Answer:
a virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism.[1] Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea.[2][3] Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898,[4] more than 9,000 virus species have been described in detail[5] of the millions of types of viruses in the environment.[6] Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity.[7][8] The study of viruses is known as virology, a subspeciality of microbiology.
Answer: However, during exercise, many other muscles become important to respiration. During inspiration, the external intercostals raise the lower ribs up and out, increasing the lateral and anteroposterior dimensions of the thorax.
Active absorption :- It is a up stream absorption in which use of specified Protein along with ATP is used to absorb substance like ions etc. Active absorption occur against the concentration gradient
Facilitated diffusion :- It is a down stram absorption in which use of special protein is there but no ATP is used to absorb substance like water in plant cell . Facilitated diffusion occur through concentration gradient
Diffusion :- It is a down stream absorption in which no requirement of special protein and ATP molecules is there to absorb substance like glucose etc . Diffusion occur through concentration gradient.
