Natural selection could not occur without environment, and a act on animal.
Answer:
The correct option is <em>B) ultraviolet region, especially below a wavelength of 320 nm.</em>
Explanation:
Ultraviolet light carries an enormous amount of energy in it. It is invisible to the human eye. When UV light with enormous energy and wavelength lesser than 320nm, hits the DNA, it causes changes in the structure of the DNA. Mostly, it affects the thymine nitrogenous base regions and forms pyrimidine dimers. The structure of the DNA changes on all the sites where dimers form and hence, they cannot be properly transcribed.
Answer:
The correct answer is: c) usually produces offspring that cannot reproduce.
Explanation:
Hybridization, also knowns as selective breeding, is an <u>artificial process</u><u> that involves selecting parents with specific characteristics in order to obtain an offspring with the same traits</u>.
Hybridization is very common and has been performed by humans for thousands of years: from selective breeding crop plants, to do so with dogs in order to create more desirable breeds.
Option A is incorrect because hybridation does not occur in nature, it is an artificial process.
Option B is incorrect because hybridation often happens when the selected parents are chosen to reproduce (by a human).
Option D is correct because an important amount of hybrids are sterile (for example: mules).
Option D is incorrect as well because the offspring is not identical: it shares a combination of genes from both parents.
