Please help me with this east question asap What are the features of Class Demospongiae?
A. small and dull in color with a skeleton make of calcium
carbonate
B. can be up to 6 ft. in length and used as natural bath sponges
C. "glass sponges" made from silica

Please only respond if you know the answer

c.) polymerase chain reaction

- "unlike the original dna fingerprinting method, dna profiling does not use restriction enzymes to cut the dna. instead it uses the polymerase chain reaction (pcr)? to produce many copies of specific str sequences. pcr is an automated procedure that generates lots of copies of a specific sequence of dna."

hey bro i looked it up on google the structure of the eye-spot in euglena viridie, e. ehrenbergii, and phacus pyriyorme is not as franzé haa described it. the so-called “crystal body” and “lens bodies” were not found in any of the individuals of the species examined by me. as earlier observers have stated, the eye-spot consists simply of a mass of pigment granules arranged in a single layer, and probably embedded in a protoplasmic framework, but the latter could not be seen, and its presence was only inferred from the fact that the pigment granules must be held together in some way, thd the eye-spot as a whole is capable of expansion, and that the pigment granules can be separated from each other.

hope this   and an i get brainlsiest

wegner's theory did not explain how the continents could move

explanation: