Answer:
Ozone (O₃) gas
Explanation:
In the Earth's stratosphere, oxygen gas (O₂) is combined with atomic oxygen (O) to form ozone gas (O₃). This is very important because ozone protects the life on Earth from ultraviolet (UV) radiation from the Sun. UV radiation is high-energy radiation, and it is very dangerous for living organisms. Ozone molecule (O₃) absorbs UV radiation and it breaks down by forming O₂ and atomic oxygen (O) again. In this way, it protects the Earth from nocive radiation.
Answer:
Explanation:
Algae, phytoplankton and zooplankton
Ans.
Chromatin molecules are made up of DNA and histone proteins. Modification of chromatin structure include covalent, post-translational changes in histone proteins, present in chromation. Acetylation and methylation are two important histone modifications that affect structure of chromatin molecules.
Acetylation involves addition of an acetyl group to histones that increases transcription of DNA by loosen the association between DNA and nucleosome.
Methylation involves addition of a methyl group to histones that results in condensation of chromatin molecule and thus, decreases transcription of DNA.
Both acetylation and methylation are reversible processes.
Many chromatin modifications are genetic, means they can pass from one generation to another generation, called epigenetic modifications.
Thus, options B), C), D), E), and F).
Answer:
1. the DNA of which has been modified using genetic engineering methods. In most cases, the aim is to introduce a new trait to the plant which does not occur naturally in the species.
2. GM crops are made through a process known as genetic engineering. Genes of commercial interest are transferred from one organism to another. Two primary methods currently exist for introducing transgenes into plant genomes. The first involves a device called a 'gene gun'.
3. Crops do not damage the environment simply because they are GM. Some farming practices, such as the overuse of herbicides resulting in the excessive eradication of wild plants from farmland have been shown to harm the environment. These problems are similar for non-GM and GM crops.
