Answer:
Option (d).
Explanation:
Mutation may be defined as the sudden, heritable change in the nucleotide sequence of the organism. Mutation may occur due to the errors in DNA replication or may occurs due to the mutagens.
Joshua and Lederberg experiment explains that mutation is the non adaptive and random process that occur in the organism. He used the replica plating of E.coli and grows them on streptomycin drug. The bacteria was grown on the the primary plate and they are transferred to the secondary plate with streptomycin drug in the growth environment. The resistant strain of bacteria grows in the streptomycin environment.The pattern of bacteria growth on the plate explained that mutation occurs randomly and it is a non adaptive process.
Thus, the correct answer is option (d).
Answer:
A change in pH can change the ionization of the side groups of basic and acidic amino acids of proteins., It is important to remember that these charges of are importance in stabilizing a protein secondary and tertiary structure and consequently affects its function. Changing these charges alters these interactions and disturbs protein loops such as beta-sheets and alpha-helices. This can change the structure of a proteins enzyme’s active site and cause it to fail to bind to a substrate or catalyze a reaction.
Beavers are descendants of land-dwelling rodents similar to rats. The beavers however have adapted their body shape to live in water bodies like ponds and lakes. This can be hypothesised by saying that the early rodents or the ancestors of beavers were forced to find food in the waters. They lacked the flat tail and the webbed feet. With time the need to increase their ability to catch fishes and floating insects, the rodents with flatter tail and a bigger flat webbed feet gradually evolved. The rodents with flatter tails and webbed feet became adjusted to the life on water and became the modern day beavers.
I believe it is geographic isolation. Hope it helps.
Answer:
Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed.
Explanation:
