A bio-membrane is made up of

Options

A. Protein, lipids and carbohydrates
B. Protein, lipids and RNA
C. Protein, lipids and DNA
D. Protein, lipids and hormones

Explanation

**Step-by-Step Solution:**

1. **Understanding Biomembranes**: A biomembrane is a biological membrane that surrounds cells and organelles. It serves as a barrier and is crucial for maintaining the integrity of the cell.

2. **Components of Biomembranes**: Biomembranes are primarily composed of three types of molecules:
- **Lipids**: The main structural components of biomembranes are phospholipids, which form a bilayer. This bilayer is essential for the membrane's fluidity and flexibility.
- **Proteins**: Various proteins are embedded within the lipid bilayer. These proteins serve multiple functions, including transport, signaling, and structural support.
- **Carbohydrates**: Carbohydrates are often attached to proteins and lipids on the extracellular surface of the membrane, playing a role in cell recognition and communication.

3. **Structure of the Plasma Membrane**: The plasma membrane, also known as the plasma lemma, is a specific type of biomembrane found in all eukaryotic and prokaryotic cells. It consists of a phospholipid bilayer with embedded proteins and associated carbohydrates.

4. **Function of Biomembranes**: The biomembrane's primary function is to regulate the movement of substances in and out of the cell, thus maintaining homeostasis. It also facilitates communication between cells and their environment.

5. **Summary of Components**: To summarize, a biomembrane is made up of:
- Lipids (primarily phospholipids)
- Proteins
- Carbohydrates