The earth's systems are composed of 5 spheres. they include the atmosphere, cryosphere, hydrosphere, geosphere and the lower sphere hemisphere biosphere upper sphere

Hurry which of these is true about index fossils? a) are very scarcely found b) used as guides in relative dating c) found in the youngest layer of the rock d) used as reference points in absolute dating

Which of the following would be a body response when stepping outside without a coat on a snowy day? a. senaceous glands. secrete more senum b. more liquid is transported by the body to the skin fir insulation c. blood vessels in the skin narrow and contract d. blood vessels in the skin expand

Restriction enzymes are used in making recombinant dna. describe the role restriction enzymes perform when constructing recombinant dna.