Transposable elements are considered to be responsible for vast range of genome diversity and gene silencing.
Explanation:
Transposable elements are short sequences of DNA that have the ability to move from one location to another in the genome. During this process they copy themselves.
The entire process carried out by transposable elements to copy themselves and move from one location to another is called transposition.
Transposition may result in mutation and is potentially a major source of genome diversity and change. If a transposon inserts itself into the coding region of a gene,it interrupts the coding sequence and inactivates the gene expression.
In addition to this, a transposable element may contain transcription or translation termination signal that will block the gene expression downstream of insertion site.
Answer: By studying the fossil record we can tell how long life has existed on Earth, and how different plants and animals are related to each other. Often we can work out how and where they lived, and use this information to find out about ancient environments. Fossils can tell us a lot about the past.
Answer:
La división celular es una parte muy importante del ciclo celular en la que una célula inicial se divide para formar células hijas.1Debido a la división celular se produce el crecimiento de los seres vivos. En los organismos pluricelulares este crecimiento se produce gracias al desarrollo de los tejidos y en los seres unicelulares mediante la reproducción asexual.
Los seres pluricelulares reemplazan su dotación celular gracias a la división celular y suele estar asociada con la diferenciación celular. En algunos animales la división celular se detiene en algún momento y las células acaban envejeciendo. Las células senescentes se deterioran y mueren debido al envejecimiento del cuerpo. Las células dejan de dividirse porque los telómeros se vuelven cada vez más cortos en cada división y no pueden proteger a los cromosomas como tal.
Las células hijas de las divisiones celulares, en el desarrollo temprano embrionario, contribuyen de forma desigual a la generación de los tejidos adultos.
Explanation:
Answer: Option A "Choroid plexus".
Explanation:
Cerebrospinal fluid can be defined as the fluid that is found in the brain and spinal cord of human beings. It is a clear and colorless fluid.
The production of cerebrospinal fluid takes place by the specialized ependymal cells that lies in the choroid plexuses which is present in the ventricles of brain.
The amount of cerebrospinal fluid in a day is 500mL. This fluid acts as cushion that protects the brain from mechanical and immunological protection.
Hence, the correction answer is option A
According to the second law of thermodynamics, energy is never 100% efficient because some of the energy disperses as heat.