Which one of the following animals is most likely to be a keystone species, based on the food web provided?
(1 point)
Odeer
O Mouse
frog
O grasshopper
The frog is most likely to be a keystone species in this food web. Keystone species play a critical role in maintaining the balance of an ecosystem and have a disproportionate effect on their environment compared to their abundance. In this food web, the removal of the frog could potentially have a significant impact on the populations of both primary consumers (grasshopper) and secondary consumers (snake).
Based on the data below, which group of animals are genetically diverse?
# of different type of species in the world
Birds
9,000+
Bears
8
Horses
350+
Whales
90
(1 point)
Obirds
O
bears
O whales
O horses
Birds are genetically diverse, as there are over 9,000 different types of bird species in the world. The greater the number of different species within a group, the greater the genetic diversity within that group. In contrast, bears, horses, and whales have much fewer species, making them less genetically diverse compared to birds.
The Northern Pacific seastar is a particularly successful invasive species. Which of the following explains why it is so successful in the waters of southeastern Australia, outside of its native environment? (1 point)
It can cling to the bottom of ships and other vessels.
â—Ž It breeds rapidly and has no predators in this environment.
â—Ž It consumes the eggs of the spotted handfish.
It is accustomed to a cold climate.
It
Ite
Ite
Iter
The correct explanation for the success of the Northern Pacific seastar in the waters of southeastern Australia is:
"It breeds rapidly and has no predators in this environment."
This indicates that the species is able to reproduce quickly and without any significant natural predators in the new environment, allowing its population to grow rapidly and outcompete native species.
Aside from killing native species, what other negative issue might an invasive species present? (1 point)
They might avoid interacting with her organisms.
They might provide economic benefit.
They might introduce other organisms, like viruses and bacteria.
They might increase the diversity of native species.
It
ite
The negative issue that an invasive species might present, aside from killing native species, is:
"They might introduce other organisms, like viruses and bacteria."
When an invasive species is introduced into a new ecosystem, they can bring along pathogens, viruses, bacteria, or parasites that can potentially harm or infect native species that may not have evolved defenses against them. This can have significant impacts on the health and stability of the ecosystem.
Your friend John is having trouble with his compost bin. The material in his compost pile doesn't seem to be decomposing well. You take a sample of the pile and check for the presence of microorganisms under the microscope. You see that there are indeed microorganisms; however, they don't appear to b*e_{3} growing very fast. John says that he regularly mixes his compost pile to expose it to oxygen but has noticed the pile feels cold. What is the most likely explanation for this problem? (1 point)
The compost pile contained incorrect amounts of "greens" and "browns".
The compost pile was placed in the sunshine.
The compost pile was sufficiently moist.
The compost pile contained aerobic bacteria..
The most likely explanation for the problem with John's compost pile is:
The compost pile contained incorrect amounts of "greens" and "browns".
The correct balance of "greens" (nitrogen-rich materials like grass clippings, kitchen scraps) and "browns" (carbon-rich materials like dry leaves, straw) is crucial for the success of a compost pile. If the balance is off, it can lead to slow decomposition and a cold pile. Mixing the compost pile and ensuring a proper balance of materials can help improve the decomposition process.
Plants, bison, elk, and wolves are all members of an ecosystem. The bison and elk are both primary consumers in this ecosystem, while the wolves are a predator. Over time, the bison completely disappear. Give an example of how the ecosystem may respond to this change, and explain how this relates to both resiliency and biodiversity. (4 points)
One potential response from the ecosystem to the disappearance of bison could be an increase in the population of elk, as they may now have less competition for resources. As the population of elk grows, they may graze more heavily on the vegetation in the ecosystem, leading to changes in plant composition and potentially affecting other species that rely on those plants for food or habitat.
This situation relates to both resiliency and biodiversity in the ecosystem. Resiliency refers to the ability of an ecosystem to resist disturbances and recover from changes over time. In this case, if the ecosystem is resilient, it may be able to adjust to the loss of bison by redistributing resources and populations among other species, such as the elk.
Biodiversity, on the other hand, refers to the variety of different species in an ecosystem. The disappearance of bison could impact biodiversity in several ways. If the ecosystem is not very biodiverse, the loss of one species like bison could have a more significant impact on the overall health and functioning of the ecosystem. However, if the ecosystem is more diverse, there may be other species, such as plants or smaller animals, that can compensate for the loss of bison and help maintain the balance of the ecosystem.
In summary, the disappearance of bison could lead to changes in population dynamics, resource availability, and species interactions in the ecosystem. The ability of the ecosystem to respond to this change and maintain its balance relates to its resiliency, while the impact on different species and overall biodiversity relates to the importance of having a diverse range of species in an ecosystem.