Bio 256 Exam 2 (100 out of 100) Questions and Verified Answers (Download To Score An A).

Bio 256 Exam 2 (100 out of 100) Questions and Verified Answers (Download To Score An A). The part of the neuron that normally receives stimuli is called dendrite Depolarization means the inside of the cell gets more positive. The resting membrane potential is largely preserved by the sodium potassium ATPase pump. Inside an activated cell, Na+ and Ca++ are higher in concentration than in the resting state. With electrical synapses, a signal is sent from a presynaptic neuron to a postsynaptic neuron via gap junctions What is the function of acetylcholine in a neuromuscular junction? It enters to myofiber, causing the myosin-actin interaction of a contraction. Which regular, rhythmic low-amplitude brain waves indicate an idling brain? alpha waves Which characterizes the fourth stage of sleep in the sleep cycle? EEG pattern is dominated by delta waves; skeletal muscles are relaxed; arousal difficult Fact memory is the ability to learn specific information. Activation of the reticular activating system results in wakefulness Which inhibits inspiration? pons pneumotaxic center Preparing the body for the "fight-or-flight" response is the role of the sympathetic nervous system Sympathetic fibers leave the spinal cord in the thoracolumbar region, and the postganglionic fibers secrete norepinephrine. Potentially damaging stimuli that result in pain are selectively detected by nocioceptors Which skin receptors detect pain? nocioceptors Over 1000 "smell" genes have been identified for detecting different odorants. Each "odor" you smell stimulates only one of the binding chemicals coded by these genes. false Information from balance receptors goes directly to the brain stem reflex center The sodium-potassium ATPase pump pumps three sodium ions out of the cell and two potassium ions into the cell. Choose the most accurate statement about sound. A ten-decibel increase represents a tenfold increase in sound intensity. Which structure regulates the amount of light entering the eyeball? iris Presbyopia is NOT the unequal curvature of refracting surfaces. The optic radiations project from the ___ to the ___. thalamus, primary visual cortex Which is the most accurate description of how action potentials work? ligand gated ion channels open --> voltage gated sodium channels open --> voltage gated potassium channels open -->voltage gated sodium channels close --> voltage gated potassium channels close There are little rocks (limestone or CaCO3) in our ears. true Why does most of the pain usually stop as soon as a splinter is removed from your skin? Why do you notice this right away? Pain receptors are tonic and there is no adaptation. The nervous system can overide normal endocrine controls. true Which steroid hormone can induce gluconeogenesis in the liver? cortisol ___ is the fasting hormone; ___ is the fed hormone. Glucagon, insulin Growth hormone promotes long bone growth during the formative years. As an action potential reaches its peak, which cellular gates are opening? potassium What is saltatory conduction in a neuron? Is it fast or slow? Saltatory conductions describes how an action potential jumps from node to node in a myelinated fiber. It is fast. If one incoming impulse causes several outgoing nerve impulses, we know that there is a diverging circuit Alpha1 receptors respond to ____ and ____ smooth muscles of various blood vessels including those of the kidneys. Norepinephrine (NE), constrict Which type of receptors fire quickly when first stimulated but then slow their firing to adapt to the stimulus? Phasic Which taste sensation detects alkaloids such as quinine and nicotine? bitter Salty tastes are converted to nerve impulses by na+ influx into detecting cells Which can directly cause the round window to bulge when there is increased pressure? Scala tympani Second messengers, such as cyclic AMP, activate or inactivate intracellular enzymes The part of a neuron that conducts impulses away from its cell body is called a(n) axon We have an expert-written solution to this problem! Membrane hyperpolarization means the inside of the cell becomes more negative than the resting potential The resting membrane potential is characterized by high potassium and protein inside the cell, and high sodium and calcium outside of the cell An action potential is propagated by opening of voltage-gated sodium channels Saltatory conduction is made possible by the myelin sheath. select the correct statement about synapses the synaptic cleft prevents an impulse from being transmitted directly from one to another Which hormone reduces blood pressure? Atrial Natruiretic Peptide (ANP) Glucocorticoids enable the body to deal appropriately with stress. They accomplish this by Increasing blood glucose, fatty acid, and amino acid levels and enhancing blood pressure We have an expert-written solution to this problem! Mineralocorticoid is to aldosterone as glucocorticoid is to Cortisol Which ion is in higher concentration inside the cell as compared to outside? K+ How can you tell if a person is in an REM stage of their sleep? Their eyeballs are moving so much you can