A tracer is a substance with what attached to it?
a. a radioisotope
b. water
c. glucose
d. ion
e. antibodies
ANSWER: a
You might also like to view...
During HIV reproduction, spike glycoproteins
A. do not enter the cell with the virus. B. are released into the cytoplasm by cellular enzymes. C. are embedded in the infected cell membrane. D. are assembled into the virus along with reverse transcriptase. E. are embedded in the viral capsid.
Fish move water in only one direction over their gills, permitting countercurrent flow.
Answer the following statement true (T) or false (F)
A man with a dirty cut on his hand appears at the emergency department for treatment. In order to clean the wound, the health-care provider should use
A) a solution of very low pH. B) a solution of sterilized tap water. C) a weak (low concentration) solution of salt water. D) distilled water.
Birds and insects both have wings, but we do not consider this similarity as evidence of relatedness because
A. the wings are not homologous structures with a common ancestral origin. B. bird wings, but not insect wings, function on the physics principles of lift. C. there is no fossil link between these groups. D. birds and insects did not evolve in the same region or live at the same time period. E. insect wings are vestigial.