1.
All of the following are examples of limiting factors for population except:
Correct Answer
C. Emigration
Explanation
Emigration refers to the movement of individuals out of a population. It is not a limiting factor for population because it does not directly affect the population size or growth. In fact, emigration can help relieve population pressure by reducing competition for resources. On the other hand, factors like space, food, and weather can limit population growth as they determine the carrying capacity of an environment and the availability of resources necessary for survival and reproduction.
2.
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 include factors such as availability of food, space, water, or other resources necessary for survival and reproduction. When these resources become limited, it can lead to a decrease in the population size as individuals struggle to survive and reproduce. Therefore, a limiting factor can cause a population to decrease.
3.
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. Therefore, the growth rate can be calculated by subtracting the death rate from the birth rate: 760 - 227 = 533. This means that the population of rabbits is growing by 533 rabbits per year.
4.
Changes in the 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. When new individuals join a population, it can lead to changes in the population size and composition. Immigration is an important factor in population dynamics and can affect various ecological processes such as competition, predation, and resource availability.
5.
Use the graph to answer the questions about the changes in the squirrel population.
Which year did the squirrel population decrease the most?
Correct Answer
C. 1999
Explanation
The squirrel population decreased the most in 1999. This can be seen from the graph where the population is at its highest in 1997 and then sharply declines in 1999.
6.
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 population increased from 1994-1997 because the graph shows an upward trend during this time period. The number of squirrels increased steadily, indicating a growth in the population.
7.
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
Based on the graph, the number of squirrels reaches its lowest point in a certain year. At this point, the population size is indicated as 200 squirrels. Therefore, the size of the population the year the number of squirrels reached its lowest point is 200 squirrels.
8.
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 means physically counting or visually observing each individual in the population. It is a direct way to determine the size of a population and gather information about its characteristics.
9.
Counting fiddler crab holes on the tidal flats on an island is a _____________________ method of determining fiddler crabs population.
Correct Answer
E. Indirect observation
Explanation
Counting fiddler crab holes on the tidal flats on an island is an indirect method of determining fiddler crab population. Instead of directly observing and counting the crabs themselves, this method relies on the assumption that each hole represents an individual crab. By counting the number of holes, researchers can estimate the population size without having to physically capture or disturb the crabs. This indirect observation technique is useful when direct observation is not feasible or practical.
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. With fewer individuals being born to replace those who are dying, the population gradually declines. Therefore, the correct answer is that the population will generally decrease.
11.
A starfish grouping is 10 meters long and 5 meters wide. In a 1 square meter area, you count 20 starfish.
Estimate the population of starfish in the grouping.
Correct Answer
C. 1,000
Explanation
Based on the given information, we know that in a 1 square meter area, there are 20 starfish. To estimate the population of starfish in the entire grouping, we need to find the total number of square meters in the grouping. Since the grouping is 10 meters long and 5 meters wide, the total area of the grouping is 10 meters x 5 meters = 50 square meters. Therefore, we can estimate that the population of starfish in the grouping is 50 square meters x 20 starfish per square meter = 1,000 starfish.
12.
Check the conditions that can limit the growth of a population:
Correct Answer
A. Temperature and rainfall
Explanation
Temperature and rainfall are factors that can limit the growth of a population. Both temperature and rainfall affect the availability of resources and the overall environmental conditions. Extreme temperatures can be detrimental to the survival and reproduction of certain species, while inadequate or excessive rainfall can impact the availability of water and food sources. Therefore, variations in temperature and rainfall can directly influence the carrying capacity of an ecosystem and limit the growth of a population.
13.
What is the population density of the flamingos in the pond?
Correct Answer
A. 2.5 flamingoes per square meter
Explanation
The correct answer is 2.5 flamingoes per square meter. This means that there are 2.5 flamingoes on average within every square meter of the pond. This measurement helps to determine the concentration of flamingoes in the given area, indicating how crowded or sparse their population is.
14.
What is a producer?
Correct Answer
A. An organism that makes its own food energy.
Explanation
A producer is an organism that is capable of producing its own food energy through a process called photosynthesis. This process involves using sunlight, water, and carbon dioxide to produce glucose and oxygen. Examples of producers include plants, algae, and some bacteria. They are able to convert light energy into chemical energy, which can be used as a source of food and energy for themselves and other organisms in the ecosystem.
15.
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 capturing and marking a certain number of individuals in a population, releasing them back into the wild, and then recapturing a subsequent sample of individuals to see how many are marked. By comparing the ratio of marked to unmarked individuals in the recaptured sample, scientists can estimate the total population size.
16.
In general, which is a true statement about population size:
Correct Answer
C. If birth rate > death rate, population size increases
Explanation
If the birth rate is higher than the death rate, it means that more individuals are being born than are dying. This results in a net increase in the population size over time. Therefore, the statement "if birth rate > death rate, population size increases" is true.
