Bio 473 Theory Exam 1 Verified Study Solutions With Complete Updates

Neurotransmitters - CORRECT ANSWER-- Neurons talk to each other by exchanging molecules called neurotransmitters - The neurotransmitters are released from one neuron, travel across the synapse between the two neurons, and bind to receptors on the other neuron. The neuron that delivers the message is called the pre-synaptic neuron and the neuron that receives the message is called the post-synaptic neuron Action Potential and Neurotransmitters - CORRECT ANSWER-- The signal for the release of neurotransmitters is called an action potential 1. Action Potential propagates down the axon of the neuron 2. Action potential reaches the axon terminus and causes the stores of neurotransmitters to move the cell membrane at the synapse 3. neurotransmitter is released into the synapse 4. neurotransmitter is recieved by the receptors 5. An action potential is initiated in the post-synaptic neuron 6. Left over neurotransmitter is take back to storage in the pre-synaptic cell via their transporter in a process known as "reuptake" *Neurotransmitter determines length of the signal membrane potential - CORRECT ANSWER-- All cells, including neurons, are relatively more negatively charged on the inside, compared to the outside environment. When the charged ions cross the membrane via protein channels, the voltage of the membrane changes. Seizures - CORRECT ANSWER-- Seizures are sudden changes to the electrical signals that cause elevated signaling in the brain - Seizures can be caused by any of the following: an imbalance of the voltage of the cell membrane due to changes in the ion channels; an imbalance in the release of neurotransmitters; changes to how many neurotransmitter receptors are expressed on the post-synaptic membrane; an imbalance in neurotransmitter reuptake; Graded Potentials - CORRECT ANSWER-- occur on dendrites, cell body - depolarizations and hyperpolarizations - weaken as they move from the source - may or may not depolarize neuron to threshold Action Potentials - CORRECT ANSWER-- axon and terminals - graded potential depolarizes axon hillock past threshold - travel long distances without losing strength - voltage gated Na+ and K+ channels Action Potential - CORRECT ANSWER-1. Depolarization to threshold 2. Activation of sodium channels and rapid depolarization 3. inactivation of sodium channels and activation of potassium channels Absolute Refratory Period - CORRECT ANSWER-neuron will not generate another action potential and ensure action potential propagation occurs in one direction Relative Refractory Period - CORRECT ANSWER-may generate another action potential if the stimulus is strong enough Encephalography - CORRECT ANSWER-a snapshot of all of the electrical activity (neurons currently firing action potentials) occurring at the surface of the brain. Sensors called electrodes can be used to detect the action potentials. To measure brain activity specifically, the electrodes must be placed on the scalp. Brain Waves - CORRECT ANSWER-There are four main types of brain waves: alpha, beta, theta, and delta. The type of waves a person is producing will vary with their brain activities (awake vs. asleep, relaxing vs. concentrating). Alpha Waves - CORRECT ANSWER-are associated with wakeful relaxation while the eyes are closed. Beta Waves - CORRECT ANSWER-are produced when a person is actively thinking and concentrating on something, typically with their eyes open. Theta and Delta Waves - CORRECT ANSWER-are transitional and not often observed; delta waves are most commonly associated with sleep. EEG Waves Defined By Frequency - CORRECT ANSWER-- Amplitude can be used to further describe a particular wave pattern. Frequency, measured in Hertz (Hz), is the number of waves or cycles per second, and is used as the defining factor to identify a wave type. - It is the frequency that allows us to distinguish a beta wave, which cycles between 13-30 Hz, vs. an alpha wave cycling at 8-12 Hz. - Amplitude is the height of the wave and can be measured in volts (V). While amplitude does not define a wave, it can often indicate a relative increase or decrease in brain activity. Brain waves produced in a specific region of the brain - CORRECT ANSWER-- frontal lobe: beta waves - occipital lobe: alpha waves Conducting Division of the Respiratory System - CORRECT ANSWER-The conducting division of the respiratory system is responsible for ventilation or transporting air between the atmospheric air in the environment and the inside of the lungs The conducting Division: Nose and Nasal Cavity - CORRECT ANSWER-The functions of the nose and nasal cavity are to warm, clean, and humidify the air. The conducting division: The pharynx - CORRECT ANSWER-The pharynx also warms, humidifies, and cleans the inhaled air. The conducting Zone: The larynx - CORRECT ANSWER-the primary function of the larynx is to keep food and drink out of the lungs. The epiglottis is housed within the larynx and works like a drawbridge to regulate airflow; when the epiglottis is in the raised position it permits airflow, and when lowered covers airways and directs food and drink toward the esophagus. The conducting Zone: The trachea - CORRECT ANSWER-- The trachea is a hollow organ connecting the bottom of the larynx to the two bronchi - The trachea functions to clean air and remove any fine dust and debris that escaped the cleansing system in the nasal cavity. Additionally, it is lined with cells that have hair-like projections, called cilia, which beat like oars, moving mucus and any debris caught in it away from the lungs and toward the pharynx Bronchial Tree - CORRECT ANSWER-The trachea diverges into the right and left bronchi, which transport air to each lung. Inside the lungs, each bronchus branches like a tree into smaller bronchi, termed secondary and tertiary bronchi. All bronchi are hollow and transport air to and from specific regions of the lungs. The respiratory bronchioles are the smallest structures and mark the end of the conducting division