Biology Questions

The connection of the yolk sac to the embryo diminishes during folding until it is the narrow, endoderm-lined vitelline duct, which is located at the umbilicus and opens into the ileum and the yolk sac

The yolk sac is a large, endoderm-lined cavity lying ventral to the developing embryo

Based on naïve assumptions, we might expect that optimal life history would be to never die and to produce an infinite number of offspring. Why can such a life history never evolve?

The data on a prezygotic isolation below were taken from the study we discussed in class that concluded that species tended to evolve complete reproduction isolation after 1 million years of seperation (or 1 unit of genetic distance,D). Which of the following is a valid conclusion based on these data?

Which amino acids are modified by Methylation?

Sexual Selection tends to be strongest in ----- mating systems, which tend to have the highest -----?

In a completely monogamous species where males and females have equal variance in reproductive success, the trivers - Willard hypothesis would predict that females in better condition should produce:

In addition to ecological differences that lead to the disruptive selection, that factor is crucial in order for sympatric speciation to occur?

Populations of snails with higher parasite prevalence also tend to have more males. What does this pattern suggeswt?

The following graphs show data on lifetime mating success in wattled jacanas. Based on what you know about this species, which graph plots data from females?

In an experiment by reznick and colleague, guppies that were placed in a lower predation streams evolved later reproduction an produced fewer, larger offspring. This illustrates that:

Which of the following does not represent a possible direct benefit of mate choice?

Chimpanzees have larger testes for their body weight than gorillas. What is the best explanation for the pattern?

Hamiltons rule for the evolution of altruism states that altruism may increase in a population when:

In a species, if beetle with an intense male-male competition before mating, which of these sexually selected traits would be most likely to evolve?

Female sticklebacks prefer males with brighter red coloration on their belly. Given the results depicted in the graph below, it appears that females that choose redder males benefit from:

An experiment showed that flycatchers are more likely to help their neighbors mob a potential predator when?

Which amino acids are modified by Acetylation?

Which types of species interaction often leads to the addition of new species, which increases the benefit ( and decreases the cost) for other species involved.

Imagine an interaction between an insect and a plant. The insect eats the plant's pollen but manages to transfer some of it to other flowers in the population. How would you classify this interaction?