BSC2085 LAB QUIZ 3

the terminal cisternae of the sarcoplasmic reticulum release calcium ions into the sarcoplasm

1

calcium ions bind to troponin, which pulls tropomyosin away from actin

2

the energy from ATP hydrolysis "cocks" the myosin head into an upright position

3

the myosin head binds to an actin subunit

4

a power stroke occurs as myosin moves into its relaxed position and pulls the thin filament toward the m line

5

ATP breaks the actin-myosin attachment, after which ATP is hydrolyzed and myosin is recocked

6

gray matter consists of a) cell bodies, dendrites, and unmyelinated axons b) myelinated axons c) unmyelinated axons d) myelinated cell bodies, dendrites, and axons

a

maximal tension in a skeletal muscle contraction is generated a) when the sarcomeres are at about 100 to 120 percent of their natural length b) when the muscle fiber is stretched before the contraction c) when the muscle fiber is shortened before the contraction, ans there is a maximal zone of overlap d) when the sarcoplasmic reticulum releases fewer calcium ions

a

where are synaptic vesicles located? a) axon terminals b) dendrites c) cell body d) both a and b are correct e) all of the above

a

which of the following muscles flexes the thigh at the hip? a) iliopsoas b) biceps femoris c) vastus intermedius d) gluteus medius

a

which of the following proteins make up a thick filament? a) myosin b) actin c) troponin d) tropomyosin e) choices b, c, and d are correct

a

which of the following spaces around the spinal cord is filled with cerebrospinal fluid (CSF)? a) epidural space b) subdural space c) subarachnoid space d) all of the above

a

excitation-contraction coupling refers to a) the action potential of a neuron triggering the release of neurotransmitters from synaptic vesicles b) the relationship between the length of the sarcomere and the tension generated c) the sliding of thick and thin filaments past one another d) the relationship between excitation at the sarcolemma and release of calcium ions from the terminal cisternae of the sarcoplasmic reticulum

d

what is the main action of the deltoid muscle? a) adduction of the arm at the shoulder joint b) retraction of the scapula c) depression of the scapula d) abduction of the arm at the shoulder joint

d

what triggers exocytosis of synaptic vesicles? a) arrival of a local potential at the cell body b) hyperpolarization of the postsynaptic membrane c) neurotransmitters binding to the postsynaptic membrane d) the influx of calcium ions into the axon terminal

d

what is a sarcomere?

the space from one z disc to the next

muscle primary function is to generate tension

all

neuroglial cells that anchor neurons and blood vessels, maintain extracellular environment around neurons, assist in the formation of the blood-brain barrier

astrocytes

the neuromuscular junction consists of three parts: (1) the ___ terminal, which contains synaptic vesicles with the neurotransmitter ___; (2) the ___; and (3) the ___

axon acetylcholine synaptic cleft motor end plate

a transverse (T) tubule a) stores sodium ions b) forms from inward extensions of the sarcolemma c) stores calcium ions d) is made of contractile proteins

b

the main function of an axon is to a) generate EPSPs or IPSPs when neurotransmitters bind their membranes b) generate and transmit signals in the form of action potentials c) function as the biosynthetic center of the neuron d) form the myelin sheath

b

what is the main action of the rectus abdominis muscle? a) rotation of the trunk b) flexion of the trunk c) extension of the trunk d) lateral flexion of the trunk

b

which of the following muscles extends the forearm at the elbow joint? a) brachioradialis b) triceps brachii c) biceps brachii d) brachialis

b

the neuron pictured is a a) pseudounipolar neuron b) bipolar neuron c) multipolar neuron d) unipolar neuron

c

muscle the calls are autorhythmic

cardiac some smooth

neurologlial ciliated cells in the CNS that form and circulate cerebrospinal fluid

ependymal cells

the spinal cord extends from the ___ of the occipital bone to the ___ vertebra. it terminates as the ___ and dives off a bundle of nerve roots called ___

foramen magnum 1st-2nd conus medullaris cauda

neuroglial phagocytic cells of the CNS

microglial cells

neuroglial cells that form the myelin sheath in the CNS

oligodendrocytes

difference between ESPS and ISPS

one opens na+ channels and depolarizes membrane and other open either k+ or cl- channels and hyperpolarize the membrane

how do a muscle's origin and insertion differ?

origin is the fixed attachment insertion moves with contradiction

neuroglial cells that surround the cell bodies of neurons in the PNS

satellite cells

neurologial cell that creates the myelin sheath in the PNS

schwann cells

muscle the cells are striated in appearance

skeletal cardiac

muscle the cells must be stimulated by a neuron to contract

skeletal some smooth

muscle the cells are multinucleate

skeletal some cardiac

muscle the cells lack striations and sarcomeres

smooth

muscle tissue lines hollow organs

smooth

muscle the cells are involuntary

smooth cardiac

muscle the cells are uninucleate

smooth some cardiac