1.
Refer to the illustration. The photosynthetic algae are
Correct Answer
B. Producers
Explanation
The correct answer is producers because photosynthetic algae are capable of producing their own food through the process of photosynthesis. They use sunlight, carbon dioxide, and water to produce glucose and oxygen. As producers, they form the base of the food chain by providing energy and nutrients to other organisms in the ecosystem.
2.
The finches that Darwin studied differed in the shape of their beaks. According to Darwin, the finches probably
Correct Answer
D. Had become adapted to eating different diets.
Explanation
According to Darwin, the finches that he studied had different beak shapes because they had become adapted to eating different diets. This means that each type of finch had developed a specific beak shape that allowed them to efficiently consume the particular types of food available in their environment. This adaptation occurred over time as the finches faced different selective pressures based on the available food sources. Thus, the finches with different beak shapes were able to survive and reproduce successfully due to their specialized diets.
3.
As a population reaches its carrying capacity, resources become more scarce. Which of the following would increase within the population?
Correct Answer
C. Competition
Explanation
As a population reaches its carrying capacity, competition among individuals for limited resources becomes more intense. This is because there are more individuals competing for the same amount of resources, such as food, water, and space. Therefore, the correct answer is competition.
4.
Which resource is considered renewable?
Correct Answer
B. Wind
Explanation
Wind is considered a renewable resource because it is generated by natural processes and can be replenished indefinitely. Unlike coal, natural gas, and oil, which are finite resources that take millions of years to form, wind is constantly available and does not deplete over time. Wind energy can be harnessed through wind turbines to generate electricity, making it a clean and sustainable source of power.
5.
Refer to the illustration. The American Revolution began in 1776. According to the graph, what was the approximate world population at that time?
Correct Answer
D. I billion
Explanation
According to the graph, the world population in 1776 was approximately 1 billion.
6.
Refer to the illustration. Because the two species of barnacles attempt to use the same resources, they are
Correct Answer
B. Competitors.
Explanation
The correct answer is competitors. In the given illustration, it is stated that the two species of barnacles attempt to use the same resources. This indicates that they are in competition with each other for those resources. Therefore, they are considered competitors.
7.
Which of these activities causes the greatest loss of biodiversity?
Correct Answer
A. Habitat loss
Explanation
Habitat loss causes the greatest loss of biodiversity. When natural habitats are destroyed or altered, it directly affects the species that rely on those habitats for survival. It leads to the displacement, decline, or extinction of many species, resulting in a significant loss of biodiversity. Habitat loss can occur due to various human activities such as deforestation, urbanization, and conversion of land for agriculture or infrastructure development. These activities disrupt the delicate balance of ecosystems and have long-term negative impacts on the diversity of plant and animal species.
8.
Refer to the illustration. Which time period shows exponential growth of the population?
Correct Answer
D. Period B
Explanation
Period B shows exponential growth of the population because the population is increasing at an accelerating rate. In this period, the population is growing rapidly and the rate of growth is proportional to the current population size. This is characteristic of exponential growth, where the population size doubles or increases at a constant rate over a fixed time period.
9.
The water cycle continuously moves water between the atmosphere, land, and
Correct Answer
B. Oceans
Explanation
The water cycle continuously moves water between the atmosphere, land, and oceans. This is because water evaporates from the surface of the oceans, forms clouds in the atmosphere, and then falls back to the land as precipitation. From the land, water can flow into rivers and eventually make its way back to the oceans. Therefore, the oceans play a crucial role in the water cycle by serving as a major source of evaporation and a destination for water runoff.
10.
The major idea that Darwin presented in his book The Origin of Species was that
Correct Answer
C. Species changed over time by natural selection.
Explanation
In his book The Origin of Species, Darwin introduced the concept of natural selection, which is the process by which species change over time. He argued that individuals with advantageous traits are more likely to survive and reproduce, passing on those traits to future generations. This leads to the gradual evolution of species over time. Therefore, the major idea presented by Darwin in his book was that species change over time through the mechanism of natural selection.
11.
Renewable sources of energy
Correct Answer
B. Can replenish themselves naturally.
Explanation
Renewable sources of energy can replenish themselves naturally because they are derived from constantly available resources such as sunlight, wind, water, and geothermal heat. Unlike fossil fuels, which are finite and non-renewable, renewable energy sources can be continuously harnessed without depleting the Earth's resources. This makes them a sustainable and environmentally friendly option for meeting our energy needs.
12.
Refer to the illustration. Level A is composed of
Correct Answer
B. Producers
Explanation
The correct answer is "producers" because level A in the illustration is composed of organisms that are capable of producing their own food through photosynthesis. Producers are typically plants or algae that convert sunlight into energy, forming the base of the food chain. This is supported by the fact that the other options, such as omnivores, herbivores, and carnivores, are all consumers that rely on consuming other organisms for energy rather than producing their own.
