A. IS WHAT I WOULD CHOOSE
Pollution is always a good way to go but you don't have to do air pollution you can do water pollution or both air and water pollution.
Insects, arachnids, and crustaceans
Insects have 3 body segments. (head, thorax, abdomen)
Have a hard exoskeleton made of chitin.
Appendages be used for feeding, defense, sensory and reception.
Invertebrate phyla that obtains oxygen by using gills (marine) or air tubes (terrestrial.)
Use pincers and stingers as attack weapons to defend themselves
Characterized by having jointed legs, segmented bodies, and sometimes wings
Answer:
d
Explanation:
Fishes are aquatic vertebrates having scales, pharyngeal gill slits and paired fins. ... Most fish are ectothermic ("cold-blooded"), allowing their body temperatures to vary as ambient temperatures change. fishes have scales that covers the skin of fishes. Thus, the correct answer is option D.
Answer:
Why are embryos used in medical research?
Stem cells can be obtained at the early stages of embryo development; these cells are called human embryonic stem cells (hESC). They also could be used in research to develop drugs to treat serious diseases, or to repair organs following a stroke or heart attack.