What type of blood vessel returns blood to the heart? a. artery b. vein c. capillary d. none of the above.

Which prevent errors in dna replication? a. helicase enzyme checks the dna for errors. b. each base can attach to only one other type of base. c. ribosome enzymes prevent errors from happening. d. dna contains no complementary base pairs.

As the human population grows, what happens to our natural-resource requirements? o they increase o they decrease o they do not change. they go in cycles

Which set of characteristics best describes sedimentary rock? a) largest type of rock, made of organic matter, hardest type of rock b) often contains layers, forms near sources of water, contains fossils c) least abundant type of rock, made of other rocks, made mostly of minerals d) most abundant type in earth's crust, made of magma/lava, contains no fossils