Biology Questions

August Weismann cut off the tails of mice for 21 successive generations and still they produced generation after generation of only tailed young ones. So he concluded that acquired characters are not inherited.

The correct statement from the given options is

The AV valves are supported by chordae tendineae so that regurgitation of blood into the atria during ventricular contraction does not occur.

Leukorrhea is a thick, whitish or yellowish vaginal discharge. There are many causes of leukorrhea, the usual one being estrogen imbalance. The amount of discharge may increase due to vaginal infection or STDs, and it may disappear and reappear from time to time. This discharge can keep occurring for years, in which case it becomes more yellow and foul-smelling. It is usually a non-pathological symptom secondary to inflammatory conditions of vagina or cervix.

In the cell, transcription occurs in the nucleus in the presence of DNA.

Terms transcription and translation in biology are generally related to the DNA and its properties. Human cells replicate. In order to do that, they have to produce the same constituents for the new cell that is to be made. The only way to do that is by producing proteins.

The proteins are produced in the process that is called protein synthesis. The first step is in the nucleus where a particular gene is being expressed so it enables all protein factors to come and to replicate that part of a chromosome. This is finished when mRNA, the same single-stranded genetic code of a particular gene, is formed. This is transcription.

Right after that, the mRNA enters the cytoplasm through nuclear pores. There, it could be translated into proteins by ribosomes. This process is called translation.

Hence, Transcription occurs in the nucleus, whereas translation occurs in the cytoplasm.