Biology 30 Midterm EXAM QUESTIONS AND ANSWERS

Explain the event(s) that takes place once maximum depolarization is reached during an action potential - ANS Sodium gates close and potassium gates open allowing potassium to leave the axon How can you distinguish between a light touch and a moderate poke to the arm? - ANS The number of action potentials change depending on the strength of the stimulus identify the area of the brain that is responsible for maintaining homeostasis by regulating the process such as hunger, thirst, body temperature, and water balance - ANS hypothalamus identify the type of neuron that carries impulses toward the central nervous system - ANS sensory neuron if a motor neuron involved in a pain-withdrawal reflex was damaged, what would likely be the symptom(s)? - ANS decreased ability to react to painful stimulus the part of the brain that connects the right and left cerebral hemispheres is called the - ANS corpus callosum the division of the nervous system that is directly responsible for physiological responses to fear is the - ANS sympathetic nervous system because the retina of the komodo dragon consists of only cones, komodo dragons have a limited ability to see - ANS prey in low-intensity light if an eagles brain were similar to structure to a human brain, impulses that begin in the fovea of the eagle's eye would travel to the - ANS occipital lobe strong near and far accommodation in the eye requires - ANS highly developed ciliary muscles which neuron structure enables the nerve cell to regenerate if damaged? - ANS neuilemma which of the following helps maintain a negative resting potential? A. the action of the sodium potassium pump B. the presence of negative chloride ions inside the neuron C. diffusion of sodium ions out of the cell D. All of the above - ANS D. All of the above which of the following is responsible for carrying impulses from the external sensory receptors to the central nervous system and carrying motor commands to skeletal muscles - ANS somatic nervous system which of the following represents the direction a neuron signal travels within a single neuron - ANS dendrite cell body axon axon terminal (synaptic) what would result from the stimulation of sympathetic motor neurons going to the heart, skin and liver? - ANS increased heart rate, decreased blood flow and conversion of glycogen to glucose define hyperpolarization of a neuron, explain two reasons why hyperpolarization is needed - ANS hyperpolarization of a neuron is when there is excess potassium released outside the neuron. 2 reasons why it is needed, it causes the potassium gates to close and it ensures that the impulse does not go backwards towards the body how does donepezil affect synapic transmission - ANS donepezil prevents the breakdown of acetylcholine so that more acetylcholine is available in the synapse conscious efforts to control body responses through biofeedback originate in the.. - ANS cerebellum explain the relationship between the myelin sheath and nerve impulse transmission - ANS myelin sheath and nerve impulse transmission is that the myelin sheath is what protects the myelinated neurons, as well as speeds the rate of nerve impulse transmission damage to the myelin sheath of an optic neuron affects the speed of neural transmission to the visual centre which is found in what part of the cerebrum? - ANS occipital lobe in the human ear, sounds are translated into nerve impulses in the,, - ANS organ of corti insecticides that inhibit the action of cholinesterase kill insects by - ANS causing continuous muscle contraction when a neuron is stimulated at threshold level and hyperpolarization is reached, the time required to return to its original resting electrochemical state is known as the.. - ANS refractory period compare the roles of the sympathetic and parasympathetic nervous systems, provide one similarity and one difference - ANS Sympathetic is fight or flight, increased heart rate/bp. parasympathetic is rest or digest and decreased heart rate. Both are autonomic if a tumor were to destroy a part of the frontal lobe of the cerebrum, most likely there would be a change in.. - ANS personality a nerve impulse is best described as - ANS an electrochemical process ocurring across the neurons membrane if an injured persons heart and respiration rates varied unexpectedly, one might suspect damage to the.. - ANS medulla oblongata define action potential, explain the two parts of action potential - ANS action potential is when the charge in an electrical potential across a neuron membrane is associated with the passage of an entire pulse. two parts of an action potential are repolarization and depolarization paralysis of muscles below the site of a spinal cord injury is often permanent because neurons in the grey matter of the spinal cord all lack a.. - ANS neurilemma structures that carry nerve impulses to the central nervous system are called.. - ANS sensory neurons the bodys response to danger involves the.. - ANS sympathetic system, which increases the size of pupils and decreases peristalsis in the stomach which is a correct description of some sensory receptors in the eye? - ANS cones are concentrated in the fovea of the retina and function to detect colours cryptorchidism is the failure of one or both of the testes to descend from the abdominal cavity into the scrotum during human fetal development. sterility results if both testes fail to descend. in the case, the likely cause of sterility is that - ANS normal sperm do not develop at body temperature during the first three days of development, the human embryo obtains nutrients and energy from - ANS cytoplasm of the mother's egg hormone levels vary considerably over the course of pregnancy. which of the following hormonal changes does not play a role in the initiation of labour? Decreased progesterone increased oxytocin decreased prolactin increased relaxin - ANS decreased prolactin