Genetic markers that distinguish a self cell from a foreign invader are typically...

Genetic markers that help to differentiate self cells from foreign invaders, such as pathogens, are primarily composed of proteins or glycoproteins. These markers are often found on the surface of cells as part of molecules known as major histocompatibility complex (MHC) proteins. MHC molecules play a crucial role in the immune system by presenting antigens (which are pieces of foreign proteins) to T cells, helping the body recognize what is self and what is non-self.

The reason proteins and glycoproteins are significant is that they can have a diverse range of structures and functions, allowing the immune system to identify and respond to a vast array of different pathogens. This diversity is essential for effective immune surveillance and response.

While carbohydrates, lipids, and nucleic acids can play roles in cellular function and signaling, they do not serve as primary markers for self versus non-self identification in the immune response. Carbohydrates can be involved in cell recognition but are usually part of glycoproteins or glycolipids. Lipids generally contribute to membrane structure and signaling rather than serving as identity markers. Nucleic acids are mainly involved in genetic information storage and processing and do not typically function in the same role as proteins in cell recognition