An example of keystone species are ____
a. beavers that build dams
b. mice that feed on mushrooms and truffles
c. Douglas fir trees
d. kudzu
e. earthworms that aid decomposition
ANSWER: a
You might also like to view...
Which group of plants contains the tallest and oldest trees on Earth?
A. cycads B. ginkos C. conifers D. gnetophytes E. angiosperms
An enzyme that adds phosphate groups to proteins is called a phosphatase
1.True 2.False
Predict the experimental outcome if Hershey and Chase had used a bacterial cell instead of a bacteriophage in the procedure.
A. Radioactivity would be detected in neither the supernatant nor the pellet. B. Radioactivity would be detected in the supernatant but not in the pellet. C. Radioactivity would be detected in the pellet but not in the supernatant. D. Radioactivity would be detected in both the supernatant and pellet.
Most bird species that form flocks show a negative relationship between flock size and individual vigilance (i.e., the larger the flock, the less often an individual lifts its head to scan the surrounding environment). However, some bird species have shown a positive relationship between flock size and individual vigilance. The positive relationship is particularly strong when flocks are space-constrained, such as in small ponds or fields. What is the most likely explanation for this?
A. As flock size increases, the number of "cheaters" increases, so individuals must spend more time scanning for predators. B. As flock size increases, the risk for interference and aggression between members increases, so individuals must scan for both conspecifics and predators. C. As flock size increases, the risk of predation for any given member increases, so individuals must spend more time scanning for predators. D. As flock size increases, mating opportunities decrease, so individuals must spend more time scanning for potential mates.