see this through their eyelids Sympathetic responses generally are widespread because Norepinephrine acts indirectly through a second messenger (slower) Which is NOT connected by the helicotrema? scala media You would expect _____ to be stimulated as you take an elevator up. These extend from the vestibule into the _____. Saccular, cochlea How does a gustatory cell respond to sour tastes hydrogen ions block the potassium channels, depolarizing the membrane When a skin areas two point threshold is SMALL, that skin has High sensory acuity Which is NOT detected by a mechanoreceptor type? taste Autonomic ganglia contain... the cell bodies of motor neurons A second nerve impulse cannot be generated until The resting membrane potential has been reestablished Membrane receptors use _______ to transduce a signal to the intracellular compartment G-proteins which is an incorrect matching of a brain component with its function parietal lobe, control of motor function Which is the correct order of events from resting through a neuron action potential? Polarization, depolarization, hyperpolarization Neurotransmitter is released from rods and cones in the dark Which is not true about voltage gated ion channels? ions will diffuse to the area of higher ion concentration through the channel The first "way station" in the visual pathway from the eye, after there has been partial crossover of the fibers in the optic chiasma, is the lateral geniculate body of the thalamus We have an expert-written solution to this problem! Photoreceptors package visual pigment in membrane-bound discs, increasing the efficiency of light trapping When you relax your ciliary muscles, you can scan the horizon and watch the sunset There are three layers of neurons in the retina. Which cells detect dim light and are used for peripheral vision? rod ells We have an expert-written solution to this problem! Light passes through the following structures in which order? cornea, aqueous humor, lens, vitreous humor The receptor for static equilibrium is the utricle Odor signals are processed and sent to the olfactory cortex by mitral cells Bitter tastes are converted to nerve impulses by closing the potassium channel directly Which provides the ultimate control for the sympathetic nervous system? hypothalamus In contrast to the somatic nervous system, the autonomic nervous system has two efferent neurons The brain area controlling wakefulness or alertness is the reticular formation Which statement is true about short-term memory? It only last from a few seconds to a few hours. When most dreaming takes place, your sleep is characterized by temporary skeletal paralysis, except for the extrinsic eye muscle Brain wave amplitude reflects the number of neurons firing synchronously A neuronal circuit that concentrates or directs a large number of incoming impulses to a rather small number of neurons is called a(n) Converging circuit What is the function of acetylcholine in a neuronmuscular junction? It diffuses across the synapse, binding membrane receptors, stimulating an action potential in the myofiber Direct-acting neurotransmitters open ion channels to cause rapid responses with electrical synapses, a signal is sent from a presynaptic neuron to a postsynaptic neuron via gap junction Which sense perception does NOT involve the thalamus? smell All reflexes involve only an afferent and an efferent neuron false second messengers, such as cyclic AMP activate or inactivate intracellular enzymes In autocrine signaling the signaling substance effects the secretory cell far-sightedness associated with aging is called presbyopia There are three layers of neurons in the retina. The axons of which of these neuron layers form the optic nerves? ganglion cells The hearing receptor is the organ of Corti The second messenger used for detecting the presence of an odorant molecule cAMP Sweet tastes are converted to nerve impulses by A G protein gustaducin transducing the sensation Which is not true about the dorsal column medial lemiscal pathway? Many axons cross over to the opposite side of the body in the spinal cord Which skin receptors detect texture and vibrations? Meissner's corpuscles Which is regulated by only the sympathetic, not parasympathetic, branch of the autonomic nervous system? arrector pilli muscle Alpha2 receptors respond to ......., and ........ digestive enzyme release to the small intestine. norepinephrine, inhibiting Which is innervated by the somatic nervous system? skeletal muscle Which is true about PET scans? They detect increased or decreased metabolic activity by measuring the uptake of radioactive deoxyglucose Which area largely controls the brains ability to understand language? Wernicke's area of the Cerebrum. Which part of the nervous system controls survival emotions and behavior? The limbic system Which irregular rhythmic brain waves are observed when you are awake and alert? beta a neural circuit with input traveling along several pathways for integration by several CNS systems and providing several response is a parallel processing circuit The period after an initial stimulus when a neuron is not sensitive to another stimulus is the refractory period