What developmental landmark occurs at day 15 in humans?
a. primitive streak
b. neural tube
c. yolk sac
d. pharyngeal arches
e. somites
ANSWER: a
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A zombie apocalypse wipes out almost the entire human species before the zombie threat is eliminated. Only a group of 100 people who were at a family reunion on an uninhabited island survived. They returned to the mainland completely unaware of what had happened to everyone. Answer the following question(s) regarding the few survivors who now begin to rebuild the human population.Which of the following processes is most likely to occur on this small population of humans?
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a. present on the ocean floor b. present at the bottom of eutrophic lakes c. found in estuaries d. lack bacterial biofilms e. low salt content
If a human who is a tongue roller (T) and has unattached ear lobes (E) marries a person who cannot roll their tongue and has attached earlobes, could they produce an offspring that was also a non-tongue-roller with attached earlobes? What would be the genotype of the first parent? The second parent?
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