Cytology and Cell Organization

Vocabulary practice flashcards covering cell organization, organelle function, membrane ultrastructure, cell morphology, and cytology fundamentals.

Cytology

The branch of biology and medicine that studies cells, specifically their structure, function, formation, and abnormalities.

Robert Hooke

The botanist who discovered the cell in 1665, coining the term from the Latin "cellula" meaning small chamber.

Anthony van Leeuwenhoek

The scientist who observed animal cells for the first time.

Pap Smear Test

A cytology test used in clinical medicine to screen for cervical cancer.

Prokaryotes

Organisms (identified as bacteria) that lack a membrane-enclosed nucleus and keep their DNA directly in the cytoplasm.

Eukaryotes

Organisms containing a true nucleus—a distinct cellular compartment separated from the cytoplasm that houses DNA.

Viruses (Acaryotes)

Non-cellular entities lacking both a nucleus and cytoplasm that reproduce exclusively by parasitizing a host cell and hijacking its cellular machinery.

Protists

Unicellular eukaryotic organisms, such as protozoa including amoebas and paramecia.

Protoplasm

The complete living content of a cell, which includes the cytoplasm and the nucleus.

Cytoplasm

The cellular contents bounded by the plasma membrane, consisting of the hyaloplasm and morphoplasm (organelles).

Hyaloplasm

A transparent structure serving as a physical support for cellular organelles, composed of the cytosol and the cytoskeleton.

Cytosol

A transparent, homogeneous solution composed of about $80\%$ water, along with proteins, sugars, and ions.

Polygonal Shape

The characteristic cellular shape exhibited by nerve cells.

Prismatic / Cylindrical Shape

The characteristic cellular shape exhibited by intestinal cells.

Rounded Shape

The characteristic cellular shape exhibited by fat cells.

Elongated Shape

The characteristic cellular shape exhibited by muscle cells.

Plasma Membrane Structure

An external cell boundary composed of a double layer of lipids, proteins, and carbohydrates that forms a fluid selective barrier regulating ion and water concentrations.

Organelles

Specialized, membrane-bound structures within cells responsible for carrying out specific cellular activities.

Nucleus

A rounded organelle enclosed by a nuclear envelope that contains nearly all of the cell's DNA and directs growth and division.

Nuclear Envelope

A double-membrane structure consisting of an outer membrane facing the cytoplasm and an inner membrane facing the nucleoplasm, perforated by nuclear pores.

Nuclear Pores

Openings in the nuclear envelope that enable selective molecular exchanges between the nucleus and cytoplasm.

Chromatin

A complex of DNA and proteins that stains intensely with basic dyes, present during interphase and condensing into chromosomes during division.

Nucleolus

An intranuclear structure serving as a reservoir of materials for ribosomal assembly, which disappears during nuclear division.

Nucleoplasm

The intranuclear fluid containing precursors required for DNA synthesis and RNA messengers traveling to the cytoplasm.

Rough Endoplasmic Reticulum (RER)

A system of flattened membrane cavities bearing surface-attached ribosomes involved in protein synthesis and processing.

Ergastoplasm

The name given to highly developed rough endoplasmic reticulum found in certain specialized cells.

Smooth Endoplasmic Reticulum (SER)

An endoplasmic reticulum system devoid of ribosomes that functions in lipid synthesis, drug detoxification, and calcium storage.

Ribosomes

Granular structures located free in the cytosol or attached to the RER and nuclear envelope that synthesize proteins.

Golgi Apparatus

A membrane organelle formed by stacked flattened sacs (cisternae) that modifies, matures, and packages proteins received from the RER for secretion or transport.

Cisternae

Flattened membrane sacs that form the structural stacks of the Golgi apparatus.

Lysosomes vs Peroxisomes

Lysosomes are animal cell organelles containing lytic enzymes for cellular digestion; peroxisomes break down fatty acids and alcohol via $\beta$-oxidation and manage hydrogen peroxide.

Neuron Structure

A specialized cell structure featuring a central cell body with a nucleus, extending dendrites, and an axon wrapped in myelin sheath ending at axon terminals.