Cellular Biology Review - Lecture Notes (VOCABULARY Flashcards)

A vocabulary set of key terms and definitions covering cell properties, membranes, transport, signaling, signaling, and basic cell division concepts from the lecture notes.

Cell

The basic functional unit of life; carries out essential cellular processes such as homeostasis, growth, metabolism, absorption, secretion, irritability, conductivity, and contractility.

Homeostasis

Tendency of living systems to maintain a stable internal state.

Hypertrophy

Increase in the size of existing cells as an adaptive growth change.

Hyperplasia

Increase in the number of cells, leading to tissue or organ growth.

Reproduction (cell)

Production of more cells or organisms that are essentially the same as the original cell.

Absorption

Uptake of dissolved materials or water through the cell membrane; can be passive or active.

Metabolism

Sum of physical and biochemical reactions occurring in a cell.

Secretion

Production and discharge of substances from a cell or gland; involves exocytosis.

Irritability

Ability to react to a stimulus (also called excitability).

Conductivity

Transmission of an electrical impulse within a cell.

Contractility

Ability of a cell to shorten or lengthen.

Plasma membrane

Outer cell membrane (cell boundary) composed primarily of phospholipids, proteins, and cholesterol.

Phospholipid bilayer

Two-layer arrangement of phospholipids with hydrophilic heads outward and hydrophobic tails inward.

Integral protein

Membrane protein embedded through the lipid bilayer.

Peripheral protein

Membrane protein attached to the surface of the membrane.

Glycoprotein

Membrane protein with carbohydrate chains involved in transport and signaling.

Glycolipid

Lipid with carbohydrate groups involved in cell recognition.

Cholesterol

Sterol within the membrane that modulates fluidity and stability.

Transmembrane protein

Protein spanning the membrane; facilitates transport and signaling.

Osmosis

Diffusion of water across a semipermeable membrane.

Diffusion

Movement of molecules from high to low concentration (includes simple and facilitated diffusion).

Facilitated diffusion

Diffusion aided by specific transport proteins without energy use.

Active transport

Energy-dependent movement of substances against their concentration gradient.

Endocytosis

Uptake of material into the cell via vesicle formation from the membrane.

Exocytosis

Release of substances from the cell when vesicles fuse with the plasma membrane.

Aquaporin

Water-channel protein that facilitates osmosis across membranes.

Membrane potential

Electrical potential difference across a cell membrane due to ion gradients.

Excitable cells

Nerve and muscle cells capable of generating action potentials.

Na+/K+ pump

ATP-driven pump that maintains sodium and potassium gradients across the membrane.

Sodium (Na+)

Extracellular cation that participates in action potentials and osmotic balance.

Potassium (K+)

Intracellular cation essential for resting potential and repolarization.

Action potential

Rapid electrical signal that travels along excitable membranes during signaling.

Nucleus

Membrane-bound organelle containing the cell’s DNA and coordinating activities.

DNA

Deoxyribonucleic acid; genetic material of the cell.

RNA

Ribonucleic acid; participates in protein synthesis and gene expression.

mRNA

Messenger RNA; conveys genetic information from DNA to ribosomes for protein synthesis.

tRNA

Transfer RNA; delivers specific amino acids to ribosomes during translation.

rRNA

Ribosomal RNA; core component of ribosomes.

DNA polymerase

Enzyme that copies DNA during replication.

Mitosis

Division of somatic cells producing two genetically identical daughter cells.

Meiosis

Cell division that reduces chromosome number by half, producing four haploid, genetically distinct cells.

Apoptosis

Programmed or controlled cellular death to remove damaged or unnecessary cells.