<span>Human genetic disorders can be caused largely by the change of the DNA sequence from its normal sequence. This can also be caused by a monogenic disorder, a mutation in a gene. So the best answer to this question would be letter B since nondisjunction causes chromosomal abnormalities.</span>
        
             
        
        
        
Explanation:
Scientists didnt belive that there are cells untill robert hooke (1665). He observed the cells in a cork slice with the help of a PRIMITIVE microscope
Leeuwenhoek (1674), with the help of an improved microscope, discovered free living cells in pound water for the first time. 
It was robert brown in (1831) who discovered the nucleus in the cell. 
Purkinjie in 1839 coined the term 'protoplasm' for the fluid substance of the cell. 
THE CELL THEORY, that all plants and animals are composed of cells and that the cell is the basic unit of life, was presented by two biologists, schleiden (1838) and schwann(1839). The cell theory was fuether expanded by virchow (1855) by suggesting that all cells aris form PRE-EXISTING cells. With the discovery of the electron microscope in 1940,it was possible to observe and understand the complex structure of the cell and its various organelles. 
Well, thats the history of the discovery of cells. 
 
        
             
        
        
        
Answer:
Its used as validity, and quality of the articles. The main purpose of it is to filter out poor or invalid articles.
Explanation:
 
        
             
        
        
        
Answer:
Sensory transduction.
Explanation:
Sensory transduction may be defined as the process by which sensory stimulus are transformed in the body. The receptor cell is mainly involved in the sensory transduction process.
The sensory receptor cell like a light or an odor is converted into the electrical signal by the process of signal transduction. The information is then conveyed to the nervous system in the form of electrical signals.
Thus, the correct answer is signal transduction.