All multicellular organisms begin as a skin cell. within four or five days, that first cell multiplies into a ball-like structure of about 100 cells. what is this structure called? a. blastocyst b. blood c. placenta d. heart

If a human has 23 pairs of chromosomes in every muscle cell of its body how many chromosomes will be in a human egg or sperm

According to the rna world hypothesis, rna acted as the genetic material and catalyzed reactions in ancient cells. what conclusion can you draw from this?               a.  this implies that dna and proteins aren't essential in cells today.    b.  this implies that rna can catalyze any chemical reaction that enzymes catalyze.    c.  this implies that if a cell has a problem with its dna, its rna can compensate for the damaged dna.    d.  this implies that dna and proteins evolved after rna.

Biology students used raw eggs in an experiment on tonicity and osmosis. the students put their eggs into vinegar to remove the shells. the vinegar was used to remove the shell from the raw egg. what other effect(s) did the vinegar have on the egg?