1.
The greenhouse effect is
Correct Answer
C. A natural pHenomenon due to absorption of sunlight and re-radiating of the heat.
Explanation
The greenhouse effect is a natural phenomenon due to the absorption of sunlight by the Earth's atmosphere and the re-radiation of heat back to the surface. This process is essential for maintaining the Earth's temperature and making it habitable for life. The greenhouse gases in the atmosphere, such as carbon dioxide and methane, trap the heat and prevent it from escaping into space. This natural greenhouse effect has been occurring for millions of years. Increased sunlight, increased plant life, and manmade hazards are not the primary causes of the greenhouse effect.
2.
Which of the following is NOT a greenhouse gas?
Correct Answer
C. Oxygen
Explanation
Oxygen is not a greenhouse gas because it does not trap heat in the Earth's atmosphere like carbon dioxide and methane do. Greenhouse gases are responsible for the greenhouse effect, which is the process by which the Earth's atmosphere absorbs and re-emits infrared radiation, leading to the warming of the planet. While oxygen is a vital component of the Earth's atmosphere and is necessary for life, it does not have the same warming effect as greenhouse gases.
3.
When habitats are fragmented so that populations are subdivided into several small and isolated groups, they form a
Correct Answer
D. Metapopulation.
Explanation
When habitats are fragmented into small and isolated groups, the populations within these groups are referred to as a metapopulation. A metapopulation is a collection of interconnected populations that exchange individuals through migration. This interconnectedness helps to maintain genetic diversity and prevent local extinctions. The concept of a metapopulation is important in conservation biology as it highlights the importance of maintaining habitat connectivity to ensure the long-term survival of species in fragmented landscapes.
4.
Critical species that are so important that their extinction causes major changes and may threaten other species existence constitute a
Correct Answer
C. Keystone species.
Explanation
A keystone species is a critical species that plays a crucial role in maintaining the balance and stability of an ecosystem. Its extinction can lead to significant changes in the ecosystem and may even threaten the existence of other species. The term "sink population" refers to a population that receives more emigrants than it sends, while "biodiversity hotspot" refers to an area with a high level of biodiversity. "Metapopulation" refers to a group of spatially separated populations of the same species, and "source population" refers to a population that sends out more emigrants than it receives.
5.
When patches get smaller and the organisms that live well deep inside large patches are exposed to less favorable conditions, this is
Correct Answer
A. The edge effect.
Explanation
The edge effect refers to the phenomenon where the conditions at the edge of a habitat differ from those in the interior. When patches get smaller, the organisms living deep inside are exposed to less favorable conditions, such as increased exposure to predators or harsher environmental factors. This change in conditions at the edge of the patch is known as the edge effect. It can have significant impacts on the distribution and survival of organisms within the habitat.
6.
Madagascar is considered a biodiversity "hotspot" because
Correct Answer
C. It contains a high concentration of unique species.
Explanation
Madagascar is considered a biodiversity "hotspot" because it contains a high concentration of unique species. This means that the island has a large number of species that are found nowhere else in the world. The isolation of Madagascar from other land masses allowed for the evolution of distinct and diverse species over millions of years. The unique flora and fauna of Madagascar make it a critically important area for conservation efforts and highlight the significance of preserving its ecosystems.
7.
Biodiversity "frontiers" are areas that
Correct Answer
C. Have many more species than formerly thought.
Explanation
Biodiversity "frontiers" are areas that have many more species than formerly thought. This means that these areas have a higher level of biodiversity than initially believed. It suggests that there is a greater variety of species present in these regions, which may have been previously overlooked or underestimated. This highlights the importance of conducting thorough surveys and research to accurately assess and understand the biodiversity of different ecosystems.
8.
The regulation of climate, cleansing of fresh water, and support of ecotourism are examples of _______ value drawn from biodiversity.
Correct Answer
C. Consumptive use
Explanation
The regulation of climate, cleansing of fresh water, and support of ecotourism are all examples of the consumptive use value drawn from biodiversity. Consumptive use refers to the direct utilization of natural resources for human needs, such as food, fuel, and materials. In this case, the benefits derived from biodiversity directly contribute to human well-being and economic activities, highlighting the importance of preserving and conserving biodiversity for sustainable development.
9.
Which statement is NOT true about biological diversity?
Correct Answer
B. Temperate forests have more biological diversity than the tropical rain forests.
Explanation
Temperate forests have more biological diversity than tropical rainforests. This statement is not true because tropical rainforests are known to have the highest levels of biological diversity compared to any other ecosystem on Earth. They are home to a wide variety of plant and animal species, many of which are endemic and found nowhere else. In contrast, while temperate forests also support diverse ecosystems, they generally have lower levels of species richness and endemism compared to tropical rainforests.
10.
Introduction of alien or exotic species into new ecosystems occurs by
Correct Answer
D. All of the above are correct
Explanation
The introduction of alien or exotic species into new ecosystems can occur through colonization when new settlers arrive in an area, accidental transport by ship or plane without anyone's knowledge, as well as through agricultural and horticultural activities. These activities can lead to the unintentional introduction of non-native species into an ecosystem, which can have negative impacts on the native flora and fauna. Therefore, all of the given options are correct explanations for the introduction of alien or exotic species into new ecosystems.