wsu biology 251 exam 2

the central nervous system (CNS) consists of?

a. the brain and spinal cord

dual innervation of organs by the autonomic nervous system (ANS) refers to the observation that?

b. both sympathetic and parasympathetic neurons innervates most organs, but usually have opposite effects on those organs

sympathetic preganglionic neurons release the neurotransmitter ...; sympathetic postganglionic neurons release the neurotransmitter ...

c. acetylcholine : norepinephrine

parasympathetic preganglionic neurons release the neurotransmitter ...; parasympathetic postganglionic neurons release the neurotransmitter ...

d. acetylcholine : acetylcholine

which of the following is innervated by sympathetic preganglionic neurons, that when activated, cause the release of epinephrine (adrenaline) into the blood?

b. adrenal medulla

true or false. for the somatic nervous system, a motor unit consists of a somatic motor neuron and all of the different skeletal muscle cells that is controls.

a. true

postganglionic neurons of the autonomic nervous system release their neurotransmitter from?

c. swellings along their axon terminals called varicosities

activation of which adrenergic receptor type usually has an inhibitory effect on the target cell?

b. beta2

which of the following physiological responses is associated with an elevation in parasympathetic nervous system activity?

b. decreased heart rate

which of the following is a type of acetylcholine (Ach) receptor, i.e., a type of cholinergic receptor?

e. both c and d are types of cholinergic receptors (nicotinic + muscarinic receptors)

the somatic nervous system regulates the activity of?

c. skeletal muscles

what is the correct order for the steps of synaptic transmission at the neuromuscular junction?

1. Ach binds to postsynaptic receptors on the muscle cell membrane.

2. Ach is released at the motor end plate.

3. a graded depolarization is produced on the muscle cell membrane.

4. an action potential is produced on the muscle cell membrane that is propagated over the cell and down the transverse tubules (t tubules).

5. ion channels that primarily allow diffusion of sodium into the muscle cell are opened.

6. voltage-dependent calcium channels on the somatic motor neuron axon terminal open.

7. an action potential arrives at the axon terminal of the somatic motor neuron.

c. 7,6,2,1,5,3,4

which of the following is the correct order of communication of visual information in the retina of the eye?

a. photoreceptor, bipolar cell, ganglion cell

this type of photoreceptor in the retina is used by the visual system to form low acuity images, i.e., they are NOT used to form high resolution images.

d. rods

in order to adapt to the dark when light decreases, the photoreceptors?

b. increase the amount of photopigment present in the cells

the smooth muscle responsible for changing the shape of the lens of the eye to allow it to focus near objects, i.e., accommodation, is controlled by which part of the nervous system?

d. parasympathetic nervous system

which of the following vision defects is INCORRECTLY matched with its cause?

b. astigmatism : discoloration of the lens

the inner circular layer of smooth muscle of the iris of the eye is innervated by the ... nervous system and its contraction causes ... of the pupil diameter.

a. parasympathetic : constriction

which of the following occurs during the focusing of light waves from near objects onto the retina, i.e., accommodation for near vision?

c. the lens becomes rounder, thus bending light waves to a greater extent to focus them onto the retina

sound waves traveling through the air first initiate a vibration of the ... the sound waves are then transmitted through the middle ear by the ...

d. tympanic membrane : ossicles

what is the primary function of the middle ear ossicles?

c. amplify sound waves as they are transmitted from the middle to the inner ear

in the inner ear, which cell type is used to transduce sound waves into action potentials in sensory neurons of the cochlear nerve?

e. hair cells

the sound sensitive cells in the cochlear duct (scala media) sit upon what membrane?

d. basilar membrane

what determines the "loudness" of a sound?

c. a greater degree of movement of the basilar movement in response to high amplitude sound waves passing through the cochlear duct (scala media)

the pitch (frequency) of sound is coded for by the?

a. information coming from hair cells on the portion of basilar membrane that is vibrating most in response to certain sound frequency

the area of the brain is often referred to as the "homeostatic control center" because it plays an important role in regulating homeostasis. it is involved in hunger, thirst, thermoregulation, and many other important homeostatic functions.

a. hypothalamus

damage to the cerebellum will lead to which of the following symptoms?

c. the generation of clumsy, poorly coordinated movements

what type of neural support (neuroglial) cell is necessary for normal development of the blood-brain barrier?

a. astrocytes

which area of the brain plays an important role in sleep-wake cycles, arousal of the cerebral cortex, and consciousness?

d. reticular formation of the brainstem

where in the central nervous system are the neurons that control many of the automatic physiological responses such as control of the cardiovascular system and respiratory system located?

a. brainstem

which of the following is specialization of the right side of the cerebral hemispheres in most individuals?

d. creativity and spatial perception

which of the following statements about the neuromuscular junction is FALSE?

e. each individual skeletal muscle cell receives several synapses from many different somatic motor neurons

true or false. the primary source of calcium for skeletal muscle contraction comes from the sarcoplasmic reticulum (SR) of the muscle cell.

a. true

what is the regulatory protein component of the thin myofilaments that binds to calcium, thereby initiating skeletal muscle contraction?

c. troponin

the shortening of a skeletal muscle cell during contraction involved which of the following?

d. the individual sarcomeres shortening

in skeletal muscle, the binding of calcium to troponin will directly allow which of the following?

c. the movement of tropomyosin, thereby exposing the myosin-binding sites on the thin myofilaments

which of the following best describes the interaction between transverse (T) tubules and the sarcoplasmic reticulum (SR) in skeletal muscle contraction?

b. action potentials in T tubules are detected by DHP receptors, which are coupled to ryanodine receptors in the sarcoplasmic reticulum and open channels for calcium release

in order for a skeletal muscle cell to relax, calcium is rapidly removed from the cytoplasm via?

a. calcium pumps (active transporters of calcium) that transport calcium back into the sarcoplasmic reticulum (SR)

true or false. skeletal muscle cells with the slowest myosin ATPase enzyme activity contract with the fastest velocity.

b. false

which of the following is not an accurate description of the specific skeletal muscle cell types?

d. slow oxidative cells are quick to fatigue