Cytology Lecture Two

Processes, packages, and transports proteins and lipids.

Digests cellular waste and foreign matter.

Detoxifies harmful substances and breaks down lipids; Produce hydrogen peroxide.

Double-membraned organelles with cristae; contain own DNA.

Inner space of mitochondria, contains enzymes for energy production.

Membrane-bound vesicle involved in endocytosis and intracellular transport.

Vesicles containing material for digestion; categorized by ingested material.

Circular DNA found in the matrix, inherited maternally.

A thin, flexible barrier that surrounds a cell. It's composed of a phospholipid bilayer with embedded proteins and carbohydrates.

The main structural component of the cell membrane. Two layers of phospholipids arranged with hydrophilic heads facing outward and hydrophobic tails inward.

Proteins embedded within the cell membrane, some extending completely across the membrane (transmembrane).

Proteins that are loosely associated with the cell membrane, often on the inner or outer surface.

Membrane proteins that actively transport substances across the membrane.

Membrane proteins that form channels for passive movement of substances across the membrane.

A sticky carbohydrate-rich covering on the outer surface of the cell membrane, mostly on proteins and lipids.

A lipid component of the membrane that helps maintain its fluidity and stability.

Cells carry out essential processes for survival, growth, and reproduction, including metabolism (absorption, synthesis, respiration, excretion), growth, regeneration, irritability, movement, reproduction, aging, and death.

There are over 250 types of cells, each with specialized shapes and sizes; this variety corresponds to their diverse functions.

Cells range from 5µm to 120µm in diameter.

A eukaryotic cell is made up of three primary components: the cell membrane, cytoplasm, and karyoplasm (nucleus).

Different cells carry out specific tasks, like muscle cells for movement, pancreatic cells for enzyme production, and sensory cells for detecting stimuli.

The human body contains approximately 100 trillion cells.

Cells come in various shapes—round, oval, columnar, and more—reflecting their specialized functions.

The cell membrane is a crucial component of a cell that separates the inside of the cell from the outside.

A yellowish-brown pigment that accumulates in cells as they age, a remnant of lysosomal activity.

A brownish pigment primarily found in skin, hair, and the eyes, responsible for their color. Produced by melanocytes.

Tiny particles of carbon found in macrophages, usually in the lungs, resulting from inhalation.

A yellowish-orange-red pigment obtained from plants, primarily fruits and vegetables.

Crystalline forms of proteins, found in specific cell types. Examples include Reinke crystals in Leydig cells and Charcot-Böttcher crystals in Sertoli cells.

A cylindrical structure composed of four stacked rings, each containing seven proteins, including proteases. It degrades denatured or nonfunctional proteins tagged with ubiquitin.

The control center of the cell, containing genetic material (DNA) and responsible for cell function and reproduction.

Clusters of ribosomes located in the cytoplasm. They synthesize structural proteins and enzymes for use within the cell.

A double membrane surrounding the nucleus, with a space between the membranes called the perinuclear cisternal space.

A complex of DNA and proteins (histones and non-histones) found within the nucleus, responsible for carrying genetic information.

Clusters of ribosomes attached to the outer nuclear membrane and the endoplasmic reticulum (ER). They produce proteins to be secreted or used in other organelles.

A network of protein filaments that provides structure and support to the cell. It includes microtubules, intermediate filaments, and microfilaments.

Hollow tubes made of tubulin proteins. Each microtubule is composed of 13 protofilaments arranged in a cylindrical shape.

Proteins associated with microtubules that help move vesicles and organelles. Examples include kinesin and dynein.

Tough, rope-like fibers that provide structural support for the cell. They are more stable than microtubules or microfilaments.

A type of intermediate filament found in mesenchymal cells, which are derived from mesenchyme, the embryonic tissue that gives rise to connective tissues, muscle, and blood vessels.

A specific intermediate filament found in muscle cells. It strengthens and helps organize the muscle fibers, supporting their contraction and relaxation.

Intermediate filaments found in neurons, the nerve cells. They contribute to the structural integrity of nerve fibers, allowing for efficient signal transmission.

A type of intermediate filament found in glial cells, which support and protect neurons in the nervous system.

Thin, flexible filaments composed of actin protein monomers, arranged in a double helix. They play a vital role in cell movement, muscle contraction, and cell division.

Small, cylindrical structures found in pairs, perpendicular to each other, near the nucleus. Made of microtubules, they control microtubule organization, play a role in cell division, and form the base of cilia and flagella.

Metabolically inactive materials within the cell. Examples include lipid droplets, glycogen granules, pigments, and crystals.