Cytoplasm

Cytoplasm is the jelly-like substance that fills the inside of a cell, holding all of the cell’s parts in place. It consists mainly of water and contains proteins, nutrients, and tiny specialized structures called organelles (such as mitochondria, lysosomes, and the nucleus). The cytoplasm is enclosed by a thin protective layer called the cell membrane, which separates the cell’s interior from its surrounding environment.

Why is cytoplasm important?

Cytoplasm is important because it helps the cell carry out essential functions. It provides a stable environment for organelles, allowing them to produce energy, break down waste products, and create new proteins. Cytoplasm also helps cells maintain their shape and structure.

How do pathologists see cytoplasm under a microscope?

Pathologists examine cells under a microscope using special dyes called hematoxylin and eosin (H&E). Hematoxylin stains certain cell parts (like the nucleus) dark blue or purple, while eosin stains the cytoplasm pink. These stains allow pathologists to clearly see the size, shape, and appearance of the cytoplasm, which can help in identifying different cell types and diagnosing diseases.

Does the amount of cytoplasm vary between cells?

Yes, the amount of cytoplasm varies greatly depending on the type of cell. For example, squamous cells on the skin’s surface have a large amount of cytoplasm, giving them a characteristic flat shape. On the other hand, specialized immune cells called lymphocytes have very little cytoplasm and appear smaller and more compact under a microscope.

Common ways pathologists describe cytoplasm:

Pathologists use specific descriptive terms when looking at cytoplasm under a microscope, including:

• Eosinophilic: Cells with eosinophilic cytoplasm look bright pink because they contain a high amount of protein-rich material.

• Oncocytic: Cells with oncocytic cytoplasm appear pink due to having many mitochondria (structures that generate energy) within the cytoplasm.

• Clear: Cells with clear cytoplasm appear transparent because they contain few components that pick up the stains.

• Basophilic: Cells with basophilic cytoplasm appear blue or purple because they contain substances that strongly attract the hematoxylin stain.

Why does the appearance of cytoplasm matter?

The appearance of cytoplasm can provide clues about the type of cell and whether the cell is healthy or diseased. For example, cancer cells often have abnormal-looking cytoplasm, and identifying these changes can help pathologists diagnose cancer and determine the best treatment approach.