Chapter 3 Outline - Cell Biology Vocabulary Flashcards

Vocabulary practice flashcards generated directly from Chapter 3 cell biology lecture notes covering cell structures, membrane transport, organelle functions, genetic expression, division, and clinical imbalances.

Cytology

The study of cell structure and function, also known as cell biology.

Plasma membrane

A flexible, sturdy barrier that surrounds and contains the cytoplasm of the cell.

Fluid mosaic model

A structural model describing the plasma membrane as a moving sea of lipids containing various membrane proteins.

Lipid bilayer

The basic framework of the plasma membrane, consisting of two back-to-back layers made up of phospholipids, cholesterol, and glycolipids.

Amphipathic

Molecules having both polar (charged, hydrophilic) and nonpolar (uncharged, hydrophobic) parts.

Integral proteins

Membrane proteins that extend into or across (transmembrane) the entire lipid bilayer among the fatty acid tails of the phospholipid molecules.

Peripheral proteins

Membrane proteins located at the inner or outer surface of the membrane that can be stripped away without disturbing membrane integrity.

Glycocalyx

A pattern formed by the carbohydrate portions of glycolipids and glycoproteins that helps cells recognize and adhere to one another and protects them from extracellular enzymes.

Aquaporins

Transmembrane proteins embedded within the plasma membrane that function as selective channels for water molecules.

Concentration gradient

The difference in the concentration of a chemical between one side of the plasma membrane and the other.

Membrane potential

An electrical gradient set up by a higher concentration of negative charges on the inner surface of the membrane and positive charges on the outer surface.

Electrochemical gradient

The combined influence of the concentration gradient and the electrical gradient across the plasma membrane.

Diffusion

The random mixing of particles in a solution as a result of their kinetic energy.

Simple diffusion

A passive process in which nonpolar, hydrophobic molecules move across the lipid bilayer without the help of transport proteins.

Osmosis

The net movement of a solvent (water) through a selectively permeable membrane from an area of higher water concentration to an area of lower water concentration.

Tonicity

A measure of a solution's ability to change the volume of cells by altering their water content.

Isotonic solution

A solution in which body cells maintain their normal shape and volume.

Hypotonic solution

A solution with a lower solute concentration than the inside of cells, causing red blood cells to undergo hemolysis.

Hypertonic solution

A solution with a higher solute concentration than the inside of cells, causing red blood cells to undergo cremation.

Primary active transport

An active process in which energy derived from the hydrolysis of ATP changes the shape of a transporter protein to pump a substance across the plasma membrane against its concentration gradient.

Secondary active transport

An active process in which energy stored in a sodium or hydrogen ion concentration gradient is used to drive other substances against their own concentration gradients.

Phagocytosis

A form of endocytosis in which specialized cells called phagocytes (macrophages and neutrophils) ingest solid particles.

Pinocytosis

A form of endocytosis involving the nonselective ingestion of extracellular fluid, also known as bulk phase endocytosis.

Exocytosis

A transport process in which membrane-enclosed secretory vesicles formed inside the cell fuse with the plasma membrane to release contents into the extracellular fluid.

Transcytosis

An active transport process that combines endocytosis and exocytosis to move a substance successively into, through, and out of a cell.

Cytosol

The semifluid portion of the cytoplasm containing water, dissolved solutes, and inclusions where many metabolic reactions occur.

Microfilaments

The thinnest elements of the cytoskeleton, mostly composed of actin, that function in movement and mechanical support.

Intermediate filaments

Cytoskeletal elements composed of several proteins that provide structural support and help anchor organelles such as the nucleus.

Microtubules

Long, unbranched hollow tubes composed of tubulin that help determine cell shape and function in intracellular transport and chromosome migration during cell division.

Centrosomes

Dense areas of cytoplasm containing paired centrioles arranged at right angles that serve as centers for organizing microtubules and the mitotic spindle.

Cilia

Numerous short, hairlike projections extending from the cell surface that move materials across the cell's surface.

Flagella

Long projection extending from a cell surface that functions to move an entire cell, with the sperm tail being the only human example.

Ribosomes

Tiny organelles consisting of ribosomal RNA and proteins that function as the sites of protein synthesis.

Rough ER

Endoplasmic reticulum continuous with the nuclear membrane and studded with ribosomes on its outer surface.

Smooth ER

Endoplasmic reticulum extending from the rough ER lacking ribosomes, involved in lipid synthesis, fatty acid synthesis, detoxification, and calcium ion storage.

Golgi complex

An organelle composed of 4 to 6 stacked, flattened membranous sacs (cisterns) that processes, sorts, and delivers proteins and lipids.

Lysosomes

Membrane-enclosed vesicles containing digestive enzymes that perform intracellular digestion, autophagy, and autolysis.

Autophagy

The digestion of worn-out organelles by lysosomal enzymes.

Autolysis

The destruction of an entire cell by its own lysosomal enzymes during embryological development or tissue injury.

Peroxisomes

Small, membrane-enclosed organelles containing oxidase enzymes like catalase that utilize molecular oxygen to neutralize organic substances.

Proteasomes

Tiny structures containing proteases that continually degrade unneeded, damaged, or faulty proteins.

Mitochondria

Double-membrane organelles with internal cristae folds that produce ATP through nutrient catabolism and play a key role in apoptosis.

Nucleoli

Non-membrane enclosed clusters of protein, DNA, and RNA located inside the nucleus that function in producing ribosomes.

Transcription

The process by which genetic information in DNA is copied onto a strand of RNA to direct protein synthesis.

Translation

The process in which mRNA nucleotide sequence is read at a ribosome to specify the amino acid sequence of a protein.

Introns

Regions within a gene that do not code for parts of proteins.

Exons

Regions within a gene that code for functional segments of a protein.

Apoptosis

Genetically programmed cellular death triggered from outside or inside the cell ('cell-suicide').

Necrosis

Pathological cell death resulting from tissue injury.

Metastasis

The spread of cancerous cells from a primary tumor to other parts of the body.

Angiogenesis

The growth of new networks of blood vessels triggered by malignant cancer cells.

Carcinogen

A chemical agent or form of radiation that causes cancer by inducing mutations in cellular DNA.

Oncogenes

Cancer-causing genes mutated from normal cellular counterparts known as proto-oncogenes.