Biol 141 Exam Questions With Solution

Biol 141 Exam Questions With Solution A blood cell is placed into a solution which contains more solutes than the cytoplasm of the cell. The solute cannot travel across the membrane but water can. Which scenario will occur? - Cell will gain water and swell - Cell will lose water and shrink - Cell will stay the same size - Answer -Cell will lose water and shrink /.A chain of amino acids is coiled around and around in the shape of a spring is an example of.... - Answer -secondary structure /.A drug binds to and inhibits protein pumps (enzyme pumps that use ATP) of a cell. What is one result of this event? - Passive transport will not occur - Solutes will not move down concentration gradient - Primary active transport will not occur - Facilitated discussion will not occur - Answer -Primary active transport will not occur /.A neurotransmitter from a presynaptic neuron causes an inhibitory postsynaptic signal (IPSP) in the postysynaptic neuron. Which if the following events will occur FIRST - Potassium ligand-gated channels open - Sodium-gated ligand channels open - An action potential is initiated in the postsynaptic neuron - The postsynaptic neuron will hyperpolarize - Answer -Potassium ligand-gated channels open /.A saturated fat has _____ fatty acid and ____ glycerol - Answer -3 fatty acid and 1 glycerol /.A series of membrane sacs that processes and packages newly synthesized proteins is the.... - Answer -golgi apparatus /.Are potassium or sodium channels more permeable? - Answer -POTASSIUM /.Depolarization of a neuron plasma membrane will shift the membrane potential toward _____ - Answer -0mV /.During a hyper-polarizing local potential an interneuron.... - The potential becomes _______ positive - _______ ligand-gated channels open - T or F: An action will be triggered - T or F: The local potential will be communicated to the next neuron - Answer -less ; potassium ; false ; false (action only triggered during depolarization) /.f you drink a large amount of water, your interstitial fluid may become_________compared to your intracellular fluid (assume that there has not been a major change in the solute/solvent concentrations of intracellular fluid). - isotonic - osmotic - hypertonic - hypotonic - Answer -hypotonic /.Fatty acid tails are hydro_______ and the heads are hydro_______ - Answer -tails are hydrophobic heads are hydrophilic /.How long does it take for glycogen to run out? - Answer -90 minutes of running /.How many amino acids make a protein? - Answer -20 amino acids /.How many ATP are generated per glucose molecule in the Kreb's cycle? - Answer -34-36 /.how many grams of glycogen needed daily to meet demands of the brain? - Answer -100g /.How to increase levels of HDL? - Answer -Whole grains, high fiber fruit, fatty fish, flax, nuts, chia, avocado, EXERCISE /.If a ligand binds to a ligand-gated Na+ channel in the membrane of a neuron, which way will sodium diffuse? - Answer -into the cell /.If the membrane is permeable to potassium ions, which way will they diffuse? - Answer -out of the cell /.If the membrane is permeable to sodium ions via leak channels which way will they diffuse? - Answer -they will diffuse into the cell /.In the quarternary stage of the protein... - Answer -several proteins are working together /.Injured tissue releases chemicals which activate platelets in the blood. Activated platelets release chemicals to attract MORE platelets, eventually forming a blood clot. The signal ends. What is this an example of? - Answer -positive feedback loop /.Phospholipid heads are _______ and the tails are ________ - Answer -hydrophilic ; hydrophobic /.Protein shape changes the ________ - Answer -function /.Proteins are the polymer of________ and have specific functions based on what? - Answer -polymer of amino acids; functions based on protein folding NOT based on carboxyl group /.T or F: A positive feedback loop causes a self-amplifying cycle where a physiological change leads to even greater change in the same direction - Answer -true /.T or F: An excitatory postsynaptic potential is always depolarization - Answer -true /.T or F: Low Density lipids dissolve in blood - Answer -false; think of cholesterol - must be flushed out by HDL /.T or F: Phospholipid molecules connected to make membranes, with tails poining out towards water and heads pointing towards cell away from water - Answer -false /.T or F: Phospholipids are made up of 3 fatty tails connected to a glycerol head, nothing else - Answer -False /.T or F: There are more anions inside of a cell membrane than outside that help establish RMP. - Answer -true /.Three classes of protein folding: - Answer -Globular, fibrous, membrane /.What are carbohydrates important for? - Answer -Kreb's Cycle (cellular respiration) basic source of energy in animals sugar storage in animals polymer of glucose is stored in liver → maintains fuel for brain, kidneys, etc /.What are different types of fatty acids? - Answer -saturated fatty acids and unsaturated fatty acids /.What are low density lipoproteins (LDL)? - Answer -bad cholesterol Doesn't dissolve in blood Proteins carry cholesterol (LDL) and displaces it on arteries as plaque ex bacon grease /.What are phospholipids composed of? - Answer -1 glycerol, 2 fatty acids, phosphate group /.What are saturated fats found in? - Answer -found in meat and dairy products and are much harder to break down in the body → can stay in body longer /.What are the functions of triglycerides? - Answer -energy storage and insulation