Cells Flashcards
Histology
Study of the microscopic structure and function of cells and associated tissue.
Cell
The smallest living unit of organization in the body
Tissue
Cells grouped together with similar characteristics of form and function
Organ
Various tissue types bonded together
System
Organs functioning together
Exocytosis
active transport of material from a vesicle
within the cell out into the extracellular
environment.
Endocytosis
The uptake of materials from the extracellular
environment into the cell
Phagocytosis
Engulfing and then
digesting of solid waste
and foreign material
Cell membrane
Surround the cell
Cytoplasm
The semifluid part contained within the cell membrane boundary as well as the skeletal system of support or
cytoskeleton.
Vacuoles
spaces or cavities in the cytoplasm
Organelles
metabolically active specialized structures within the cell.
Nucleus
The largest, densest, and most conspicuous organelle in the cell
Chromatin
The chief nucleic acid in
the nucleoplasm is
deoxyribonucleic acid
(DNA), in the form of chromatin
DNA
As much as 98% of human DNA does not code for a specific product.
Chromosomes
In an actively dividing cell, the
chromatin condenses into microscopically visible, discrete, rodlike chromosomes
Centromere
Contained in each chromosome. Clear constricted area near the middle
Chromatids
Daughter chromosomes joined by a centromere during cell division.
Nucleoplasm
Fluid part in the nucleus. contains important molecules used in the construction of ribosomes, nucleic acids, and other nuclear materials.
Nuclear Envelope
Surrounds the nucleus. similar the cell membrane by double layered
Nuclear pores
Act as avenues of communication between the inner nucleoplasm and
the outer cytoplasm
Nucleolus
A prominent, rounded nuclear organelle that is centrally placed in the
nucleoplasm
Mitochondria
The most numerous organelles in the cell. They are associated with energy
conversion.
Ribosomes
The tiny sphere-shaped organelles in the cell. produced in the nucleolus from rRNA and protein molecules and are
assembled in the cytoplasm.
Endoplasmic reticulum
(ER)
Consists of parallel membrane bound‑ channels.
Smooth ER
Absence of ribosomes
Rough ER
Rresence of ribosomes
Golgi complex
ER modified protein goes here for subsequent segregation, packaging, and
transport of protein compounds.
Lysosomes
Organelles produced by the Golgi complex and function in both intracellular and extracellular digestion by the cell
Centrosome
A dense, somewhat oval shaped‑ organelle that contains a pair of cylindrical structures, the centrioles.
Cytoskeleton
Three dimensional system of support within the cell
Microfilaments
Consist of specialized proteins. Delicate, threadlike microscopic structures
Microtubules
Consist of specialized proteins. slender, hollow, tubular microscopic structures that may appear
individually, doubly, or as triplets.
Cilia
Shorter and numerous projections on cells
Flagella
Longer and fewer projections on cells
Intermediate filaments
Various types of thicker, threadlike microscopic structures within the cell.
Tonofilaments,
Type of intermediate filament that have a major role in intercellular junctions.
Inclusions
Metabolically inert substances that are also transient over time in the cell.
Cell division
Also known as mitosis. Consists of four phases prophase, metaphase anaphase, and telophase
Tissue Fluid
Provides a medium for dissolving, mixing, and transporting substances and for carrying out chemical reactions.
Intercellular substance
Shapeless, colorless, and
transparent material in which the cells of a tissue are imbedded. fills the spaces between the cells in a
tissue.
Intercellular junctions
Cells in tissues are joined by this mechanism
Desmosome
Superficial layers of the skin or oral mucosa.
Hemidesmosome
Another type of intercellular
junction which involves an attachment of a cell to an adjacent noncellular surface
