Answer:
d
Explanation:
<em>Crossing over shuffles alleles on non-sister chromatids of homologous chromosomes.</em>
At the prophase I stage of meiosis, homologous chromosomes synapsed to form a four-chromatid structure known as tetrad. Exchange of chromosomal segments between non-sister chromatids of the tetrad then takes place, a process that results in the reshuffling of genes or alleles on the non-sister chromatids.
Hence, none of the answers is correct.
Correct option: d
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.
Starfish: invertebrates
Amphibians: vertebrates
Birds: vertebrates
Octopus: invertebrates
Coral: invertebrates
Fish: vertebrates
Clam: invertebrates
Reptiles: vertebrates