of the respiratory system. The Respiratory Division - CORRECT ANSWER-The function of the respiratory division of the respiratory system is to allow gas exchange of oxygen and carbon dioxide between the environment and blood. Air that has passed through the bronchial tree and is traveling through a respiratory bronchiole will pass into a bundle of hollow sacs called alveoli (singular alveolus). Gas exchange occurs across the membranes of each alveolus. The Respiratory Division: Alveoli - CORRECT ANSWER-The alveoli in your lungs provide an enormous surface area for gas exchange. The walls of each alveolus are just one cell thick and are surrounded by a net of capillaries. The walls of the capillaries are also just one cell thick. The respiratory membrane is formed where the cells of an alveolus meet the cells of the capillary wall. Gas exchange occurs across the respiratory membranes. The Respiratory Division: The Respiratory Membrane - CORRECT ANSWER-Atmospheric air has a higher concentration of oxygen compared to deoxygenated blood, thus diffusion will occur across the respiratory membrane and oxygen will enter the blood. Similarly, carbon dioxide waste is in higher concentration in deoxygenated blood compared to the atmospheric air. Here diffusion will again take place, but in the opposite direction across the respiratory membrane, into the alveolus and finally returned to atmospheric air. ** Diffusion is higher to lower Pleura - CORRECT ANSWER-- The outer surface of the lungs is covered by a membrane called visceral pleura. The inside walls of the chest are lined by a membrane called parietal pleura. The visceral and parietal pleura are continuous with one another and surround each lung, creating a separate compartment for each lung called a pleural cavity. The pleural cavity is quite narrow and contains a thin liquid called pleural fluid. The Diaphragm - CORRECT ANSWER-- The muscles in the chest and abdomen are responsible for moving the chest wall and abdomen to change the volume of the lungs and, therefore, the alveoli. The volume of the alveoli is known as the intrapulmonary space. - The most important muscle controlling respiration is the diaphragm. The diaphragm is a dome-shaped muscle that divides the thoracic cavity from the abdominal cavity. The diaphragm does not attach directly to your lungs. It is attached to the parietal pleura in the same way as the chest wall. Volume Pressure Relationship - CORRECT ANSWER-- The pressure of the air in the environment is called the atmospheric pressure. Air moves into and out of the lungs because of differences in pressure between the environment vs the inside of the lungs. The pressure of the air inside the lungs is called the intrapulmonary pressure. - Boyle's law states that the pressure of a given quantity of gas is inversely proportional to its volume. Volume is the amount of space inside of any container (a syringe, a sack, or a lung). Therefore, according to Boyle's law if the volume of a container increases, the pressure of any gas or liquid inside that container will decreas Lung Mechanics - CORRECT ANSWER-- muscles work to increase the volume of the lung and a pressure differential is created. As a result, air moves into the lungs. When atmospheric pressure is higher than intrapulmonary pressure, then air will enter the lungs (this is inhalation). - When intrapulmonary pressure is higher than atmospheric pressure, then air will leave the lungs (this is exhalation). Respiratory Control Center - CORRECT ANSWER-the circuit of neurons in the base of the brain (the medulla oblongata and pons) that control the rate and depth of your breathing. Motor neurons leaving the respiratory control center innervate the diaphragm and chest muscles, causing them to contract and drive respiration. The respiratory control center also receives input from many other neurons. Peripheral Chemoreceptors - CORRECT ANSWER-- monitor the carbon dioxide (CO2), hydrogen ion (pH), and oxygen (O2) concentrations in blood, and adjust the depth and rate of breathing accordingly. Carbon dioxide or CO2 is a waste product produced by all cells of the body during metabolism. Of the three chemicals listed, CO2 and H+ concentration have greatest impact on regulation of breathing. CO2 and pH levels in blood - CORRECT ANSWER- Hypercapnia - CORRECT ANSWER-- a condition where the CO2 concentration in blood is too high - The carbonic acid equation will run forward, as all the reactants reach a new equilibrium, and H+ ion concentration increases. The increase in H+ ion concentration increases the acidity of your blood, and can cause the condition respiratory acidosis (when the blood is too acidic). Hypercapnia and respiratory acidosis usually occur together. The respiratory control center will respond by increasing how fast and deep you are breathing. This will cause CO2 to diffuse from your blood and into your lungs more rapidly. CO2 levels will decrease, the carbonic acid equation will run in reverse or to the left, and H+ ion concentration will decrease as well bringing the body back to a safe CO2 level and pH. Hypocapnia - CORRECT ANSWER-a condition where CO2 concentration in blood is too low. In this case, the carbonic acid equation will run in reverse or to the right, and H+ ion concentration will decrease as a new equilibrium is reached. The decrease in blood H+ concentration will cause the blood to be less acidic. This condition is called respiratory alkalosis. Hypocapnia and respiratory alkalosis usually occur together. To correct the situation, the respiratory control center will decrease your respiratory rate. By breathing more slowly, CO2 from your cells will have a chance to build up in your bloodstream. The CO2 concentration will rise, and the carbonic acid equation will run forward again, reversing the respiratory alkalosis Hydrogen Levels in CSF - CORRECT ANSWER-- The most important factor controlling respiration is the H+ ion concentration of the cerebrospinal fluid (CSF), the fluid bathing the brain. Central chemoreceptors found in the me