13.
Natural selection is the process by which ?
Correct Answer
A. Organisms with traits well-suited to their environment reproduce at a greater rate than less well-adapted organisms in the same environment.
Explanation
Natural selection is the process by which organisms with traits well-suited to their environment reproduce at a greater rate than less well-adapted organisms in the same environment. This means that individuals with advantageous traits are more likely to survive and pass on their genes to the next generation, leading to a gradual change in the genetic characteristics of a population over time. This process is driven by the survival and reproduction of the fittest individuals, resulting in the adaptation of a species to its environment.
14.
What happens in a food chain if one of the lower consumers is eliminated or reduced in numbers?
Correct Answer
C. Those higher in the food chain must find alternate sources of food; those lower in the food chain must be controlled by other consumers
Explanation
If one of the lower consumers in a food chain is eliminated or reduced in numbers, those higher in the food chain must find alternate sources of food. This is because the higher consumers rely on the lower consumers as their primary source of food. Without the lower consumers, the higher consumers must adapt and find other organisms to prey upon. Additionally, those lower in the food chain must be controlled by other consumers to prevent overpopulation and imbalance in the ecosystem.
15.
High biodiversity often helps make an ecosystem more
Correct Answer
B. Resilient.
Explanation
High biodiversity often helps make an ecosystem more resilient. This is because a diverse ecosystem contains a variety of species with different traits and abilities to adapt to changes. When a disease or disturbance occurs, a diverse ecosystem is more likely to have species that can survive and recover, ensuring the overall stability and functioning of the ecosystem. Therefore, high biodiversity contributes to the resilience of an ecosystem.
16.
Refer to the illustration. At each trophic level, the energy stored in the organisms in that level is about
Correct Answer
D. Ten percent of the energy in the level below it.
Explanation
The correct answer is ten percent of the energy in the level below it. This is because of the ecological pyramid, which shows that energy is transferred between trophic levels. As energy moves up the pyramid, only about 10% of the energy is transferred to the next level, while the rest is lost as heat or used for metabolic processes. Therefore, each trophic level contains only about 10% of the energy from the level above it.
17.
All living things are made of
Correct Answer
A. Carbon
Explanation
Carbon is the correct answer because it is an essential element found in all living organisms. It is the basis of organic chemistry and is involved in the structure of proteins, carbohydrates, lipids, and nucleic acids. Carbon atoms can form strong bonds with other elements, allowing for the creation of complex molecules necessary for life. Carbon is also a key component of the carbon cycle, which plays a crucial role in maintaining the balance of gases in the Earth's atmosphere.
18.
Nitrogen is a component of
Correct Answer
A. Fats
Explanation
Nitrogen is not a component of fats. Fats are composed of carbon, hydrogen, and oxygen. Nitrogen is present in proteins, which are made up of amino acids that contain nitrogen atoms. Water and carbohydrates also do not contain nitrogen.
19.
Which of the following would not be included in a description of an organism's niche?
Correct Answer
C. Its number of chromosomes
Explanation
An organism's niche refers to its role and position in its environment, including its interactions with other organisms and its habitat preferences. The number of chromosomes an organism has is a genetic characteristic that does not directly relate to its niche. The number of chromosomes does not determine an organism's habitat, interactions, or behavior, which are all important elements of its niche.
20.
Linnaeus's two-word system for naming organisms is called
Correct Answer
A. Binomial nomenclature.
Explanation
Linnaeus's two-word system for naming organisms is called binomial nomenclature. This system involves using the genus and species names to give each organism a unique scientific name. The genus name represents a group of closely related species, while the species name identifies the specific organism within that genus. This system allows scientists to have a standardized and universally recognized way of naming and classifying organisms. The other options, taxonomic evolution and Greek polynomials, are not accurate terms for Linnaeus's naming system.
21.
As the density of a population increases, the effects of starvation and disease also often increase. These are which kind of factors?
Correct Answer
C. Density-dependent
Explanation
As the density of a population increases, the effects of starvation and disease also often increase. This suggests that starvation and disease are influenced by the density of the population. Therefore, they are density-dependent factors, meaning that their impact on the population is dependent on its density.
22.
The disappearance of a species from the Earth is referred to as
Correct Answer
A. Extinction
Explanation
Extinction refers to the disappearance of a species from the Earth. It occurs when a species no longer exists in any part of its natural habitat. This can happen due to various factors such as habitat loss, climate change, pollution, and overhunting. Extinction is a natural process that has been occurring throughout Earth's history, but human activities have greatly accelerated the rate of extinction in recent times. This loss of biodiversity has significant ecological and environmental consequences and threatens the balance of ecosystems.
