La manipulación genética representa todas aquellas técnicas que permiten modificar de forma directa los genes en el interior de las células de los organismos vivos. Estas modificaciones pueden ser a través de la inserción, la eliminación o la alteración de uno o más genes específicos. Todas las instrucciones que hacen que un organismo sea lo que es están codificadas en los genes, es decir que estos fragmentos de ADN son los que le indican a cada parte de las células y a cada célula en el cuerpo de un organismo multicelular o unicelular, qué debe hacer, cuándo y cómo. La manipulación genética es uno de los procesos científicos biotecnológicos más empleados hoy en día, ya que incluye todas las herramientas necesarias para modificar las características físicas de prácticamente cualquier ser vivo o, mejor dicho, de todo lo que tenga información genética en su interior (ADN o ARN).
Hoy en día la manipulación genética es uno de los temas más discutidos por la sociedad científica, pues existen herramientas biotecnológicas capaces de manipular de manera fácil y efectiva casi cualquier gen que se desee en un organismo Entre los organismos que se pueden “manipular genéticamente” se incluye al ser humano, y es allí donde surgen la mayoría de los debates, ya que a pesar de que la manipulación genética puede ayudar a curar un gran número de enfermedades hereditarias, también puede utilizarse para crear armas biológicas sumamente peligrosas.
The question is incomplete. The complete question is as follows:
Which of the following mutations is most likely to cause a phenotypic change?
A) a duplication of all or most introns
B) a large inversion whose ends are each in intergenic regions
C) a nucleotide substitution in an exon coding for a transmembrane domain
D) a single nucleotide deletion in an exon coding for an active site
E) a frameshift mutation one codon away from the 3' end of the nontemplate strand
Answer: D) a single nucleotide deletion in an exon coding for an active site
Explanation:
Deletion or insertion of a single nucleotide in an axon coding for an active site is called frameshift mutation.
The sequence of codons is read during translation, in order to synthesize a amino acids chain and form a protein from the nucleotide sequence. Frameshift mutations occur when the usual codon sequence is broken by the deletion or addition of one or more nucleotides. For example, if only one nucleotide is removed from the axon sequence during the RNA splicing process, then there will be a disrupted reading frame for all codons before and after the mutation. This may result in several incorrect amino acids being introduced into the protein. Disruption in protein sequence will cause phenotypic change.
Hence, the correct option is D) a single nucleotide deletion in an exon coding for an active site
.
A nucleotide is DNA
(Also RNA)
Hope that helped! :)
Explanation:
Chloroplast is the correct answer
Answer:
Neurons, as with other excitable cells in the body, have two major physiological properties: irritability and conductivity. A neuron has a positive charge on the outer surface of the cell membrane due in part to the action of an active transport system called the sodium potassium pump. This system moves sodium (Na+) out of the cell and potassium (K+) into the cell. The inside of the cell membrane is negative, not only due to the active transport system but also because of intracellular proteins, which remain negative due to the intracellular pH and keep the inside of the cell membrane negative.
Explanation:
Neurons are cells with the capacity to transmit information between one another and also with other tissues in the body. This information is transmitted thanks to the release of substances called <em>neurotransmitters</em>, and this transmission is possible due to the <em>electrical properties </em>of the neurons.
For the neurons (and other excitable cells, such as cardiac muscle cells) to be capable of conducting the changes in their membranes' voltages, they need to have a<em> resting membrane potential</em>, which consists of a specific voltage that is given because of the electrical nature of both the inside and the outside of the cell. <u>The inside of the cell is negatively charged, while the outside is positively charged</u> - this is what generates the resting membrane potential. When the membrane voltage changes because the inside of the cell is becoming less negative, the neuron is being excited and - if this excitation reaches a threshold - an action potential will be fired. But how does the voltage changes? This happens because the distribution of ions in the intracellular and extracellular fluids is very dissimilar and when the sodium channels in the cell membrane are opened (because of an external stimulus), sodium enters the cell rapidly to balance out the difference in this ion concentration. The sudden influx of this positively-charged ion is what makes the inside of the neuron become less negative. This event is called <em>depolarization of the membrane</em>.
