1.
If two species inhabit the same niche, one of the species will eventually die off as there is ____________ between organisms trying to survive with the same resources.
Correct Answer
L. Competition
Explanation
When two species occupy the same niche, they are competing for the same resources such as food, water, and shelter. This competition creates a struggle for survival, as there are limited resources available. Over time, the species that is better adapted to utilizing these resources will have a competitive advantage and will be more successful in reproducing and surviving. The other species, lacking these adaptations, will struggle to find enough resources to survive and eventually die off. Competition is therefore a key factor in determining which species will thrive in a given environment.
2.
The organism that does the killing of another is the:
Correct Answer
H. Predator
Explanation
A predator is an organism that kills and feeds on another organism. Predators have adaptations that allow them to catch and kill their prey, such as sharp teeth or claws, keen senses, and speed. They play an important role in maintaining the balance of ecosystems by controlling the population of their prey species. Natural selection is the process by which certain traits become more or less common in a population over time, and it can result in the evolution of adaptations that make predators more effective at killing their prey.
3.
The organism that is killed is the:
Correct Answer
B. Prey
Explanation
The correct answer is "Prey". In ecology, prey refers to the organism that is hunted and killed by another organism, known as the predator. This relationship is a fundamental aspect of the food chain and plays a crucial role in maintaining the balance of ecosystems. Prey species have various adaptations to help them avoid or defend against predators, such as camouflage, speed, or defensive mechanisms. Understanding the dynamics between predators and prey is essential in studying population dynamics and the overall functioning of ecosystems.
4.
The role of an organism in its habitat:
Correct Answer
A. Niche
Explanation
The role of an organism in its habitat is referred to as its niche. A niche includes the specific resources an organism uses, the way it interacts with other organisms, and its role in the ecosystem. It encompasses the organism's habitat, its food sources, its behavior, and its interactions with other species. The niche of an organism is important for its survival and reproduction, as it determines how the organism fits into the ecosystem and how it obtains the resources it needs.
5.
What is it when one organism kills another organism for food energy:
Correct Answer
E. Predation
Explanation
Predation refers to the act of one organism killing another organism for food energy. This relationship is characterized by a predator that hunts and kills its prey. The predator benefits from consuming the prey, while the prey is negatively affected by being killed. Predation is a common ecological interaction that helps regulate populations and maintain balance in ecosystems.
6.
Why are there fewer organisms at the top of the food chain?
Correct Answer
A. There are usually few organisms at the top because there is a limited amount of energy available at that level of a food web.
Explanation
The correct answer is that there are usually few organisms at the top because there is a limited amount of energy available at that level of a food web. This is because energy is lost as it moves up the food chain through processes such as respiration, digestion, and heat loss. As a result, there is less energy available to support a large number of organisms at the top of the food chain.
7.
All of the following are examples of limiting factors for populations except:
Correct Answer
C. Emigration
Explanation
Emigration is not a limiting factor for populations because it refers to the movement of individuals out of a population, which can actually help alleviate population pressure. Limiting factors are factors that restrict the growth or size of a population, such as limited space, food availability, and adverse weather conditions. These factors can lead to competition for resources, reduced reproductive success, and increased mortality rates, ultimately limiting population growth.
8.
An environmental factor that causes a population to decrease is a ____________.
Correct Answer
B. Limiting factor
Explanation
A limiting factor is an environmental factor that restricts the growth or size of a population. It can be any resource or condition that is in limited supply, such as food, water, space, or weather conditions. When these limiting factors become scarce or unfavorable, they can cause a decrease in the population by reducing birth rates, increasing death rates, or causing individuals to emigrate. Therefore, a limiting factor is an environmental factor that can cause a population to decrease.
9.
Changes in population may occur when a group moves into a population. This is called:
Correct Answer
M. Immigration
Explanation
Immigration refers to the movement of individuals into a population. It is one of the factors that can cause changes in population size. When individuals from a different group or population move into a specific population, it can result in an increase in the population size. This influx of new individuals can affect various aspects of the population dynamics, such as the birth rate, death rate, population density, and carrying capacity. Therefore, immigration is the correct answer in this context.
10.
If the death rate in a population is greater than the birth rate:
Correct Answer
A. The population will generally decrease.
Explanation
If the death rate in a population is greater than the birth rate, it means that more individuals are dying than being born. This leads to a decrease in the overall population size over time. As the number of deaths exceeds the number of births, the population will gradually decline.
