Cytology Lecture 1 Quiz

Cell Membrane and Cellular Compartments

• The cell membrane, also known as the plasma membrane, serves as a selective barrier, regulating the movement of substances in and out of the cell.
• The cell consists of two main compartments: the cytoplasm and the nucleus.

Histology and Microscopy

• The main focus of histology is the study of the structure and organization of cells and tissues.
• The electron microscope is capable of visualizing the cell membrane, which is too thin to be seen with a light microscope.

Cell Membrane Specializations

• Microvilli are cell membrane specializations that increase the surface area of absorptive cells in the small intestine, allowing for more efficient nutrient absorption.
• Cilia are cell membrane specializations that push away mucus and harmful materials in certain parts of the respiratory tract.
• Flagella are longer and present only in spermatozoa, responsible for their movement.

Cell Junctions

• Tight junctions connect adjacent cells together by fusing their outer layers and having an absent intercellular space.
• Gap junctions connect adjacent cells together and allow for direct communication between them, enabling the exchange of ions, nutrients, and waste products.
• Desmosomes connect adjacent cells together and have a narrowing of the intercellular space between them.

Cellular Structure and Function

• The cell is the smallest structural and functional unit in the human body.
• The main function of gap junctions is to facilitate direct communication between adjacent cells, allowing for the exchange of ions, nutrients, and waste products.