Why do woollen clothes keep us warm in winter?
Wool is a good conductor of heat.
Wool traps heat effectively between its layers.
Wool is a bad conductor of heat.
Wool produces its own heat from its layers.
During isolation of genetic material, the chemical used to precipitate out the purified DNA is
bromophenol blue
chilled ethanol
ethidium bromide
both a and c
Explanation: Chilled ethanol is used to precipitate DNA during the isolation of the target gene as it readily gathers clusters of tiny threads in suspension.
Magnetic separation is used if either the ore or the impurity is magnetic. As iron has magnetic properties and can be attracted by a magnet we can use magnetic separation for the concentration of iron ore.
Every complete sentence contains two parts: a subject and a predicate. The subject is what (or whom) the sentence is about. The predicate tells something about the subject. The predicate of the sentence contains the verb.