Biology Questions

Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations.

Translation occurs in the cytoplasm whereas transcription occurs in the nucleus.

Transcription and Translation:

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.

Cretinism is a disease caused by hypothyroidism (less thyroxine formation) . The symptoms of the disease are retardation of mental, physical and sexual developments. potbelly, protruding tongue, dry skin etc are also indicative of this disease.

The hormone adrenaline also called epinephrine is known as a stress harmone. In emotional upset (like fear, anger etc.) this harmone is poured into the blood and it accelerates heart beat. The hormone acetylcholine decelerates heartbeat rate.