EXAM 3 Practice Questions (CH 9-11) - Dr. Jones

d

When examined under a microscope, in which type of muscle tissue are myofibrils not apparent? *remember striations

A. skeletal muscle

B.cardiac muscle

C.atrophied muscle

D.smooth muscle

a

The outermost layer of connective tissue surrounding a skeletal muscle is the

A. epimysium

B. perimysium

C. endomysium

D. sarcomysium

b

A muscle fascicle is surrounded by

A. epimysium

B. perimysium

C. endomysium

D. sarcomysium

a

The term aponeurosis refers to a

A. broad, flat, sheetlike tendon

B. band of connective tissue that encloses entire groups of tendons

C. connective tissue sheath that encloses several tendons

D. thickened part of a muscle

a

Which of the following links thin filaments to the sarcolemma?

A. dystrophin

B. myomesin

C. titin

D. myosin

c

Muscle contraction is triggered by impulses carried over

A. sensory neurons

B. afferent neurons

C. motor neurons

D. myofibrils

b

The motor end plate is part of a

A. motor neuron

B. skeletal muscle cell at the synapse

C. cardiac muscle cell at the intercalated disc

D. smooth muscle cell when two cells meet

a

Calcium ions move from the cytoplasm (sarcoplasm) into the sarcoplasmic reticulum because of the action of

A. active transport pumps in the sarcoplasmic reticulum membrane

B. ion diffusion channels in the sarcolemma

C. myosin binding sites in the sarcoplasmic reticulum membrane

D. acetylcholine receptors on the cell surface

a

When ATP attaches to the myosin head

A. the head detaches from actin

B. the head attaches to troponin

C. Ca2+ reacts with the ATP

D. actin and myosin both shorten

c

When calcium ion concentration in the sarcoplasm is low, the

A. myosin stretches and the muscle relaxes

B. actin detaches from the Z discs

C. troponin-tropomyosin complex slides back over the myosin binding sites

D. muscle cell membrane releases acetylcholine

b

The following is a list of events in random order that occur in the contraction of skeletal muscle.

Identify which of the subsequent letters represents the correct chronological order of these events.

1. Ca2+ binding to troponin

2. release of Ach at the neuromuscular junction

3. coming together of Z discs

4. depolarization of sarcolemma

5. myosin head attaching to myosin binding site on actin

6. depolarization of T-tubules

A. 1,5,2,4,3,6

B. 2,4,6,1,5,3

C. 2,6,4,5,1,3

D. 4,2,6,5,1,3

c

The binding of Ca2+ to __________________ starts the contraction cycle.

A. tropomyosin

B. ATP

C. troponin

D. sarcoplasmic reticulum

a

For the initiation of an action potential that starts contraction in skeletal muscle fiber:

A. Ach must bind to receptors on the motor end plate

B. Ach must bind to the neurolemma of the somatic neuron

C. acetylcholinesterase must break down Ach at the synapse

D. K+ must flow into the neurolemma

c

A motor neuron and all the muscle fibers it stimulates form a

A. motor end plate

B. neuromuscular junction

C. motor unit

D. muscle

a

In an isometric contraction

A. the muscle contracts but does not shorten

B. the muscle moves the bone to reduce the angle of a joint

C. the muscle increases in length during the contraction

D. no energy is expended because nothing moves

b

Which of the following does NOT have T-tubules?

A. skeletal muscle

B. smooth muscle

C. striated muscle

D. cardiac muscle

b

which nervous system is ganglia (group of neuron cell bodies) a part of?

a. CNS

b. PNS

a

The Nissl bodies function in

A. protein production

B. Ca++storage

C. insulation

D. Schwann cell production

b

Which type of neuroglial cells is found supporting neuronal cell bodies within ganglia?

A. astrocytes

B. satellite cells

C. ependymal cells

D. microglia

c

Retinal neurons are classified as

A. multipolar

B. unipolar

C. bipolar

D. pseudounipolar

d

Synaptic vesicles are found within the

A. Schwann cells

B. axon hillock

C. Nissl bodies

D. synaptic end-bulbs

c

Which of the following is not a function of neuroglial cells?

A. produce myelin sheath

B. participate in metabolism of neurotransmitters

C. generate action potentials

D. give support to neurons

c

Which of the following ions pass through the resting neuronal cell membrane most easily?

A. sodium

B. calcium

C. potassium

D. phosphate

d

During the absolute refractory period

A. protein anions are leaving the neuron

B. a very strong stimulus can generate a new action potential

C. neurotransmitters are being secreted

D. even a very strong stimulus cannot initiate a new action potential

b

In myelinated nerves, the

A. action potential occurs at a neurolemmocyte

B. action potential occurs at each node of Ranvier

C. action potential moves like a continuous wave across the cell membrane

D. threshold is lower than in unmyelinated nerves

d

A resting nerve fiber is polarized because the concentration of

A. Na+ and K+ ions is higher on the inside of the cell membrane

B. Na+ and K+ ions is higher outside the cell membrane

C. Na+ is higher on the inside and K+ is higher on the outside

D. Na+ is higher on the outside and K+ is higher on the inside

d

Saltatory conduction…

A. occurs only on unmyelinated fibers

B. occurs only if nodes of Ranvier are lacking

C. occurs only if the myelin sheath is continuous

D. occurs only on myelinated fibers

b

Which of the following is characteristic of unmyelinated fibers?

A. A fibers

B. continuous conduction

C. Schwann cells

D. saltatory conduction

b

A small deviation from the resting membrane potential that occurs because ligand-gated or mechanically-gated channels open or close is called

A. an action potential

B. a graded potential

C. a Section Reference 1ractory period

D. slow axonal transport

d

An inhibitory postsynaptic potential causes

A. depolarization

B. repolarization

C. EPSPs

D. hyperpolarization

d

Which of the following is NOT a class of small molecule neurotransmitters?

A. acetylcholine

B. biogenic amines

C. amino acids

D. neuropeptides

d

Which neurotransmitter class includes the neurotransmitters that enhance perception of pain and inhibit pain sensations?

A. acetylcholine

B. biogenic amines

C. amino acids

D. neuropeptides

c

Signs of multiple sclerosis usually begin

A. at birth

B. during the teen age years

C. between the ages of 20 and 40

D. usually in later life, around 60 years of age