Membrane envelope

Definition

A membrane envelope is a lipid bilayer that surrounds some viruses, providing an extra layer of protection and aiding in the infection of host cells. It often contains viral proteins that help the virus attach to and enter host cells.

5 Must Know Facts For Your Next Test

1. The membrane envelope is derived from portions of the host cell membranes (lipid and proteins) but includes some viral glycoproteins.
2. Enveloped viruses are typically more sensitive to environmental factors such as detergents and desiccation compared to non-enveloped viruses.
3. Membrane envelopes play a crucial role in the entry of viral particles into host cells by facilitating fusion with the host cell membrane.
4. Examples of enveloped viruses include Influenza virus, HIV, and Herpes simplex virus.
5. The presence of a membrane envelope can affect the immune response, as it may help the virus evade detection by the host's immune system.

Review Questions

Related terms

Capsid:

The protein shell that encloses the viral genome.

Glycoprotein: Proteins with carbohydrate groups attached, found on the surface of some viruses including enveloped ones.

Lipid Bilayer:

A thin polar membrane made of two layers of lipid molecules; foundational structure for biological membranes including viral envelopes.