11.
Identify this method of estimating populations:
Red wolves are tagged, released and checked systematically.
Correct Answer
L. Mark and recapture
Explanation
The method described in the question, where red wolves are tagged, released, and checked systematically, is known as mark and recapture. This method involves marking a sample of individuals, releasing them back into the population, and then recapturing a second sample at a later time. By comparing the number of marked individuals in the second sample to the total number of individuals, an estimate of the population size can be calculated.
12.
When might an ecologist use indirect observation to estimate a population?
Correct Answer
A. Indirect observation may be used when a population is small or difficult to find.
Explanation
An ecologist might use indirect observation to estimate a population when it is small or difficult to find. This method allows the ecologist to gather information about the population without directly observing or interacting with the individuals. It can be particularly useful in situations where the population is elusive, such as with rare or endangered species, or in remote areas that are hard to access. By using indirect observation techniques, the ecologist can still gather valuable data and make estimates about the population size and characteristics.
13.
What does the basic formula for mark and recapture mean?
Correct Answer
A. The population sample equals the number marked multiplied by the sum of the unmarked and recaptured divided by the number recaptured
Explanation
The basic formula for mark and recapture means that the population sample is equal to the number of marked individuals multiplied by the sum of the unmarked and recaptured individuals, divided by the number of recaptured individuals. This formula is used to estimate the size of a population by marking a certain number of individuals, releasing them back into the population, and then recapturing a sample of individuals later on. By comparing the number of marked individuals in the recaptured sample to the total number of individuals in the recaptured sample, an estimate of the population size can be calculated.
14.
One method of estimating population size is to count the number of organisms in a small area _________ and then apply multiples of that area to the larger area.
Correct Answer
P. Sample
Explanation
One method of estimating population size is to count the number of organisms in a small area as a sample and then apply multiples of that area to the larger area. This allows for a representative estimate of the population size without having to count every single organism in the entire area.
15.
A rabbit, possum and an owl are all members of the same:
Correct Answer
C. Community
Explanation
A community refers to a group of different species living in the same area and interacting with each other. In this case, the rabbit, possum, and owl are all different species, but they are living in the same area and are likely to interact with each other in some way. Therefore, they can be considered as members of the same community.
16.
All of the following are examples of limiting factors except:
Correct Answer
A. Time
Explanation
The given options all represent factors that can limit the growth or survival of a population. Time, however, is not a limiting factor in itself. It is a measure of duration or the progression of events, and does not directly restrict the resources or conditions available to a population. While time can indirectly influence factors such as food availability or weather patterns, it is not a limiting factor on its own.
17.
What is a sampling estimate?
Correct Answer
A. A sampling estimate is an approximation of a number based on reasonable assumptions.
Explanation
A sampling estimate is an approximation of a number based on reasonable assumptions. It is a method used to estimate a population parameter by taking a sample from the population and making inferences about the entire population based on the characteristics observed in the sample. This approach is commonly used when it is not feasible or practical to count or measure every individual in the population. By using statistical techniques, a sampling estimate provides a reliable and efficient way to estimate population parameters with a certain level of confidence.
18.
The number of individuals in an area of a specific size:
Correct Answer
G. Population density
Explanation
Population density refers to the number of individuals in a given area of a specific size. It is a measure of how crowded or dispersed a population is within a particular area. It is calculated by dividing the total population of an area by its land area. Population density helps in understanding the distribution and concentration of individuals within a population and is an important factor in studying ecology and understanding the dynamics of a population.
19.
When groups leave or are separated from their organism population to pursue a need, it is called:
Correct Answer
J. Emigration
Explanation
Emigration refers to the movement of individuals or groups out of a population or organism population to pursue a need. It is the opposite of immigration, which is the movement of individuals or groups into a population. Emigration can occur when there is a lack of resources, competition, or unfavorable conditions in the current habitat, prompting individuals or groups to leave in search of better opportunities elsewhere.
20.
Ecologists use the birth and death rates to calculate a population's growth rate, the rate the population is changing. The birth rate (b) minus the death rate (d) equals the growth rate (g). So, B-D=G
Based on this formula: a population of rabbits with an average of 760 births and 227 deaths has a growth rate of _________ per year:
Correct Answer
A. 533 rabbits
Explanation
The birth rate is given as 760 and the death rate is given as 227. To calculate the growth rate, we subtract the death rate from the birth rate: 760 - 227 = 533. Therefore, the growth rate of the rabbit population is 533 rabbits per year.
