This histological image shows a section of respiratory epithelium, illustrating the ciliated pseudostratified columnar epithelium found in the trachea and upper respiratory tract. Each labeled component plays a specific role in maintaining respiratory health: 1. **Cilia**: These hair-like structures extend from the surface of ciliated cells. Their primary function is to move mucus and trapped particles out of the respiratory tract. 2. **Goblet Cell**: These are specialized epithelial cells responsible for secreting mucus. Mucus serves to trap dust, pathogens, and particles, preventing them from reaching deeper parts of the respiratory system. 3. **Basal Cell**: These cells act as progenitor cells, capable of dividing and differentiating into other types of epithelial cells, playing a critical role in the repair and regeneration of the epithelium. 4. **Basement Membrane**: This thin, fibrous layer underlies the epithelium, providing structural support and anchoring the epithelial cells to connective tissue. 5. **Lamina Propria**: The layer of connective tissue beneath the epithelium. It contains blood vessels, nerves, and immune cells essential for nutrient exchange and defense mechanisms. The image provides a detailed visualization of healthy respiratory epithelium, essential for both understanding normal airway function and recognizing pathological changes in respiratory diseases. The image showcases a dissected human eyeball with various parts labeled for educational purposes: 1. **Cornea and Sclera**: The outermost layer of the eye is visible. The cornea is transparent and prominently positioned, while the sclera is the white part surrounding it. 2. **Pupil and Iris**: Visible at the center of the eye. The pupil appears as a dark circle, surrounded by the iris, which is often colored. 3. **Aqueous Humor**: The fluid-filled space between the cornea and the lens area is indicated, although not directly visible in the image. 4. **Lens**: Positioned behind the pupil and iris, the lens appears transparent and is responsible for focusing light onto the retina. 5. **Retina and Choroid**: The back of the eye is highlighted, showing layers responsible for receiving light and housing blood vessels. 6. **Optic Nerve**: This is indicated at the back, which transmits visual information from the retina to the brain. The dissection reveals the internal structure of the eye, providing insights into the components involved in the human visual system.