Science Bowl

BIOLOGY

Biology - 32

BIOL-91; Multiple Choice:  The phase of contraction of a muscle occurs when: 

a)  tropomyosin binds and releases actin
b)  myosin binds and releases actin
c)  actin binds and releases myosin
d)  none of the above

ANSWER:  B -- MYOSIN BINDS AND RELEASES ACTIN

BIOL-91; Multiple Choice:  Select the INCORRECT statement concerning the muscular system.

a)  Bones contact other bones at joints.
b)  Flexors decrease the angle of a joint.
c)  Adductors move a limb away from the midline.
d)  Tendons attach muscle to bone.

ANSWER:  C -- ADDUCTORS MOVE A LIMB AWAY FROM THE MIDLINE. 

BIOL-91; Multiple Choice:  Which type of muscle is a syncytium (pron: sin-sish-E-um)?

a)  skeletal
b)  cardiac
c)  smooth
d)  all of the above

ANSWER:  A -- SKELETAL

BIOL-91; Multiple Choice:  When the potential difference across a membrane of a neuron equals
the threshold, what results?

a)  movement of the membrane
b)  action potential
c)  relaxation
d)  contraction

ANSWER:  B -- ACTION POTENTIAL

BIOL-91; Multiple Choice:  What ions determine the resting potential of a nerve?

a)  sodium and calcium
b)  calcium and copper
c)  potassium and calcium
d)  sodium and potassium

ANSWER:  D -- SODIUM AND POTASSIUM