21.
Use the graph to answer the question about changes in the squirrel population.Over which time period(s) did the population increase?
Correct Answer
A. From 1994-1997
Explanation
The graph shows the squirrel population over time. The population starts at a low point in 1992, then increases steadily from 1994 to 1997. Therefore, the population increased from 1994-1997.
22.
Use the graph to answer the changes in squirrel population questions.
What was the size of the population the year the number of squirrels reached its lowest point?
Correct Answer
A. 200 squirrels
Explanation
The correct answer is 200 squirrels. This can be determined by looking at the graph and finding the point where the number of squirrels reaches its lowest point. At that point, the population size is 200 squirrels.
23.
Counting all the members of a ___________ is a method of __________________.
Correct Answer
A. Population and direct observation
Explanation
Counting all the members of a population is a method of directly observing the population. This involves physically counting or surveying every individual in the population to determine the total number. Direct observation allows for an accurate and comprehensive assessment of the population size, providing valuable data for various studies and research.
24.
Counting snake holes on the river bank is a _____________________ method of determining fiddler crabs populations.
Correct Answer
E. Indirect observation
Explanation
Indirect observation is a method of determining fiddler crab populations by counting snake holes on the river bank. This method involves inferring the population size based on indirect evidence, such as the presence of snake holes, which are known to be used by fiddler crabs. It is a practical approach when direct observation is not feasible or when the population is too large or spread out to be counted directly. By counting snake holes, researchers can estimate the population size and gather valuable information about fiddler crab populations.
25.
If the death rate in a population is greater than the birth rate:
Correct Answer
A. The population will generally decrease.
Explanation
If the death rate in a population is greater than the birth rate, it means that more individuals are dying than being born. This leads to a decrease in the overall population size over time. With fewer births and more deaths, the population cannot sustain itself and will gradually decline.
26.
Check the conditions that can limit the growth of a population:
Correct Answer
A. Temperature and rainfall
Explanation
Temperature and rainfall are two important factors that can limit the growth of a population. Both temperature and rainfall affect the availability of resources such as food and water, which are essential for the survival and reproduction of organisms. Extreme temperatures can be detrimental to the survival of many species, while inadequate or excessive rainfall can affect the availability of water and nutrients. Therefore, variations in temperature and rainfall can directly impact the population size and distribution of organisms in an ecosystem.
27.
Identify this method of estimating populations: Bottlenose dolphins are tagged, released and checked systematically.
Correct Answer
L. Mark and recapture
Explanation
The method of estimating populations described here involves tagging and releasing bottlenose dolphins and then systematically checking for recaptures. This technique is known as mark and recapture, where a sample of individuals is marked and released, and then a second sample is taken to determine the proportion of marked individuals. This proportion is used to estimate the total population size.
28.
What does a negative growth rate mean?
Correct Answer
A. The population is declining.
Explanation
A negative growth rate means that the population is declining. This indicates that the number of individuals in the population is decreasing over time. It implies that the death rate or emigration rate is higher than the birth rate or immigration rate, resulting in a decrease in population size.
29.
Which method would you use to determine the number of mushrooms growing on the floor of a large forest?
Correct Answer
A. Sampling
Explanation
Sampling would be the most appropriate method to determine the number of mushrooms growing on the floor of a large forest. This involves randomly selecting a smaller area or subset of the forest floor and counting the number of mushrooms within that area. By extrapolating the data from the sample to the entire forest floor, an estimate of the total number of mushrooms can be obtained. This method is efficient and practical for large areas, as it reduces the time and effort required to count every single mushroom.
30.
What is the difference between a species and a population?
Correct Answer
A. A species is a group of organisms that are pHysically similar and can mate with each other and produce offspring that can also mate and reproduce. A population is all the members of one species that live in a particular area.
Explanation
The correct answer explains that a species is a group of organisms that share physical similarities and have the ability to mate and produce offspring that can also reproduce. On the other hand, a population refers to all the individuals of a particular species that live in a specific geographical area. This explanation accurately distinguishes between the two terms, highlighting the criteria for defining a species and the scope of a population.