17.
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 is used to estimate the size of a population. It states 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 assumes that the proportion of marked individuals in the recaptured sample represents the proportion of marked individuals in the entire population. By using this formula, researchers can estimate the total population size based on the number of marked and recaptured individuals in a sample.
18.
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
Indirect observation may be used when a population is small or difficult to find. This is because direct observation may not be feasible or practical in such cases. Indirect observation methods, such as using remote sensing technologies or studying indirect signs of the population's presence, can provide valuable information about the population size and dynamics. Additionally, indirect observation can also be useful when studying elusive or secretive species that are hard to detect or study directly. Overall, indirect observation allows ecologists to gather data and estimate population parameters in situations where direct observation is challenging or not possible.
19.
Suppose a population of 50 mice has produced 175 young.
If 159 mice died, how many mice are now in the population?
(Assume for this question that no mice have moved into or out of the population for other reasons).
Correct Answer
A. There would be a population of 66 mice.
Explanation
If 50 mice produced 175 young, then the total number of mice in the population would be 50 + 175 = 225. However, if 159 mice died, then the total number of mice in the population would be 225 - 159 = 66. Therefore, there would be a population of 66 mice now.
20.
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 (sample) and then apply multiples of that area to the larger area. By taking a representative sample from the larger population, we can estimate the total population size based on the observed count within the sample area. This method assumes that the distribution and density of organisms within the larger area are relatively uniform, allowing for accurate extrapolation from the sample.
21.
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 a certain period of time. It implies that the death rate or emigration rate is higher than the birth rate or immigration rate, resulting in a decrease in the overall population size.
22.
A mouse, raccoon, and hawk are all members of the same:
Correct Answer
C. Community
Explanation
A community refers to a group of different species living together in the same area and interacting with each other. In this case, a mouse, raccoon, and hawk are all different species, but they can coexist and interact within the same community. Therefore, the correct answer is community.
23.
All of the following are examples of limiting factors except:
Correct Answer
A. Time
Explanation
Time is not a limiting factor because it does not directly restrict the growth or survival of a population. Limiting factors are environmental factors that limit the growth, abundance, or distribution of a population. Food and water, space, and weather can all act as limiting factors by influencing the availability of resources, habitat suitability, and the ability to adapt to changing environmental conditions. However, time itself does not have a direct impact on these factors.
24.
The population can change in size when:
Correct Answer
C. When new members join the population or when members leave the population
Explanation
The correct answer is when new members join the population or when members leave the population. This is because the population size can increase when new individuals are born or immigrate into the population, and it can decrease when individuals die or emigrate out of the population. The other options mentioned in the question (birth rate equals death rate and emigration rate equals birth rate) do not necessarily result in a change in population size, as they only indicate a balance between births and deaths or emigration and immigration.
25.
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 the characteristics of a larger population by observing only a subset of that population. This approach is commonly used in statistical analysis and research, where it is often impractical or impossible to collect data from every individual in a population. By taking a representative sample and making assumptions about the larger population, researchers can make educated guesses about the characteristics or values of interest. This allows for more efficient and cost-effective data collection and analysis.
26.
The largest population that an area can support is called:
Correct Answer
H. Carrying capacity
Explanation
Carrying capacity refers to the maximum population size that a given environment can sustain indefinitely, taking into account the availability of resources such as food, water, and space. It represents the upper limit beyond which the population cannot grow due to resource limitations.
27.
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 specific area of a given size. It is a measure of how crowded or concentrated a population is within a particular space. It is calculated by dividing the total number of individuals in a population by the total area they occupy. This measure helps in understanding the distribution and abundance of a population within its habitat and provides insights into the interactions between individuals and their environment.
28.
The study of the living things and how they interact is called:
Correct Answer
K. Ecology
Explanation
Ecology is the study of living things and how they interact with each other and their environment. It focuses on the relationships and dynamics between organisms, as well as their interactions with their physical surroundings. Ecology helps us understand the distribution and abundance of organisms, their behaviors, and the flow of energy and nutrients in ecosystems. It also plays a crucial role in understanding and addressing environmental issues and conservation efforts.
29.
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. When groups leave or are separated from their population to pursue a need, such as finding resources or establishing new territories, it is called emigration. This process can have significant effects on the population dynamics and distribution of organisms.
30.
What is the one weather condition that can limit the growth of a population?
Correct Answer
A. Snow or a snowstorm.
Explanation
Snow or a snowstorm can limit the growth of a population because it can result in decreased food availability, reduced mobility, and increased mortality rates for certain species. Snow can cover vegetation, making it inaccessible for herbivores to feed on, and can also make it difficult for predators to catch their prey. Additionally, snowstorms can cause extreme cold temperatures, leading to hypothermia and death for animals that are not adapted to survive in such conditions. Therefore, the presence of snow or a snowstorm can significantly impact the ability of a population to grow and thrive.