long? 13 In general, colder temperatures reduce the fluidity of the membrane, so cells will produce different molecules to maintain the proper degree of fluidity. How would the membrane change in response to colder temperatures to maintain homeostasis and restore the proper degree of fluidity? The amount of unsaturated triacylglycerols in the phospholipids would increase. Paramecium is a unicellular organism that lives in fresh water. Suppose you are studying two populations of this organism: one population lives in a pond in northern Ontario, Canada, and the other lives in a pond in southern Florida. If you examined the plasma membranes of both of these populations at the same time of year, what difference would you expect to find between the two populations' cell membranes? The fatty acid side chains in the membrane phospholipids of the Florida Paramecia would generally be longer and would be more saturated compared to the Canada Paramecia. The ACE-2 receptor that binds to the SARS-CoV-2 virus is a transmembrane receptor. The amino acid sequence of this reveals a polypeptide chain that has one hydrophobic region. Based on this information, what can you conclude about how the protein is associated? The receptor is likely to span the membrane one time. How many hydrogen atoms are present in a hydrocarbon chain of five atoms joined to each other by single covalent bonds? 12 What is pumped across the lysosomal membrane by a transport protein to create a special internal environment in the lysosome? H+ Samples of three different triacylglycerols were tested to determine the melting point of each one. The number of double bonds in each of the fatty acids A, B, and C is the same. Which of the fatty acids is likely to have the most saturated fatty acids? Type 2. Which choice most accurately describes the ratio of oxygen to carbon to hydrogen in a simple 6-carbon sugar such as glucose? 1:2:1 Disorders of which organelle are often associated with defects in transport from compartment to compartment, resulting in poor sorting of protein components within the cell? Golgi apparatus. A phosphodiester bond is formed between: A 5' phosphate and a 3' hydroxyl group of two nucleotides. Which substance could most easily cross a synthetic membrane composed of only phospholipids? Oxygen Which feature of glycosaminoglycans best relates to its function? GAGs consist of multiple carbohydrate molecules that are negatively charged. The plasma membranes of some plant cells use transport proteins to move protons out of the cell against their concentration gradient. This is an example of: Active transport. Refer to the image. The molecule shown here is: An amino acid. How do cells connect to the extracellular matrix? Integrins Which actions would affect the secondary structure of a protein? Breaking the hydrogen and ionic bonds between amino acids. Some plant cells use ATP to create a high concentration of protons outside the cell. This gradient is then used to move solutes, such as sucrose, across the plasma membrane into the cell where the sucrose concentration is already relatively high. The type of transport used to move sucrose is an example of: Secondary active transport A mutation in ___ results in a change in ___ that sometimes produces a ___ with altered structure and function. DNA; RNA; Protein. Which of the following accurately describes the path traveled by a new protein as it is synthesized and released from the cell? Ribosome >> ER >> Golgi >> Vesicle >> Plasma membrane >> External environment Which one of the nucleotides could base pair with a pyrimidine? Guanine Which one of the nucleotides could base pair with a pyrimidine? Guanine Imagine you have discovered a new species of bacteria. To begin your investigation of this organism, you run an assay on the total nucleotide content of the bacterial DNA. If the cytosine content of DNA from the bacterial cells is 40%, what is the adenine content? 10% In which of these examples is entropy definitely increasing? Melting ice in a glass of lemonade. Which type of junction is characterized by the following? 1. Made up of 6 connexin proteins 2. Allows small ions and molecules to pass from one cytoplasm directly into another 3. Used for fast communication between cells Gap junction Which of the following is considered an integral membrane protein? A protein with one end of the protein in the cytoplasm and its other end in the extracellular space. Hydrophobicity is the unifying feature of which type of macromolecule? Lipids You test the pH of a solution in the lab and find it to be 6.0. To lower the pH of this solution to 4.0, you should add ___ and this solution would then be a strong ___. OH-; acid. A patient of yours has a disorder (not hemophilia) that is preventing their blood from clotting properly. You take a biopsy and look under the microscope. You observe that the ECM seems to be deteriorating and the components within the ECM are not binding to each other. Which of the following molecules do you think is most likely to be malfunctioning based on your observations? Fibronectin Which of the following best summarizes the relationship between dehydration reactions and hydrolysis? Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers. Suppose you are studying the transport of a certain polar molecule across the plasma membrane of cells in culture. Over a period of time, you measure the concentration of this polar molecule inside and outside of the cells. You find that the concentration of the molecule was initially lower in the cell but is gradually increasing. You measure the ATP concentration inside the cell and find that it is not changing. Which of the following is probably responsible for the transport of this polar substance in the cell? Facilitated diffusion When you eat a hamburger, some of the energy in the food is converted to ATP that your cells can use to do all kinds of work, some of the energy is stored for later use, and some of the energy is dissipated as heat. This is a consequence of the: Second law of thermodynamics Suppose there is an animal cell with no cholesterol in its plasma membrane. What would happen to the membrane if the temperature were to drop? The membrane would become less fluid more quickly. Researchers seldom find prokaryotic cells that are greater than 100 micrometers in diameter. Why would the size of prokaryotic cells be restricted? Prokaryotic cells must absorb all of their nutrients from their environment and therefore require a high surface area to volume ratio.