2) Bones are classified by whether they are weight-bearing or protective in function. 2) F
3) The trabeculae of spongy bone are oriented toward lines of stress. 3) F
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
4) The cell responsible for secreting the matrix of bone is the:
A) osteoblast.
5) What kind of tissue is the forerunner of long bones in the embryo?
C) hyaline cartilage
6) The most abundant skeletal cartilage type is:
B) hyaline.
7) The periosteum is secured to the underlying bone by dense connective tissue called:
A) Sharpey's fibers.
8) Which hormone increases osteoclast activity to release more calcium ions into the 8) bloodstream?
A) parathyroid hormone
9) Vertebrae are considered ________ bones.
B) irregular
TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false.
10) The thin filaments (actin) contain a polypeptide subunit G actin that seems to have no function. 10) F
11) The force of muscle contraction is controlled by multiple motor unit summation or recruitment. 11) T
12) A contraction in which the muscle does not shorten but its tension increases is called isometric. 12) T
13) Muscle contraction will always promote movement of body parts regardless of how they are attached. 13) F
14) The effect of the neurotransmitter on the muscle cell membrane is to modify its permeability properties temporarily. 14) T
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
15) Calcium ions bind to the ________ molecule in skeletal muscle cells. B) troponin
16) Myoglobin: D) holds a reserve supply of oxygen in muscle cells.
17) Which of the following are composed of myosin? C)