Cell recognition and adhesion are facilitated by components of plasma membrane. These components are generally

Options

A. protein molecules alone
B. lipids alone
C. both lipids and proteins
D. glycolipids and glycoproteins.

Explanation

**Step-by-Step Solution:**

1. **Understanding Cell Recognition and Adhesion:**
- Cell recognition and adhesion are crucial processes that allow cells to identify and interact with each other. This is essential for various biological functions, including immune responses and tissue formation.

2. **Components of the Plasma Membrane:**
- The plasma membrane is composed of various molecules, primarily lipids and proteins. These components play significant roles in cell recognition and adhesion.

3. **Role of Proteins:**
- Proteins in the plasma membrane, particularly glycoproteins, are vital for cell recognition. They serve as identity markers that help the immune system distinguish between self-cells (the body's own cells) and foreign cells (such as pathogens).

4. **Role of Glycolipids:**
- Glycolipids, which are lipids with carbohydrate chains, also contribute to cell recognition and adhesion. They can interact with proteins and other cells, facilitating communication and attachment.

5. **Conclusion:**
- Both glycoproteins and glycolipids are essential components of the plasma membrane that facilitate cell recognition and adhesion. Therefore, the correct answer to the question is that these components are generally both lipids and proteins.

**Final Answer:**
Cell recognition and adhesion are facilitated by components of the plasma membrane, which are generally both lipids and proteins.

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