TLS Online TPP Program

#Question id: 5645


A reproductive difference between sea urchins and humans is ________.

#Unit 5. Developmental Biology
  1. the sea urchin egg completes meiosis prior to fertilization, but meiosis in humans is completed after fertilization

  2. sea urchin eggs and sperm are of equal size, but human eggs are much bigger than human sperm

  3. sea urchins, but not humans, have a need to block polyspermy, because only in sea urchins can there be more than one source of sperm to fertilize the eggs

  4. sea urchin zygotes get their mitochondria from the sperm, but human zygotes get their mitochondria from the egg

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TLS Online TPP Program

#Question id: 3285

#Unit 9. Evolution & Diversity of Life Forms

Natural selection continually operates on each species to keep up with improvements made by competing species; each species’ environment deteriorates as its competitors evolve new adaptations. This is known as

TLS Online TPP Program

#Question id: 3286

#Unit 9. Evolution & Diversity of Life Forms

 In a human population, the gene frequencies of the alleles for the ABO system are as follows:

A = 29%                         B = 7%                                    0=64%

Assuming complete random mating and Hardy-Weinberg equilibrium,

What are the blood type A frequencies in this population?

TLS Online TPP Program

#Question id: 3287

#Unit 9. Evolution & Diversity of Life Forms

Which statement is not an assumption of the Hardy–Weinberg law?

a. The allelic frequencies (p and q) are equal.

b. The population is randomly mating.

c. The population is large.

d. Locus is di-allelic

TLS Online TPP Program

#Question id: 3288

#Unit 9. Evolution & Diversity of Life Forms

Migration causes changes in the allelic frequency of a population by introducing alleles from other populations. The magnitude of change due to migration depends on

TLS Online TPP Program

#Question id: 3289

#Unit 9. Evolution & Diversity of Life Forms

If, someday, an archaean cell is discovered whose SSU-rRNA sequence is more similar to that of humans than the sequence of mouse SSU-rRNA is to that of humans, the best explanation for this apparent discrepancy would be

TLS Online TPP Program

#Question id: 3290

#Unit 9. Evolution & Diversity of Life Forms

Dog breeders maintain the purity of breeds by keeping dogs of different breeds apart when they are fertile. This kind of isolation is most similar to which of the following reproductive isolating mechanisms?