Which is the smallest plant pathogenic agent?

Which is the smallest plant pathogenic agent?

Viroids are the smallest pathogenic agents yet described. They are single-stranded circular RNA molecules which vary in length from 246 to 463 nucleotides and are found only in plants.

What is the smallest and simplest pathogen?

Viruses are the smallest common pathogen. They are so small in fact that many of them actually infect bacteria. They are different from other pathogens because they cannot reproduce on their own.

What are tiny infectious agents that cause disease?

Viruses are tiny infectious agents that invade host cells and cause disease.

What are the 4 disease agents?

The agents that cause disease fall into five groups: viruses, bacteria, fungi, protozoa, and helminths (worms). Protozoa and worms are usually grouped together as parasites, and are the subject of the discipline of parasitology, whereas viruses, bacteria, and fungi are the subject of microbiology.

Are viroids smaller than mycoplasma?

A step down even from viruses are viroids, which are just naked strands of genetic material—in other words, a virus without the bag. They’re known only to cause diseases in plants, and they can be as small as 10 nanometers (20 times smaller than Mycoplasma).

Is a Virus the smallest organism?

Viruses are the smallest of all the microbes. They are said to be so small that 500 million rhinoviruses (which cause the common cold) could fit on to the head of a pin. They are unique because they are only alive and able to multiply inside the cells of other living things.

How are diseases caused?

Infectious diseases commonly spread through the direct transfer of bacteria, viruses or other germs from one person to another. This can happen when an individual with the bacterium or virus touches, kisses, or coughs or sneezes on someone who isn’t infected.

What is the smallest living organism?

Bacteria
Bacteria, the Smallest of Living Organisms.