23.
Which of the following natural cycles involves photosynthesis and cellular respiration?
Correct Answer
C. Carbon cycle
Explanation
The carbon cycle involves photosynthesis and cellular respiration. During photosynthesis, plants and other autotrophs use sunlight to convert carbon dioxide into glucose, releasing oxygen as a byproduct. This glucose is then broken down through cellular respiration by organisms, including plants and animals, to release energy and produce carbon dioxide. This continuous exchange of carbon between the atmosphere, plants, and animals is known as the carbon cycle.
24.
A producer is the ecological role that
Correct Answer
C. Converts the energy of sunlight into high-energy organic compounds.
Explanation
The correct answer is "converts the energy of sunlight into high-energy organic compounds." This is because a producer, such as plants or algae, uses photosynthesis to convert sunlight into energy and store it in the form of organic compounds like glucose. Producers are at the bottom of the energy pyramid and provide energy for all other organisms in the ecosystem.
25.
Two species occupying the same niche would be __________ with each other.
Correct Answer
A. Competition
Explanation
When two species occupy the same niche, they are likely to compete with each other for limited resources such as food, water, and habitat. This competition can lead to a decrease in population size or even the extinction of one of the species. Therefore, the correct answer is "competition".
26.
The isolation of two groups within a population from each other, and their adaptation to the point of being no longer able to interbreed is called
Correct Answer
C. Speciation.
Explanation
Speciation refers to the process by which two groups within a population become isolated from each other and adapt to the point where they can no longer interbreed. This isolation and subsequent adaptation lead to the formation of new species. Population genetics is the study of how genetic variation changes within a population over time. Gradualism refers to the idea that evolutionary change occurs slowly and gradually over long periods of time. Convergence refers to the process by which unrelated organisms evolve similar traits due to similar environmental pressures.
27.
Commensalism, mutualism, and parasitism are all forms of
Correct Answer
B. Symbiosis
Explanation
Commensalism, mutualism, and parasitism are all forms of symbiosis. Symbiosis is a close and long-term interaction between two different species, where at least one species benefits. In commensalism, one species benefits while the other is unaffected. In mutualism, both species benefit from the interaction. In parasitism, one species benefits while the other is harmed. These different forms of symbiosis highlight the diverse ways in which species can interact and depend on each other for survival and reproduction.
28.
A community includes
Correct Answer
D. All living organisms living in a certain area.
Explanation
The correct answer is "all living organisms living in a certain area." This option accurately defines a community as a group of living organisms that inhabit a specific area. It includes plants, animals, and other organisms that interact with each other and their environment. The other options are not comprehensive enough to encompass the entire community, as they either focus on only one species or exclude non-living elements.
29.
All the members of one species in a given area is its
Correct Answer
D. Population.
Explanation
Population refers to all the members of a particular species that live in a specific area. Biodiversity refers to the variety of different species in an area, not just one species. Carrying capacity refers to the maximum number of individuals that an environment can support. Growth is a broad term that can refer to various aspects of a species' development. Therefore, the correct answer is population.
30.
Bacteria are one-celled organisms without membrane-enclosed organelles. They are classified as
Correct Answer
A. Prokaryotes.
Explanation
Bacteria are considered prokaryotes because they lack membrane-enclosed organelles. Prokaryotes are single-celled organisms that do not have a nucleus or any other membrane-bound structures within their cells. In contrast, eukaryotes, such as plants and animals, have cells that contain a nucleus and other membrane-bound organelles. Therefore, the correct answer is prokaryotes.
31.
When environmental conditions favor one allele of a gene over another, _____ is occurring.
Correct Answer
D. Natural selection
Explanation
When environmental conditions favor one allele of a gene over another, natural selection is occurring. This means that individuals with the favored allele have a higher chance of surviving and reproducing, passing on this allele to future generations. Over time, this can lead to a change in the frequency of alleles in a population, as the favored allele becomes more common. Natural selection is a key mechanism of evolution, driving the adaptation of populations to their environment.
32.
Calling a species by its genus and species name, such as Homo sapiens, is using
Correct Answer
B. Binomial nomenclature.
Explanation
Binomial nomenclature is the system of naming species by their genus and species name. This system was developed by Carl Linnaeus and is widely used in the field of taxonomy to provide a standardized and universally recognized way of identifying and classifying organisms. Cladistics is a method of classification based on common ancestry, phylogeny is the study of evolutionary relationships, and taxonomy is the science of classification. However, neither of these options specifically refers to the use of genus and species names to identify species.