BIO 350 EXAM 1 QUESTIONS ANSWERED CORRECTLY LATEST UPDATE 2026

BIO 350 EXAM 1 QUESTIONS ANSWERED CORRECTLY LATEST UPDATE 2026 Physiology - Answers the study of life, specifically, how cells, tissues, and organisms function Homeostasis - Answers process by which organisms maintain a relatively stable internal environment Internal Milieu - Answers internal environment interstitial fluid - Answers fluid in the spaces between cells intracellular fluid - Answers the fluid contained within cells extracellular fluid - Answers fluid outside the cell Feedback Control Systems - Answers Distinguished on the basis of how the response of the EFFECTOR organ influences an imbalance created by stressors. Set Point (feedback control system) - Answers is the desired level of the controlled variable Integrator - Answers compares signals from the sensor to set point Effector - Answers provides the means for the control center's response to the stimulus Compensatory Response - Answers A biological reaction to a conditioned stimulus that is the opposite of the effects of the stimulus and therefore partially counteracts its effects. Acclimatization - Answers the gradual process by which an animal adjusts to changes in its external environment (takes place in the field or nature Acclimation - Answers Change in physiology or form of an organism in response to changes in environmental conditions (takes place in a controlled environment) Inorganic molecules - Answers molecules that do not contain carbon Examples of Inorganic Molecules - Answers H20 Electrolytes: Ions (Na+, K+, Cl-), Salts (NaCl), Phosphates (PO43-), Acids (HCl), and Bases (NaOH) Gases: O2, CO2, NO (nitric oxide), not N2 Organic Molecules - Answers molecules that contain carbon Examples of Organic Molecules - Answers carbohydrates, lipids, proteins, nucleic acids aerobic - Answers requires oxygen Anaerobic - Answers does not require oxygen Phospholipid Bilayer - Answers a two-layered arrangement of phosphate and lipid molecules that form a cell membrane, the hydrophobic lipid ends facing inward and the hydrophilic phosphate ends facing outward. Concentration Na+, K+, and anions inside and outside of cells - Answers Na+ : interior (10mM) Exterior (120mM) K+: Interior (140) Exterior (2.5) Cl-: Interior (3-4) Exterior (120) A-: Interior (140) Resting membrane potential: What is the typical Em of a mammalian cell? - Answers E=voltage; m=across membrane The electrical potential across the cell membrane The typical Em is (-70 mV) Equilibrium Potential - Answers The membrane potential where the net flow through any open channels is 0. In other words, at Erev, the chemical and electrical forces are in balance. Sodium-Potassium Pump - Answers A transport protein in the plasma membrane of animal cells that actively transports sodium out of the cell and potassium into the cell. (3 Na+ out and 2K+ in) Depolarization - Answers The process during the action potential when sodium is rushing into the cell causing the interior to become more positive. Repolarization - Answers Return to resting potential after depolarization Hyperpolarization - Answers membrane potential becomes more negative Graded Potential - Answers Change in membrane potential relative to resting potential LOCAL changes in membrane potentials Can be of varying magnitudes Direct relationship between magnitude of trigger event and magnitude of depolarization Action Potential - Answers brief, large (100mV) changes in membrane potential Saltatory Conduction - Answers the jumping of action potentials from node to node Electrical Synapses - Answers Action potentials transmitted between 2 cells as if no membranes were present Directly connects the cytoplasm of 2 cells Bidirectional Very fast Chemical Synapses - Answers Use neurotransmitters to send a signal from one neuron to another Unidirectional (presynaptic to postsynaptic) Summation - Answers an accumulation; a total result Excitatory post-synaptic potential (EPSP) - Answers Small post synaptic potential that makes the neurone more likely to fire an action potential temporal vs. spatial summation - Answers Temporal: results from a single presynaptic input Spatial: results from 2 or more presynaptic inputs ganglion - Answers group of nerve cell bodies, often with related functions Cerebrospinal Fluid - Answers the fluid in and around the brain