In a human body, which of the following represents the highest level of structural organization?
a an atom in the lung.
b lung tissue
c the lungs
d the respiratory stystem

Which of the following is a consequence of urban heat islands? increased precipitation downwind of the city? increased precipitation upwind of the city? decreased winds within the city? increased winds within the city?

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?

Step 1 review the imaginary strand of dna below. note the complementary base pairs. a g c a a t c c g t c t t g g t c g t t a g g c a g a a c c step 2 to begin replicating this strand of dna, draw the two sides of the strand separating. step 3 now, draw the free-floating bases linking up with the separate sides. remember to follow the rules of complementary base pairing. step 4 draw the two resulting dna strands.