1) Why are Predators important?  

2. How can natural selection explain the origin of new species and higher orders of life?

3. What is the importance of keystone specie? Give examples

4. What are emergent diseases? Give a few examples, and de- scribe their cause and effects.

5. How do bacteria acquire antibiotic resistance? How might we prevent this?

6. Describe the rock cycle and name the three main rock types that it produces

Answer:

1. Why are Predators important?  

A food web is a complex web of interactions between species, each of which is attempting to obtain the nutrients it requires for growth and reproduction. Predators are predators that prey on other species by catching and killing them. They are still regarded as vital to our climate. One explanation is that prey animals such as deer constantly move around to avoid predators. This, in turn, has a positive effect on the environment's biomass. The number of trees, plants, bushes, and grasses that grow in that area increases, attracting a variety of insects and other organisms. Along lakes, soil erosion is often avoided. Top predators provide support to lower-level species. This is accomplished in the following manner. Consider wolves that prey on coyotes, thus reducing the coyote population. The population of coyote prey increases as a result of this. Another significant consideration is that predators tend to prey on the sickest people. This reduces disease transmission and provides a stable habitat for the prey.

2. How can natural selection explain the origin of new species and higher orders of life?

New species do not grow on their own. Populations change over time. Since individuals in a population differ, some are better able to survive and replicate under some environmental conditions than others. These individuals are more likely to survive and reproduce, passing on their beneficial characteristics to the next generation. The general population evolves over time.

If a population of organisms is geographically or behaviorally separated from the rest of its species, it may be exposed to various selective pressures. In the isolated population, changes will accumulate. If those changes were drastic enough that the splinter group could not or would not mate with the original stock on a regular basis, the splinter group would be reproductively separated and on its way to becoming a new species (allopatric speciation).

3. What is the importance of keystone specie? Give examples

A keystone species is one that has a disproportionately high effect on the environment in comparison to its abundance. Many habitats would perish if a keystone species did not exist. The cheetah, for example, is a keystone species in the African Savannah, controlling the deer population. If it wasn't present, the deer population would skyrocket, consuming all grasses and causing a grass shortage. As a result, it is critical to the ecosystem's survival.

4. What are emergent diseases? Give a few examples, and de- scribe their cause and effects.

Various diseases have been identified and have existed for a long time. With the concerted efforts of health organizations and governments, some of these diseases have been eradicated, thus improving the living standards of people in developed and developing countries. Pathogens such as bacteria, viruses, parasites, and protozoans cause a variety of diseases. The pandemic situation arose in 1918 as a result of the outbreak of influenza, and it is estimated that one-third of the population was infected with the virus, with many people dying as a result. Another recent pandemic, Coronavirus, has resulted in millions of people testing positive for the virus, with many of them dying as a result. Since the Coronavirus was not present on the planet at the time, it infected humans and became one of the most infected and deadly diseases. 

Emergent diseases are diseases that were previously unknown or had been absent from existence for at least 20 years. Emergent diseases include the latest strain of swine flu that is now spreading, the noble Coronavirus, and deadly diseases such as Ebola virus and Marburg diseases. Some of the latest diseases that have emerged are immune to the drugs used in the previous attack. The following are examples of outbreaks caused by the extremely lethal infectious disease:

• Hantavirus in 1993
• Swine flu in 2009
• Cholera in 1992
• Mad cow disease in 1997
• Pneumonic plague in 1994
• SARS in 2003
• Bird flu in 2004
• Coronavirus in 2020

5. How do bacteria acquire antibiotic resistance? How might we prevent this?

Drugs, antibiotics, and other chemicals intended to destroy bacteria, insects, and infectious agents become immune. Malaria, for example, was once a deadly disease that was believed to be eradicated but then reappeared. It is estimated that millions of people have died in Africa as a result of Malaria, with many of the victims being children. This is because the protozoa have developed resistance to the medications that are used to treat the diseases. Malaria is transmitted by protozoa that are carried by mosquitoes, which are the disease's vectors. Just a few thousand people were infected with malaria because the protozoa were destroyed by DDT spraying. Because of climate change and habitat changes, the disease has spread in areas where there had previously been no cases of malaria.

Two techniques were used to make the bacteria immune to the drugs:

1. Antibiotic-resistant bacteria grow their DNA, and mutations in the DNA of microbes occur, rendering them resistant to the particular antibiotic. Since bacteria mutate their DNA, if they are treated with the same antibiotic after the mutation, they can continue to replicate and therefore be protected from the specific chemicals.
2. Another way of achieving resistance is when dangerous bacteria and harmless bacteria conjugate, and the gene for antibiotic resistance is passed on to other strains, resulting in the evolution of new resistant supervirulent organisms.

This can be avoided by modifying the antibiotic and the way it attacks bacteria. Another way to avoid resistance is to avoid spraying chemicals all over the environment, causing microorganism species to become immune to the same chemical all over the area. As a result, it's important to use antibiotics and harmful chemicals with caution, and to adjust them at regular intervals so that advanced microbes don't become resistant to new chemicals and drugs.

6. Describe the rock cycle and name the three main rock types that it produces

Earth is a world with a diverse range of geological resources, including plastic, glass, synthetic fiber, iron, copper, aluminum, and non-metal resources such as sand and clay. Human actions are a significant contributor to the destruction of the planet. Earth is a complex world with a layered sphere that looks like this:

• Core - It's thick and made up of a fiery mass of metals. The core is made up of two parts: a solid inner core and a semisolid outer core that generates the magnetic field.
• Mantle - Since it contains a large number of light elements such as oxygen and silicon, it has a lower density than the nucleus.
• Crust - The planet's most outer layer. This layer is cool and light, and it has brittle rocks in it.

The following are the eight most common elements found in the entire earth and crust. Posted in the explanation.

The rock cycle recreates and recycles the rocks. Rock is a firm, intact mixture of one or more minerals. The rock cycle describes the formation, obliteration, and alteration of rocks.

The three most common types of rock are:

1. Igneous Rocks - These are generated by magma condensation.
2. Metamorphic Rocks - Metamorphosis is a process that creates these from pre-existing rocks.
3. Sedimentary Rocks - Lithification is a process that takes sediments and turns them into a solid.

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