<h3><u>Answer;</u></h3>
Gene therapy to correct defective genes that cause diseases.
<h3><u>Explanation</u>;</h3>
- Gene therapy refers to the procedure that involves the introduction of nucleic acids (DNA or RNA) into the cells of an organism for the purpose of correcting abnormalities, such as a mutations or in other words to treat a genetic disease.
- Gene therapy entails bringing a normal and functional gene known as a trans-gene into a cell with altered gene. Another method can bring RNA capable of partially regulating or blocking the expression of an altered gene.
- The nucleic acids are introduced into the patient's cells by means of a viral vector or injected directly into the cells in the form of naked DNA.
<u>Answer:</u>
Fossils are the sources to learn the changes on the earth and how much it changed in these years. Its provides us with information about the existence of plant and animals in the past.
Actually, the fossils we found till the date are the ancestors of the plants and animals that live today. Moreover, some fossils of animals are easily identifiable since they exist till the date.
But there are fossils of animals that exist no longer in the earth. By studying and analyzing the fossils, one can tell how life on the earth has changed.
Also, we can learn about the ancestors of the plants and animals and how their long life existed on earth.
In other words, one can learn where and how those organisms were lived. So that we can know about our ancient environments.
Ozone is formed by the reaction of of nitrous oxides and reactive organic substance catalyzed by sunlight. This is a photochemical reaction provided with ozone forming compounds and sunlight.
Acid rain is defined as nitrous(NO2) and sulfurous (SO2) compounds enter the atmosphere as smog thereby precipitating as acid rain. This is detrimental in the environment as well as in agriculture.
Global warming is precipitated by the burning of fossil fuels that increases carbon dioxide, a greenhouse gas that traps heat, in the atmosphere. The greenhouse effect is the main principle behind global warming.
Ocean acidification is when excessive carbon dioxide is dissolved in the oceans as carbonic acid thereby increasing the pH of the ocean. Increases in the pH of the ocean can affect the living conditions as well as industrial conditions near it.
Groundwater pollution is defined as contaminating the groundwater with the runoff from industrial agriculture including organic and inorganic wastes as well as infectious and nuclear wastes.
Algae blooms or algal blooms are precipitated by eutrophication or the increase in nutrients in water such as nitrogenous compounds and phosphorus from fertilizers. Eutrophication of water precipitates the abnormally high growth rate of algae.
Ozone layer destruction is associated with CFCs such as Freon and aerosols as these compounds neutralize and destroy ozone. These compounds form free radicals that convert ozone (O3) to oxygen (O2) thereby reducing its capability to protect the earth from UV radiation.
Deforestation is primarily caused by urbanization (cutting down trees to provide empty land in building structures) and industrial farming (converting forests into agricultural lands for farming).
<em>Answers: 1. H, 2. D, 3. E, 4. A, 5. B, 6. C, 7. G, 8. F</em>
The answer is A. antioxidants. Antioxidants is the defense
system of the body, it is also the involved prevention of the damage of the
cell; examples are aging, common reason of cancer and also different kinds of diseases.
There’s always a need to have antioxidants because our body needs protection
for the damage by the oxidation may cause.
