Question

1. a salt marsh food web shows how energy and matter are transferred in an ecosystem. which will most likely occur if the number of grasshoppers decreases? a. the northern harrier population will increase. b. the lizard population will increase. c. the cordgrass population will decrease. d. the killdeer population will decrease. 2. which best explains the genetic similarities between species? a. more closely related species will have identical dna. b. more closely related species will have fewer dna similarities. c. more closely related species will have more similarities in dna. d. there is no link between the relationships of species and their dna. 3. what will most likely happen if a nonnative species is introduced into a stable ecosystem? a. the native species will change their diet, and the ecosystem will remain stable. b. the native species will move to another area, and the ecosystem will remain stable. c. the native species will have to compete for resources with the nonnative species, and the ecosystem will become unbalanced. d. the native species will share their food with the introduced species, and the ecosystem will become unbalanced. 4. how does a population experience variation in traits? a. through an increased birth rate b. through a decreased death rate c. through mutations and genetic recombination d. through the introduction of an invasive species 5. wind - generated electrical energy produces no emissions and is generally an environmentally clean technology. which statement best explains a disadvantage of wind turbines? a. wind turbines can adversely impact migratory birds. b. wind turbines can be constructed in any environment. c. wind turbines remove large amounts of thermal energy from the habitat. d. wind turbines distribute wind energy over growing crop plants. (and there is an incomplete question at the end: what is the main goal of the human genome project? what bene...)

Explanation:

1. For question 1: Grasshoppers are prey for lizards and killdeers. A decrease in grasshoppers reduces food for killdeers, so their population will drop. a is wrong because harriers lose food sources, b is wrong as lizards lose prey, c is wrong as cordgrass loses a herbivore so it will increase.
2. For question 2: Genetic similarity correlates with evolutionary relatedness; closer species share more DNA sequences. a is wrong because no two species have identical DNA, b is wrong as it reverses the relationship, d is wrong as there is a clear link.
3. For question 3: Nonnative invasive species outcompete native species for limited resources, breaking the stable ecosystem balance. a and b are wrong because native species cannot easily adapt or move to maintain stability, d is wrong as native species do not willingly share food resources.
4. For question 4: Mutations create new genetic variants and genetic recombination during sexual reproduction reshuffles existing alleles to create trait variation in populations. a and b only change population size, not trait variation, d only introduces outside traits rather than creating inherent variation.
5. For question 5: Wind turbine blades pose a collision risk for migratory birds, which is a well-documented environmental disadvantage. b is an advantage/incorrect as turbines cannot be built everywhere, c and d are factually incorrect statements about wind turbine impacts.

Answer:

1. d. The killdeer population will decrease.
2. c. More closely related species will have more similarities in DNA.
3. c. The native species will have to compete for resources with the nonnative species, and the ecosystem will become unbalanced.
4. c. through mutations and genetic recombination
5. a. Wind turbines can adversely impact migratory birds.