Answer: B
Explanation:
They inject their DNA into the cell, which reprograms that cell to become that virus. This is why viruses are so deadly and can spread throughout the body and to others easily, and efficiently.
Answer:
The answer is C
Explanation:
( Sorry not really good at explaining)
Answer:
<em>(I) Lamarckism or Theory of Inheritance of Acquired characters.</em>
This theory is based on the comparison between the contemporary species of Jean Baptiste de Lamarck's time to fossil records.
<em>(II) Darwinism or Theory of Natural Selection.</em>
Charles Darwin made an extensive study of nature for over 20 years, especially in 1831-1836 when he went on a voyage on the famous ship “H.M.S. Beagle” and explored South America, the Galapagos Islands and other islands.
<em>(III) Mutation theory of De Vries.</em>
The mutation theory of evolution was proposed by a Dutch botanist, Hugo de Vries (1848-1935 A.D.) in 1901 A.D. in his book entitled “Species and Varieties, Their Origin by Mutation”. He worked on evening primrose (Oenothera lamarckiana).
<em>(IV) Neo-Darwinism or Modern concept or Synthetic theory of evolution.</em>
The detailed studies of Lamarckism, Darwinism and Mutation theory of evolution showed that no single theory is fully satisfactory. Neo-Darwinism is a modified version of theory of Natural Selection and is a sort of reconciliation between Darwin’s and de Vries theories.
Answer:
The correct answer is: d.a nonpolar side chain.
Explanation:
- Protein can be defined as one of the factors which determine the structure as well as the function of a cell.
- Proteins are composed of polymeric chains of polypeptides, which are made up of amino acid monomers linked to each other by peptide bonds.
- Amino acids can be broadly categorised into non-polar and polar based on the nature of the side chain.
- The non-polar amino acids possess hydrocarbon side-chains which are hydrophobic in nature, so they tend to avoid interaction with water molecules and usually remain in the protein interior. They are uncharged and cannot form any hydrogen bonds with water molecules.
- The polar amino acids possess charged or polar side-chains which are hydrophilic in nature, so they tend to undergo interaction with water molecules and usually remain on the protein surface. They can form hydrogen bonds with molecules of water.
- Beta sheets can be defined a secondary structure of the protein in which the polypeptide sequence forms horizontal strands which are linked to each other by loops. Each strand interact with each other by the formation of hydrogen bonds between the C=O group of one peptide (amide) bond in one strand with the N-H group of another peptide (amide) bond in another strand.
- Apart from these bonds, the non-polar side chains of each amino acid in one strand forms hydrophobic or Van der Waals interactions with the non-polar side chains of each amino acid in the other strand. The polar or charged side chains of the amino acids on each strand form either hydrogen bonds with water molecules or with oppositely charged side chains.
- In the given question, glycine and alanine are non-polar amino acids but serine is a polar amino acid. The side-chains of the non-polar amino acids will tend to face towards the interior of the beta sheet thereby forming hydrophobic interactions with each other, while the serine will tend to face the exterior of the beta sheet so that it can form hydrogen bonds with water molecules.
- As the number of non-polar amino acids is far more than polar amino acids so the effect of non-polar amino acids will prevail in the beta-sheet.
