Which structure in bird and mammalian embryos functions like the blastopore of frog embryos?
A) primitive streak
B) neural plate
C) archenteron
D) notochord
E) somites
Answer: A) primitive streak
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What genetic information is indicated by describing a person as having hemophilia?
A) genotype B) phenotype C) genetic code D) number of chromosomes
Which of the following is a reason to question the sustainability of ethanol production from corn?
A. Gas mileage is better with ethanol than gasoline B. Only waste materials from corn production are used to make ethanol, so it doesn't compete with food production. C. Ethanol burns cleaner than gasoline. D. Farmers use a lot of fossil fuels to grow the corn used to make ethanol. E. Conventional agriculture uses less energy and increases the EROI of corn ethanol.
What are the major differences between LTR and non-LTR retrotransposons?
What will be an ideal response?
Two species that have experienced several thousand years of isolation from one another are now incapable of producing viable offspring despite mating efforts. What type of reproductive isolating mechanism developed between the two species?
What will be an ideal response?