Question

1. viral spikes

are present in all viruses
are made of lipids
attach specifically to host cell receptors
attach nonspecifically to host cell receptors

1. in viral entry by endocytosis

the host cells plasma membrane surrounds the whole virion and forms a vesicle
viral spikes fuse with the host cells plasma membrane to form a vesicle
the host cells plasma membrane surrounds only the viral protein - acid coat and forms a vesicle
the host cells plasma membrane surrounds only the viral nucleic acid coat and forms a vesicle

1. both enveloped and naked viruses can enter a cell by endocytosis (true or false)
2. a naked virus fuses with the host cell membrane.

Explanation:

1. Viral spikes are not present in all viruses. They are made of proteins and specifically attach to host - cell receptors to initiate infection.
2. In viral entry by endocytosis, the host cell's plasma membrane surrounds the whole virion and forms a vesicle.
3. Both enveloped and naked viruses can enter a cell by endocytosis. A naked virus does not fuse with the host - cell membrane in the same way as an enveloped virus during entry by endocytosis.

Answer:

1. attach specifically to host cell receptors
2. the host cell's plasma membrane surrounds the whole virion and forms a vesicle
3. True
4. False