TLS Online TPP Program

#Question id: 11537


Testosterone is an example of a chemical signal that affects the very cells that synthesize it, the neighboring cells in the testis, along with distant cells outside the gonads. Thus, testosterone is an example of ________.

 I) an autocrine signal

 II) a paracrine signal

 III) an endocrine signal

#Unit 7. System Physiology – Animal
  1. only I and II
  2. only II and III
  3. only I and III
  4. I, II, and III
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TLS Online TPP Program

#Question id: 12345

#Unit 10. Ecological Principles

Shannon's index of diversity is calculated using the equation below, where pi is the proportion of the ithShannon's index of diversity is calculated using the equation below, where pi is the proportion of the ith species and ln is natural logarithm. For a community with a given number of species, which of the following statements is true? species and ln is natural logarithm. For a community with a given number of species, which of the following statements is true?


TLS Online TPP Program

#Question id: 12346

#Unit 10. Ecological Principles

The schematic below shows the relationship between survivorship with age (relative to maximum lifespan) in Species 1 (dashed line) and Species 2 (solid line). Which of the following inferences is compatible with this figure?


TLS Online TPP Program

#Question id: 12347

#Unit 10. Ecological Principles

A team of conservation biologists, surveying a population of frogs on an island, captured and marked 312 individuals in the first sample. In a second sampling, 3 days later, the team caught 140 individuals of which 26 were previously marked. The total number of frogs on the island is estimated to be . (Use decimal notation, not fractions or percentage)

TLS Online TPP Program

#Question id: 12348

#Unit 10. Ecological Principles

The following equation represents a hypothetical relationship between fitness (w) and shoot: root ratio (r) in individuals of a plant species: w = 10r-10r2. At what value of shoot: root ratio (r), do these plants achieve maximum fitness? (Use decimal notation, not fractions or percentage)

TLS Online TPP Program

#Question id: 12349

#Unit 10. Ecological Principles

Males in a population differ in the time they spend displaying to females. A researcher hypothesizes that predators are responsible for these differences. Males display for longer durations when there are no predators in the vicinity and for shorter durations when there is a predator nearby. Which of the following study designs is the most appropriate test of this hypothesis?

TLS Online TPP Program

#Question id: 3296

#Unit 10. Ecological Principles

Some beetles and flies have antler-like structures on their heads, much like male deer. The existence of antlers in beetle, fly, and deer species with strong male-male competition is an example of