Answer:
The correct answer is a mantle.
Explanation:
A mantle refers to an essential component of the body of molluscs. It refers to a delicate covering produced from the body wall that at certain occasions get strengthened by calcium carbonate.
In various species of molluscs, the epidermis of the mantle discharges calcium carbonate and produces a shell over the entire body. The mantle encloses the stomach, heart, gonads, and intestines of the molluscs.
Answer:
This question lacks options, options are: A) Heterochromatin and euchromatin
B) Uniform in the genetic information they contain
C) Separated by large sketches of repetitive DNA
D) Each void of typical protein-coding sequences of DNA
E) Void of introns.
The correct answer is A.
Explanation:
The chromatin or substance that makes up the nuclei of cells and that results from the interaction of DNA with histonic and non-histonic proteins and RNA; it can present different degrees of packing or contraction. When chromosomes are stained with chemicals that bind to DNA, densely stained regions and less densely stained regions appear. Heterochromatin are segments of the chromosome that stain strongly and remain visible, practically, during the entire cell cycle. There are few genes in these regions and therefore low transcriptional activity. They are supercondensed regions. Euchromatin are segments of the chromosome that are not visible during telophase and interphase, only in metaphase. It corresponds to regions that are less compact and in which there is a higher gene density.
