Cell Structure and Function

Vocabulary flashcards covering cellular organization, organelle structure, and physiological functions based on lecture notes.

Physiology

The science of life and the study of how living organisms function and survive in continuously changing environments.

Cell

The building block of the human body and the basic functional and structural unit of living tissues.

Cell/Plasma Membrane

A selectively permeable complex barrier formed of lipids, proteins, and carbohydrates that defines the periphery of the cell, provides shape, and protects inner contents.

Cytoplasm

The cellular content consisting mostly of water, metabolites, enzymes, coenzymes, and inorganic ions ($K^+$, $Na^+$, $Mg^{2+}$, $Ca^{2+}$) that acts as a supportive medium for organelles.

Nucleus

The control center of cellular activities and storehouse of the cell's DNA, responsible for replication, transcription, and carrying chromosomes.

Cytoskeleton

A network of non-membrane bound filaments that maintains constant cell shape, provides mechanical resistance against deformation, and aids in motility and cell division.

Mitochondria

Double membrane-bound organelles known as the powerhouse of the cell, responsible for ATP production, matrix catabolic pathways, and initiating apoptosis via Cytochrome C.

Cristae

Folds formed by the inner membrane of mitochondria that provide a larger surface area.

Apoptosis

Programmed cell death, initiated in part by the Cytochrome C component of mitochondria.

Rough Endoplasmic Reticulum (RER)

Endoplasmic reticulum studded with ribosomes to give a granular appearance, playing a major role in protein synthesis.

Smooth Endoplasmic Reticulum (SER)

Endoplasmic reticulum devoid of ribosomes that acts as an intracellular highway and serves as the site for lipoprotein, glycoprotein, lipid, steroid, and membrane synthesis.

Sarcoplasmic Reticulum

A specialized smooth endoplasmic reticulum in muscle cells that stores and releases calcium ions needed for muscle contraction.

Golgi Apparatus

A membrane system composed of flattened saclike cisternae and vesicles that completes the work of the ER through processing, packaging, sorting, and maturation of synthesized proteins.

Cisternae

Flattened saclike membrane structures that constitute the Golgi apparatus.

Lysosomes

Spherical single membrane-bounded vesicles containing hydrolytic enzymes (hydrolases) capable of digesting proteins, polysaccharides, lipids, nucleic acids, nutrients, viruses, and bacteria.

Ribosomes

Non-membrane bound cytoplasmic organelles, found free or in close association with the endoplasmic reticulum, that function in protein synthesis.

Peroxisomes (Microbodies)

Small membrane-bounded vesicles containing enzymes like catalase involved in detoxification, $\beta$-oxidation of very-long-chain fatty acids, ROS neutralization, and amino acid and purine metabolism.