Answer:
Gasoline is a complex blend of compounds made from petroleum. There are various grades of gasoline. Thus it is a mixture. A classmate claims that brass and silver are both pure substances because they have a uniform composition throughout.
Explanation:
Aluminum is a chemical element so it is a pure substance. Thus it is a mixture. Gasoline is a complex blend of compounds made from petroleum
Answer:
The correct answer is - A and D.
Explanation:
Genetic imprinting is DNA modifications that result in changing the expression but not the sequence. Factors That affect such changes present both within and outside the cell.
It is a result of the silencing of either maternal or paternal alleles in a pair. This occurs random and leads to phenomenon like X-inactivation. The mechanism involves methylation of the DNA to be silenced. paternal copy of UBE3A is silenced in neurons.
Groundwater is one of the largest source of water on Earth.
Answer: A. A scientific paper is a reliable source of information.
Explanation:
A peer review is a kind of analysis of the research outcome by the people who generally exhibit the same competency as that of the author or researcher and knowledge for a particular subject or topic in which the research has been conducted. Such a process makes the research outcome more authentic and reliable. The author learns to improvise the research process and corrects the mistakes after the peer review.