The structure of DNA is double helix which looks like twisted ladder. The sides of the DNA molecule, the rails of the ladder are composed of alternate phosphate and sugar molecules.
Crop modification is when the DNA of a plant is altered, commonly used to make them more desirable. For example, bananas weren’t always these long and seedless fruits but with crop modification, over time scientists were able to change the DNA of the banana we know today.
The correct answer is C. Virus.
Virus falls on the gray area which is between nonliving and living things.
Virus is referred to as the small infectious agent which replicates only inside the living cells. Virus can infect life forms plants and animals and microorganisms, for example, archaea and bacteria.
They live in form of independent particles which are referred to as virions. Some viruses can evolve from plasmids.
Endosymbiotic prokaryotes.
The correct option is B.
The alimentary canal is the pathway through which ingested foods move from the mouth all through into the anus. At each portion of the canal, different types of chemical reactions take place, which digest the eaten food and prepare the useful part for absorption and the waste part for excretion. In the alimentary canal, the stomach open into the small intestines. The small intestines is the site where the useful part of the nutrients will be absorbed into the system through villi.
