Portage Learning A&P 2: Final EXAM 2024/25

Portage Learning A&P 2: Final EXAM Collection of cell bodies found in the peripheral nervous system: - Ganglia This part of the autonomic system increases digestion. - parasympathetic The ventral root of a nerve contains what type of neurons - motor (efferent) Part of neuron that conducts nerve impulse away from cell body - Axon A neuron going to bicep of the forearm is part of the - Peripheral/ Somatic T/F: Neurons come into direct physical contact w/ one another. - False: don't physically touch. Describe function and release of neurotransmitters - Neurotransmitters are chemicals stored inside secretory vesicles (axon terminal vesicles) at the end of the axon terminals. When neurotransmitters are released by the axon terminal vesicles, they carry the transmission of the nerve impulse from one neuron to another. An efferent neuron carries information: - From the central to the peripheral nervous system An afferent neuron carries information: - From the peripheral to the central nervous system. An interneuron inside the spinal cord is part of the: - central nervous system Describe the synthesis and storage of neurotransmitters: - The neuron cell body manufactures neurotransmitters, which are stored in secretory vesicles at the end of axon terminals. A postsynaptic neuron would be found - after the synapse what is the location and function of satellite cells - location: peripheral nervous system function: regulate the environment of neuron cell bodies. what is the location and function of astrocytes - location: central nervous system, the brain function: forms the blood, brain barrier A patients left thumb was severed in a cooking accident and then reattached during surgery. Would the patient be expected to regrow axons in their thumb? Why? Why not? - Yes. Peripheral nerves can regenerate the length of an axon through axonal regeneration because of the growth of Schwann cells ahead of the axon. At rest, a neuron plasma membrane is: - Polarized (around -70mV) Which of the following is false concerning the sodium-potassium pump? - The overall effect is a negative charge on the outside of the membrane. Which of the following is true concerning the sodium-potassium pump? - It must remain in constant operation to maintain resting state. T/F : A sensory neuron is signaling the body of extreme pain. This means that the strength of the action potential is greater than usual. - False. There is no variation in the strength of the action potentials. (all or nothing) There is a variation in the number and frequency of neurons firing. Which of the following statement is false concerning the neuromuscular junction? - ACh is released from the presynaptic motor neuron to cause an action potential in the muscle fiber. Which of the following is true concerning the neuromuscular junction? - The NMJ terminates on a muscle fiber. How is a message sent from one neuron to another? - There is a minute fluid-filled space, called a synapse, between the axon terminal of the sending neuron and the dendrite of the receiving neuron. When a nerve impulse reaches the end of an axon, neurotransmitters are released into the synapse. These bind with a receptor on the next neuron, opening Na+ gates in the receiving dendrite which causes depolarization and the impulse is carried. Synapse! What neurotransmitter is found in the neuromuscular junction? - ACh, Acetylcholine What neurotransmitter helps regulate emotional responses and muscle tone? - Dopamine In a reflex, the ___________ neuron conducts nerve impulses along a pathway towards the central nervous system. - Sensory (afferent) T/F: Action potentials travel in one direction within the same neuron. - True T/F: Reflexes occur only with conscious intervention from the brain. - False In a reflex, the __________ neuron conducts nerve impulses along a pathway to create a response. - Motor (efferent) This is part of a reflex is inside the CNS, made up of one or more synapses. - the integration center Where is the integration center of a reflex located? - CNS (central nervous system) Which of the following is true about reflexes? - Regulation of blood sugar by hormones is one example of a reflex. What is false about the flexor withdrawal reflex? - It does not involve interneurons. The effect of the reflex is to create a co-contraction of two muscles What is true about stretch reflexes? - The muscle spindle detects the stretch within the muscle. What is true about the flexor withdrawal reflex? - It involves excitatory interneurons. It involves inhibitory interneurons. You touch a hot pan when cooking. List out the steps, in detail, of the nervous pathway of the reflex that occurs. Include any sensory organs involved and the action of the reflex. - Flexor withdrawal reflex: - Pain receptor in skin. - Sensory (afferent) neuron through DRG - Interneurons in spinal cord - (1) Excitatory to biceps - (2) Inhibitory to triceps - Motor neurons: contract biceps, inhibit triceps - Action: Elbow flexion pulls hand away Your doctor taps on your patellar tendon. List out the steps, in detail, of the nervous pathway of the reflex he is testing. Include any sensory organs involved and the action of the reflex. - - Stretch on patellar tendon. - Muscle spindle detects stretch. - Sensory (afferent) neuron through DRG - Interneurons in spinal cord - Synapses directly on a motor neuron - Action: Quad contracts kicking foot out Multiple sclerosis is an autoimmune disease which attacks the myelin sheath of the nerve axon. Patients with this disease may experience difficulty using the muscles of their arms and legs. Explain why this occurs. - Myelin increases nerve conduction speed and protects the nerve. If the myelin is damaged, the conduction speed would be slower than normal, and the nerve axon itself would be vulnerable to permanent damage without the myelin present for protection. Botulism is a disease caused by a neurotoxin that interferes with the release of Acetylcholine. Patients with this disease experience flaccid paralysis, or the inability to contract their muscles. Explain why this would occur. - Acetylcholine triggers the release of sodium ions. The sodium ions reach the