Activities Quiz
1.

The _____ is the region of the eye where photoreceptors are most highly concentrated. (Activity 49A)

lens
fovea
optic nerve
pupil
sclera


2.

What name is given to the tough layer that forms the "white" of the eye? (Activity 49A)

blind spot
choroid
fovea
sclera
aqueous humor


3.

The _____ changes shape to focus light on the retina. (Activity 49A)

vitreous humor
blind spot
cornea
lens
optic nerve


4.

What name is given to the opening that allows light into the interior of the eye? (Activity 49A)

sclera
pupil
ligament
optic nerve
retina


5.

Which of these is a component of a human's appendicular skeleton? (Activity 49B)

ribs
sternum
femur
skull
vertebral column


6.

What type of joint allows you to open and close your mouth? (Activity 49B)

ball and socket
hinge
pivot
saddle
none of the above


7.

What type of joint allows you to shake your head "no"? (Activity 49B)

ball and socket
hinge
pivot
saddle
none of the above


8.

What type of joint is found where the humerus joins the shoulder blade? (Activity 49B)

ball and socket
hinge
pivot
saddle
none of the above


9.

The thick filaments of sarcomeres are composed of _____. (Activity 49C)

myofibrils
actin
motor neurons
myosin
Z lines


10.

The thin filaments of sarcomeres are composed of _____. (Activity 49C)

myofibrils
actin
motor neurons
myosin
Z lines


11.

A single muscle cell is referred to as a _____. (Activity 49C)

myofibril
muscle fiber
muscle neurons
sarcolemma
sarcomere


12.

During the course of muscle contraction the potential energy stored in ATP is transferred to potential energy stored in _____. (Activity 49D)

the myosin head
the myosin tail
the thin filament
actin
the Z line


13.

The release of _____ ions from the sarcoplasmic reticulum is required for skeletal muscle contraction. (Activity 49D)

sodium
phosphate
potassium
chloride
calcium


14.

Myosin heads bind to _____, which they then pull and cause to slide toward the center of the sarcomere. (Activity 49D)

thin filaments
Z lines
sarcomeres
myofibrils
thick filaments


15.

Of these events, the first to occur when a motor neuron stops sending an impulse to a muscle is _____. (Activity 49D)

the pumping of calcium ions out of the cytoplasm and back into the sarcoplasmic reticulum
the release of myosin heads from the thin filament
thin filaments slide back to their relaxed positions
proteins on the thin filaments block actin's myosin-binding sites
all of these events occur simultaneously



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2002 Pearson Education, Inc.,
publishing as Benjamin Cummings