EVERYDAY SCIENCE

Detailed explanation-1: -Viruses typically have spherical (polyhedral), rod-shaped, or helically shaped capsids. Some viruses, such as bacteriophages, have complex shapes which include the addition of a protein tail attached to the capsid with tail fibers extending from the tail. Viruses are much smaller than bacteria.

Detailed explanation-2: -Some viruses have an external membrane envelope. Viruses are very diverse. They come in different shapes and structures, have different kinds of genomes, and infect different hosts.

Detailed explanation-3: -They come in four basic shapes: spherical (cocci), rod-shaped (bacilli), arc-shaped (vibrio), and spiral (spirochete) (Figure 1.3(A)). Figure 1.3. (A) Basic shape of bacteria.

Detailed explanation-4: -Individual bacteria can assume one of three basic shapes: spherical (coccus), rodlike (bacillus), or curved (vibrio, spirillum, or spirochete). Considerable variation is seen in the actual shapes of bacteria, and cells can be stretched or compressed in one dimension.