Question

Part III: Answer "a" for true and "b" for false 79. Autotrophs are also known as consumers. 80. A lichen is an example of a pioneer species for primary succession 81. No life exists in the aphotic zone of the ocean where no light can penetrate. 82. Deciduous plants annually drop their leaves. 83. Hurricanes are likely to become more intense as oceans get warmer 84. Fire is an example of a density dependent limiting factor 85. Overcrowding often makes organisms more susceptible to disease. 86. In a balanced ecosystem, predators and prey control the populations of each other 87. It is common to find 10 trophic levels in a food chain. 88. Exotic species are a major cause of biodiversity loss 89. Most extinctions today are caused by natural changes to the biosphere. 90. Ozone is depleted by the enhanced greenhouse effect.

Answer 1

Q. 79. Answer- false (b).. This is because autotrophs are producer and not consumers.

Q. 80 Answer- True (a). This is because lichens are the first colonizers of a bare rock.

Q. 81 Answer - False (b). This is because in aphotic zone life exists but photosynthetic organisms do not exist as there is no light for the process of photosynthesis.

Q. 82 Answer - True (a). Deciduous trees drop their leaves every year usually during autumn season.

Q. 83 Answer - True (a). Warming temperature heat up the surface of the oceans, increasing evaporation and putting more water vapor into the atmosphere. This in turn provides added fuel for storms as they travel over open oceans.

Q.84 Answer - True (a).  In nature, population size and growth are limited by many factors. Some are density-dependent, while others are density-independent. Examples include natural disasters like forest fires. Limiting factors of different kinds can interact in complex ways to produce various patterns of population growth.

Q. 85 Answer - True (a). Disease can spread very fastly in an overcrowded population.

Q. 86 Answer - True (a). Predation control the populations of organism.

Q. 87 Answer - False (b).  Energy is lost when it is transferred from one trophic level to the next. Approximately 10% of the stored energy of a trophic level could be transferred to the consumers of next level. So 10 trophic levels are not possible.

Q. 88 Answer - True (a). Exotic species cause the extinction of local species by changing the natural environmental conditions of that area.

Q. 89 Answer - False (b). Most extinctions today are caused by human activities.

Q. 90 Answer - True (a). Ozone is depleted due to greenhouse gases like Chloro Floro Carbon etc.