1.
Population is determined by geographic distribution, biomass, and number of predators vs. number of plants.
Correct Answer
B. False
Explanation
The statement that "Population is determined by geographic distribution, biomass, and number of predators vs. number of plants" is false. While geographic distribution, biomass, and the predator-prey relationship can certainly influence population dynamics, they are not the sole determinants. Other factors such as availability of resources, reproductive rates, competition, and environmental conditions also play significant roles in determining population size.
2.
Name (first and last)
Correct Answer
N/A
3.
Student ID #
Correct Answer
N/A
4.
Population size is determined by the relationship between birth rate, death rate, immigration, and emigration.
Correct Answer
A. True
Explanation
The statement is true because population size is indeed influenced by the factors mentioned: birth rate, death rate, immigration, and emigration. Birth rate refers to the number of births in a population, while death rate refers to the number of deaths. Immigration is the movement of individuals into a population, and emigration is the movement of individuals out of a population. These factors collectively determine the overall size and growth of a population.
5.
Bacteria populations grow exponentially.
Correct Answer
A. True
Explanation
Bacteria populations grow exponentially because each bacterium can divide and produce multiple offspring. As the number of bacteria increases, the rate of reproduction also increases, leading to exponential growth. This means that the population size doubles over a certain period of time, resulting in a rapid increase in numbers. This exponential growth pattern is commonly observed in bacterial populations under favorable conditions where there are abundant resources and no limiting factors.
6.
Exponential growth is shown on a "U" shaped curve.
Correct Answer
B. False
Explanation
Exponential growth is not shown on a "U" shaped curve. Exponential growth is characterized by a rapid increase over time, whereas a "U" shaped curve typically represents a situation where there is an initial decrease followed by an increase. Therefore, the statement is false.
7.
Populations grown exponentially under reasonable conditions with enough resources for one year.
Correct Answer
B. False
Explanation
Exponential population growth refers to a rapid increase in the number of individuals in a population over time. However, this growth is not sustainable indefinitely, as it requires an unlimited supply of resources. In reality, populations can only grow exponentially for a limited period before reaching a carrying capacity, where available resources become limited and growth slows down. Therefore, populations do not continue to grow exponentially under reasonable conditions with enough resources for one year, making the statement false.
8.
Logistic growth occurs when exponential growth speeds up.
Correct Answer
B. False
Explanation
Logistic growth occurs when exponential growth slows down and reaches a maximum value known as the carrying capacity. In logistic growth, the population initially grows exponentially but eventually levels off as resources become limited. Therefore, the given statement is incorrect as logistic growth does not occur when exponential growth speeds up, but rather when it slows down.
9.
A decreasing birth rate slows population growth.
Correct Answer
A. True
Explanation
A decreasing birth rate slows population growth because when the number of births decreases, there are fewer individuals being added to the population. This means that the rate at which the population is growing decreases. Therefore, the statement is true.
10.
Carrying capacity is the maximum number of individuals within a population that an environment can support.
Correct Answer
A. True
Explanation
Carrying capacity refers to the maximum number of individuals that a given environment can sustain within a population. This means that once the population reaches its carrying capacity, the environment cannot support any more individuals and may lead to competition for resources, increased predation, or other negative impacts. Therefore, the statement that the given answer is true is correct.
11.
Limiting factors cause population growth to increase.
Correct Answer
B. False
Explanation
Limiting factors are factors that restrict or limit the growth of a population. These factors can include limited resources, competition for resources, predation, disease, and environmental conditions. Therefore, limiting factors actually cause population growth to decrease or slow down, rather than increase. So, the statement that limiting factors cause population growth to increase is false.
12.
Predator-prey relationship is an example of a density-dependent limiting factor.
Correct Answer
A. True
Explanation
A predator-prey relationship is an example of a density-dependent limiting factor because the population size of the predator and prey directly affect each other. As the prey population increases, there is more food available for predators, leading to an increase in the predator population. However, as the predator population grows, they consume more prey, causing a decrease in the prey population. This cycle continues, causing fluctuations in the population sizes of both predator and prey, ultimately regulating their numbers. This relationship is dependent on the density or abundance of both species and is a classic example of how population dynamics are influenced by interdependencies between species.