Q: Answer the following question given this paragraph: Predators play an important role in an ecosystem. For example, if they did not exist, then a single species could become dominant over others. Grazers on a grassland keep grass from growing out of control. Predators can be keystone species . These are species that can have a large effect on the balance of organisms in an ecosystem. For example, if all of the wolves are removed from a population, then the population of deer or rabbits may increase. If there are too many deer, then they may decrease the amount of plants or grasses in the ecosystem. Decreased levels of producers may then have a detrimental effect on the whole ecosystem. In this example, the wolves would be a keystone species. Q: What type of species have a large effect on the balance of organisms in an ecosystem? A:

OPTIONS:
- decomposers
- producers
- secondary consumers
- keystone

A: keystone

input: OPTIONS:
- density
- size
- weight
- shape Now, answer this question: Answer the following question given this paragraph: Cells come in many different shapes. Cells with different functions often have different shapes. Q: Cells with different functions often differ in what physical property? A:
A:
output: shape

Answer the following question given this paragraph: Geologists say that the Grand Canyon ( Figure above ) has "layer cake geology. " This is because the rock strata are in layers. They are extremely easy to see. Sedimentary rocks are like a book that tells the story of the environment in which they formed. Rock units can be traced across large expanses. Looking down into the Grand Canyon, you get a sense of the vastness of space and of time. Q: What is stacked in layers in "layer cake geology"? A:

OPTIONS:
- sediment
- soil
- horizontal stata
- rock stata

Answer: rock stata

Problem: OPTIONS:
- elasticity
- malleability
- viscosity
- tensile strength
Q: Answer the following question given this paragraph: makes it clear that the deformation is proportional to the applied force. Figure 5.13 shows the Hooke's law relationship between the extension L of a spring or of a human bone. For metals or springs, the straight line region in which Hooke's law pertains is much larger. Bones are brittle and the elastic region is small and the fracture abrupt. Eventually a large enough stress to the material will cause it to break or fracture. Tensile strength is the breaking stress that will cause permanent deformation or fracture of a material. Hooke's Law. Q: What term refers to the breaking stress that will cause permanent deformation or fracture of a material? A:
Answer: tensile strength

Problem:OPTIONS:
- cell structure
- ribosomes
- cell density
- sex chromosomes

Answer the following question given this paragraph: Sex chromosomes determine sex in animals and many plants. Other chromosomes are called autosomes. Sex-linked traits are controlled by genes on sex chromosomes. They may be inherited differently than autosomal traits. Q: What determines sex in animals? A:
****
A: sex chromosomes

Problem:OPTIONS:
- temperature charges
- capacitance
- surface flow
- electrical charges

Answer the following question given this paragraph: In physics, resistance is opposition to the flow of electric charges in an electric current as it travels through matter. The SI unit for resistance is the ohm. Resistance occurs because moving electrons in current bump into atoms of matter. Resistance reduces the amount of electrical energy that is transferred through matter. That's because some of the electrical energy is absorbed by the atoms and changed to other forms of energy, such as heat. You can see an animation of resistance at the level of atoms and electrons at this URL: http://www. physics. org/explorelink. asp?id=1738&q=electricalresistance&currentpage=1&age=0&knowledge=0&item=3. Q: In physics, resistance is opposition to the flow of what? A:
****
A:
electrical charges