Question

label the photomicrograph of the sebaceous gland.
basal cell
duct of sebaceous gland
hair follicle
sebaceous gland
secretory cell

Explanation:

To label the photomicrograph of the sebaceous gland, we analyze each structure:

1. Hair follicle: The outermost purple - lined structure with a lumen (the white central part) is the hair follicle. It is a sheath that encloses the hair root.
2. Duct of sebaceous gland: The narrow connection between the hair follicle and the sebaceous gland is the duct. It carries the secretions from the gland to the hair follicle.
3. Basal cell: The cells at the base of the sebaceous gland (near the duct) with a more compact appearance (darker staining in some cases, though here the basal cells are at the periphery of the glandular acini, adjacent to the duct) are the basal cells. They are responsible for cell division and renewal of the gland.
4. Sebaceous gland: The clustered glandular structures (the pinkish - purple acini) attached to the hair follicle via the duct are the sebaceous glands. They are responsible for producing sebum.
5. Secretory cell: The larger, more centrally located cells within the sebaceous gland acini are the secretory cells. They are filled with lipid - rich material (sebum) and are responsible for secretion.

Assuming the labels are from top to bottom (matching the order of the lines in the photomicrograph):

• Top line: Hair follicle
• Second line: Duct of sebaceous gland
• Third line: Basal cell
• Fourth line: Sebaceous gland
• Fifth line: Secretory cell

Answer:

Top to bottom (matching the order of the labeling lines):

1. Hair follicle
2. Duct of sebaceous gland
3. Basal cell
4. Sebaceous gland
5. Secretory cell