Quizzes 3

Increasing muscle mass thru exercise is primarily due to...
Correct!

increasing the thickness of existing muscle fibers.

An olympic sprinter will tend to have more thicker muscle fibers relying on glycolytic metabolism.

True

Smooth muscle is under voluntary control.

False

Reflex arcs are an exception to the rule that skeletal muscle is always under voluntary control.

True

During voluntary movement, you change your body posture....

before you move in anticipation of the movement AND after initiating the movement to compensate or correct your body's position.

The calcium pumps (Ca2+ ATPase) in the sarcoplasmic reticulum are examples of...

active transport

The muscle twitch (i.e. the contraction-relaxation cycle) is much faster than an action potential.

False

Release of acetylcholine at the neuromuscular junction typically results in...

opening of chemically-gated sodium channels.
opening of voltage-gated sodium channels.
release of calcium ions (Ca2+) from the sarcoplasmic reticulum.

Motor neurons typically control multiple muscles cells.

True

In skeletal muscle cells, incoming electrical signals travel through the...

T-tubules

The structural elements responsible for the striated appearance of skeletal muscle are called...

sarcomeres

The inner ear houses two fluid filled structures. Which of these is critical to equilibrium?

semicircular canals

What features are shared (or similar) between hearing and vision?

pathways from paired sensory organs diverge and cross over on the way to the CNS
information is relayed thru the thalamus
they both involve some type of tonic receptor

The lens bends light and focuses it onto the...

fovea

The primary sensory neurons in your retina are depolarized, the concentration of cyclicGMP in your rods is high, and cyclic-nucleotide gated channels are open. It is likely..

night time

Which of these is most likely an example of top-down processing in the visual system?

an optical illusion

The sensory system does all of the following EXCEPT...

projects nerves and signals to effect change in target muscles

The sensory system does all of the following:

encode information from the environment
relay information about the environment to the CNS
detect change in the environment

Which of these is NOT a characteristic of olfaction?

Olfaction is one of the three senses contributing to our sense of equilibrium.

Characteristics of the olfaction

Neurons from the olfactory bulb interact with the amygdala and hippocampus.
Olfactory neurons die and are replaced by new neurons roughly every 2 months.
The olfactory tracts do not directly relay to the CNS via the thalamus.

The taste receptor cells are NOT neurons.

True

A person with defective rods will have trouble...

seeing well in the dark.
distinguishing shapes at the periphery of the visual field.

A blind spot in the retina occurs where...

the optic nerve leaves the eye.

iris

controls diameter of pupil

rhodopsin

light receptor

tectorial membrane

stimulates hair cells

cristae in ampullae

sense rotational movement

otoliths in maculae

sense lateral movement

The primary purpose of the middle ear bony structures (maleus, incus and stapes) is to...

amplify the vibration as it conducts to the cochlea.

You work at the Tabasco factory in Louisiana. You spend your workday blending barrels of fermented chili peppers with vinegar and bottling hot sauce. The smells do not bother you, because...

Olfactory receptors are phasic, they quickly adapt to constant stimulus.

Skeletal muscle contraction starts when the muscle fiber depolarizes due to the release of calcium into the cytoplasm.

False

Why does rigor mortis occur after death?

There is no ATP available to bind to myosin.
Myosin is tightly bound to actin.

Which is a potential energy source for an athlete sprinting the 40-yard dash?

phosphocreatine

Which about smooth muscle contraction is FALSE?

Troponin plays the same role as in skeletal muscle.

As a protective mechanism, stretching a skeletal muscle fiber causes sensory neurons to ______ their rate of firing.

increase

_______ receive blood from outside of the heart, while ______ receive blood from within the heart.

atria, ventricles

Match the cardiac muscle cell feature to its function:

desmosome - keep cells linked

gap junctions - allow signals to quickly pass

autorythmia - self-generated action potentials

When the membrane potential of autorhythmic cells reaches threshold (-40 mV), it triggers...

the opening of voltage-gated Ca++ channels.

Cardiac contractile cells have relatively short, straight T-tubules compared to other muscle cell types.

false

Arterioles do NOT have any connective tissue.

false

Exchange of cellular products primarily occurs at the..

capillaries

Which of the following would you expect to be true?

Tissues with high metabolic activity have dense capillary networks.

smooth muscle contraction requires Ca2+ to enter from outside the cell

False

during voluntary movement you change your body posture..

both in anticipation of the movement and after initiating move

smooth muscles are activated when…

signals fromautonomic neurons bind chemically-gated channels

stretch receptors open mechanically gated channels

intracellular regulatory signals open “store activated” channels

which statement is true abt skeletal muscle contraraction

z-discs move closer to eachother

age related sensorineural hearing loss commonly presents as the inability to hear high pitch sounds

true