Science Bowl

BIOLOGY

Biology - 22

BIOL-91; Multiple Choice:  Which of the following statements concerning platelets is
INCORRECT.  Platelets:

a)  contain DNA
b)  are roughly disk-shaped
c)  have little ability to synthesize proteins
d)  are between 1/2 and 1/3 the diameter of the red cell 

ANSWER:   A  --  contain DNA

BIOL-91; Short Answer:  What is the primary function of the platelets in huma blood?

ANSWER:   clotting   or   blocking leaks from blood vessels 

BIOL-91; Multiple Choice:  When a wound occurs in humans, the platelets in th blood activate a
substance which starts the clotting process.  The substance which starts the clotting is:

a)  adenosine (pron: ah-den-ah-seen)
b)  histamine
c)  lecithin

(pron: less-ah-thin)

d)  thrombin

ANSWER:   D  --  Thrombin

BIOL-91; Multiple Choice:  When looking at the cross section of the human tibia, one finds the
RED marrow in the:

a)  medullary cavity
b)  cancellous bone
c)  periosteum
d)  epiphysis

ANSWER:   A -- medullary cavity

BIOL-91; Multiple Choice:  Lengthening of long bones in humans occurs in a particular area of
the bone.  This area is called the:

a)  medullary canal
b)  cancellous bone
c)  periosteum

(pron: per-E-ahs-tee-em)

d)  epiphysis

(pron: eh-pif-eh-sis)

ANSWER:   D -- Epiphysis