PLEASE HELP 12. Skates and rays have skeletons made of . 13. The series of dramatic changes in body form in an amphibian's life
cycle is called

What does natural resource management aim at ?

Which of these is true of the cytoplasm of an unfertilized egg? a. it is an unevenly distributed mixture of mrna, proteins, organelles, and other substances. b. it does not contain substances that are important in directing development. c. these substances are supplied by the sperm. d. it does not contain substances that are important in directing development. e. development is directed solely by the surrounding cells. f. it is a homogeneous mixture of mrna, proteins, organelles, and other substances. g. it does not contain substances that are important in directing development. h. these substances are produced by the dna of the fertilized zygote.

How did alexander fleming’s research solve a societal problem? he developed ways to treat inherited diseases. he advocated for regular hand washing to kill germs. he discovered a new type of medicine that could treat infections. he discovered the cause of mad cow disease, an emerging disease.