and spinal cord Astrocytes - Answers Provide structural and metabolic support for neurons (most abundant) Oligodendrocytes vs. Schwann Cells - Answers Oligo - in CNS, work on many axons Schwann - in PNS, work on one axon, wrap around many times Microglia - Answers immune defense of CNS Ependymal Cells - Answers forms a network that makes cerebrospinal fluid Afferent vs. Efferent Neurons - Answers Afferent neurons are sensory neurons that carry nerve impulses from sensory stimuli towards the central nervous system and brain, while efferent neurons are motor neurons that carry neural impulses away from the central nervous system and towards muscles to cause movement. Peripheral nervous system: autonomic vs. somatic - Answers somatic nervous system (SNS), which manages voluntary movement of skeletal muscles and external sensory input, and the autonomic nervous system (ANS), which regulates involuntary internal functions like heart rate, digestion, and breathing Pre-ganglionic vs. post-ganglionic - Answers Preganglionic neurons originate in the CNS (brainstem/spinal cord), are myelinated, and release acetylcholine (ACh) in autonomic ganglia. Postganglionic neurons originate in peripheral ganglia, are usually unmyelinated, and innervate target organs, typically releasing norepinephrine (sympathetic) or ACh (parasympathetic) inhibitory postsynaptic potential (IPSP) - Answers an inhibitory hyperpolarization of the postsynaptic membrane of a synapse caused by the liberation of a neurotransmitter by the terminal button Describe why it is important to study comparative physiology - Answers appreciate diversity understand trade-offs and constraints universal vs. unique Understand and give examples of the Krogh Principle - Answers There is an ideal model organism (or system) for studying each physiological process Ex: squid giant axons, fruit flies Understand how feedback control systems maintain homeostasis (and be able to give physiological examples of feedback control systems) - Answers Body systems maintain homeostasis, which is essential for the survival of cells, and cells make up body systems. Read the slides for examples and more explanation Understand how inorganic and organic molecules contribute to the structure and function of animals - Answers Inorganic Molecules (2/3 of body): H2O, Electrolytes, and gases Organic Molecules (1/3 of body): Lipids, carbs, amino acids, nucleic acids Describe how animals generate energy for cellular metabolism - Answers Refers to all the chemical reactions in the body that use or release energy It is the energy balance between synthesis reactions and decomposition reactions in the body Generate energy by doing cellular respiration (look at the slides for more in-depth on this) Describe the structure and functions of the cell membrane - Answers Fundamental Processes: regulation of the intracellular space and regulation of the internal milieu of the Organism (Interstitial fluid) Organization of phospholipids into a bilayer in water Separation of ECF and ICF by the lipid bilayer Understand how and why the fluidity of the cell membrane is altered - Answers 2 ways to change Membrane Fluidity 1) composition of fatty acids - Fluid: unsaturated hydrocarbon tails prevent packing, enhancing membrane fluidity - Viscous: saturated hydrocarbon tails pack together, increasing membrane viscosity 2) cholesterol: distinct effects depending on temperature ("just right") a. warm temperatures (37 °C): chol restrains the movement of PLs and decreases fluidity b. cool temperatures: chol maintains fluidity by preventing tight packing Understand the diffusion and osmotic gradients of the cell membrane - Answers diffusion down a concentration/chemical gradient (no separation/membrane) osmosis: net diffusion of water down its own concentration gradient (to the area of higher solute concentration) Use the Nernst equation to determine the equilibrium potential of an ion - Answers Used to calculate the membrane potential, where the chemical gradient = electrical gradient for an ion (aka equilibrium potential, aka Nernst Potential) based on the valence of the ion, inside and outside concentrations of ions, and temperature-dependent Understand the factors that establish the resting membrane potential - Answers 1) passive diffusion: leaky channels (25x more permeable to K+ vs. Na+)