#### 题目列表

While marine hermit crabs are well known for being omnivorous filter feeders, less is known about the role they may play as active camion scavengers in intertidal ecosystems. Prior studies have revealed that intertidal hermit crabs can be attracted to chemical cues from gastropods(snails) killed by predators. Yet their attraction is usually assumed to be driven primarily by the availability of new shells for shelters rather than by food. Researchers conducted field experiments to assess hermit crabs` potential role as generalist carrion scavengers on the California coast, examining their speed of attraction and the size of the aggregations they formed in response to chemical cues from freshly smashed gastropods and mussels both of which indicated available carrion. Compared to all other marine species, hermit crabs were the fastest to arrive at the provisioning sites. Hermit crabs also dominated the provisioning sites, accumulating in the largest numbers, with aggregations of up to 20 individuals, which outcompeted all other scavengers for carrion. Notably, hermit crabs arrived equally quickly for both smashed gastropod and mussel, even though the latter does not offer suitable shells for hermit crabs and even though the former only yields shell-related chemical cues over time frames longer than the experiments. These results thus suggest that shell availability is not the only, or even the primary reason marine intertidal hermit crabs aggregate at carrion sites; they also aggregate to forage, thereby playing an important role as active carrion scavengers in intertidal ecosystems.
The highlighted sentence primarily serves to
It can be inferred from the passage that the findings from the "field experiments "shed new light on which of the following issues related to hermit crabs?
Which of the following can be inferred from the passage about gastropod carrion?
Sensationalism--the purveyance of emotionally charged content focused mainly on violent crime, to a broad public--has often been decried, but the full history of the phenomenon has yet to be written. Scholars have tended to dismiss sensationalism as unworthy of serious study, based on two pervasive though somewhat incompatible assumptions: first, that sensationalism is essentially a commercial product, built on the exploitation of modern mass media, and second, that it appeals almost entirely to a simple, basic emotion and thus has little history apart from the changing technological means of spreading it. An exploration of sensationalism early history, however, challenges both assumptions and suggests that they have tended to obscure the complexity and historicity of the genre.
According to the passage, scholars have not given sensationalism serious consideration because they believe sensationalism
In the context in which it appears, "charged" most nearly means
Calculating hydroelectric plants' environmental impact is not simple. Dam building requires steel and cement, the manufacture of which entails greenhouse gas emissions. Estimates for these emissions are relatively straightforward to make and show that the consequences are small compared to the benefits of generating greenhouse gas-free hydroelectric power. But more difficult-to-estimate greenhouse gas contributions occur during the plants operation. The submerging of large areas behind dams results in the microbial decomposition of vegetation, which produces substantial quantities of methane-a potent greenhouse gas. Furthermore, eradicating vegetation eliminates the consumption of the greenhouse gas CO2 by that vegetation. Estimating amounts of these gases is difficult, and amounts vary depending upon the specific location, terrain, and power intensity of the dam with its associated lake.
The author would most likely agree with which of the following assertions about the environmental impact of hydroelectric power plants?
The highlighted sentence serves primarily to

In the xy-plane, the equation of line RS is y = x - 3

Quantity A: The area of triangular region RST

Quantity B:40
x and y are prime numbers

x+y is odd

Quantity A: x

Quantity B:3
When the total cost of 90 dollars for the rental of a van was evenly divided among n passengers, the cost to each passenger was less than 23 dollars.

Quantity A: n

Quantity B:5
Quantity A:$\frac{1}{5}$ percent of 59

Quantity B:0.2
(x-3)(x+3)=(2x-1)

Quantity A: x

Quantity B:2
On the number line, P is a point between -3 and -2, Q is a point between -1 and 0, and R is a point between 0 and 1.

#### Quantity A

The distance between P and Q

#### Quantity B

The distance between Q and R

The function f is defined for all numbers x by f(x)=57x2-kx+925, where k is a constant, and f(x)=f(-x) for all x.

Quantity A: k

Quantity B:0
A box manufacturer is designing a closed box in the shape of a rectangular solid. The ratio of the lengths of the sides of the box is 1 to 2 to 3. The total surface area of the box is 550 square inches. What is the volume of the box, in cubic inches?

In square MNOP shown, the two shaded square regions have areas in the ratio 9 to 1. If square region MNOP has area 144, what is the area of each of the two unshaded rectangular regions?

The circle in the xy-plane shown has radius 5 and center O. Line l has a slope of $\frac{1}{2}$ and passes through the center of the circle. P is the point in the first quadrant at which l intersects the circle. Which of the following represents the coordinates of point P?

25000 +道题目

137本备考书籍