In this video lesson, you will learn about the ecology topics that are most frequently asked in the ENEM. Almost half of the biology questions on this test are about ecology. Of course, the first thing you need to know is that ecology studies the relationships between living beings and also the relationships between these living beings and the environment in which they live. One of the ecology topics that is most frequently asked in the ENEM is biogeochemical cycles. These cycles are nothing more than processes that occur in nature to ensure the recycling of chemical elements in the environment. When it comes to the ENEM, the biogeochemical cycles that appear most are the carbon and nitrogen cycles. Just to give you an idea, in the last 5 years, the carbon cycle has appeared five times in the ENEM. The nitrogen cycle has appeared an incredible nine times in this test. And when we talk about the carbon biogeochemical cycle, we need to remember that this cycle is directly linked to another ecology topic that is frequently asked in the ENEM, which is food chains. After that, you will learn about the second most common topic in ecology questions, which is environmental impacts, such as air pollution and water pollution. Remember that pollution is any human-caused process that adds material or energy to the soil, water, and atmosphere that causes chemical and physical changes in the environment. Air pollution can be defined as the presence in the air of substances from human activity that are dangerous to our health, such as sulfur dioxide, ozone, and nitrogen dioxide. The main atmospheric problem today is the greenhouse effect, which has been changing the climate of our planet. But human activities do not only cause air pollution, since water pollution also appears a lot in the ENEM. The topic about water pollution that appears most in this test is eutrophication, which occurs because of the accumulation of nutrients in the water, such as phosphorus and nitrogen, which are nutrients present in industrial and domestic sewage. And to finish this great ecology video lesson, you will learn about the most common topic in ecology in the ENEM, which is the topic of environmental preservation. It is worth remembering that there are several topics on environmental preservation that may appear in the questions. One of them is bioremediation, which is a process that uses bacteria, fungi and plants to degrade pollutants present in the environment, such as fuels and solvents. Another environmental preservation strategy that appears in the ENEM exam is ecological corridors, which are nothing more than green areas that aim to connect two forest fragments. In addition, biological control, which is nothing more than the use of species considered natural enemies to combat agricultural pests and disease-causing insects. I am sure that several topics discussed in this video lesson will be on your exam. Happy studying and have a great exam. MEET MY NETWORKS - - - - - - - - - - - - - - - - - - - - - - - - - - ⭐ INSTAGRAM: / paulojubilut ⭐ TIKTOK: / paulojubilut ⭐ My PRE-COLLEGE: https://bit.ly/aprova_total WELCOME TO MY CHANNEL - - - - - - - - - - - - - - - - - - - - - - - - - - My name is Paulo Jubilut, I am a biologist and I have been here on YouTube since 2011 bringing the universe of biology to social networks. On this channel, you will find frequent videos about how biology connects with your daily life, and the best part: in a simple way to understand.