One of the most unusual aspects of virus particles is the absence of all organelles and other smaller structures. Whereas cells have many kinds of organelles, viruses consist of only two parts: a nucleic acid core made of DNA or RNA, and a tough, potective protein shell. Which name is given to this tough shell made of protein?

The protein covering of a virus is called a capsid.

integrated circuit (ic) is defined as a set of electronic circuits on one small flat piece of semiconductor material, normally silicon. a functional electronic circuit requires transistors, resistors, capacitors, inductors, etc., and the connections between them.

1) gene flow

- it is described as the transfer of genes from one population to another population so that frequency of gene is increased.

-a zebra migrates to join a different herd of zebras.

2) natural selection

- a mechanism of evolutionary change in which individuals with advantageous traits survive and reproduce whereas the others ( those that can not adapt) eliminate from the population.

-competition for sunlight leads to taller trees.

3) mutation

- permanent change in the nucleotide sequence of dna ( genetic material) that could have harmful or useful consequences.

-the dna of a snake changes to make its venom stronger.

4) genetic drift - it is a random phenomenon ( that occurs by chance such as fire) that results in change in the gene frequency in a small population.    

-a grassfire randomly sweeps through a population of buffalo and kills most of the animals.

explanation: