There is a group of invertebrate animals called rotifers, among which a particular group of species reproduces, as far as is known, only asexually. These rotifers, however, have survived a long evolutionary history without evidence of having been overcome by excessive mutations.
Since the rotifers develop from eggs, but asexually, what can you predict?
A) The eggs and the zygotes are all haploid.B) The animals are all hermaphrodites.
C) While asexual, both males and females are found in nature.
D) All males can produce eggs.
E) No males can be found.
Answer: E
Assuming that the eggs are diploid, tetraploid, or partially tetraploid, what mechanism may still occur without fertilization?
A) meiosis in each generationB) meiosis in every second generation
C) independent assortment of maternal and paternal chromosomes
D) meiosis in times of adverse environmental conditions
E) crossing over of homologs
Answer: E
In these asexual rotifers, how does variation occur without meiosis and fertilization?
A) The rotifers have evolved a different mechanism to exchange DNA.B) Rotifers must produce haploid spores.
C) Variation is caused by mutation and maintained by selection.
D) Some rotifers must selectively lose chromosomes.
E) Rotifers must live only in specialized environments.
Answer: C
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