Chargaffs rules states that dna from any cell of all organisms should <span>have a 1:1 ratio (base Pair </span>Rule<span>) of pyrimidine and purine bases and, more specifically, that the amount of guanine is equal to cytosine and the amount of adenine is equal to thymine.</span>
Answer:
Place a glowing splint in the test tube, and if it reignites, it could be oxygen. Place a burning splint into a test tube, and if it goes out, it could be carbon dioxide. Or, place carbon dioxide gas in limewater, and if it turns milky and gets chunks, it is carbon dioxide.
The initial stages of human embryogenesis.
8-cell embryo, at 3 days.
Blastocyst with an inner cell mass and trophoblast.
Trophoblast differentiation.
Histogenesis of the three germ layers.
Artificially colored - gestational sac, yolk sac and embryo (measuring 3 mm at 5 weeks)
Embryo attached to placenta in amniotic cavity.
