Cell Unit

Endomembrane system - a group of membrane and organelles in eukaryotic cells that works together to modify , package , and transport lipids and proteins.

phagocytosis - A white blood cell or phagocyte surrounds and destroys foreign substances (bacteria) and removes the dead cells.

tonoplast - membrane that surrounds the large vacuole in a mature plant cell. 

cristae - functional dynamic compartments whose shape and dimensions modulate the kinetics of chemical reactions and the structure of protein complexes. 

Mitochondrial matrix- inner space surrounded by the mitochondrial inner membrane, which contains several proteins, such as enzymes involved in the tricarboxylic acid cycle, fatty acid oxidation, amino acid degradation, and other biochemical reactions. 

Granum- a coin shaped stack of thylakoids, which are the membrane-like structures found inside the chloroplasts of plant cells. 

Stroma - The cells and tissues that support and give structure to organs, glands, or other tissues in the body. 

Peroxisome - intracellular organelle in eukaryotic cells that functions as a degradative organelle, containing oxidases that facilitate chemical oxidation reactions of various substances like toxins, amino acids, and fatty acids within its peroxisomal matrix. 

DYNEIN - family of cytoskeleton motor proteins that move along microtubules in cells. They convert chemical energy stored in ATP to mechanical work. They transport various cellular cargos, provides forces and displacements important in mitosis, and drive the beat of Eukaryotic cilia and flagella. 

Actin - a protein that is an important contributor to the contractile property of muscle and other cells

Pseudopodia - temporary arm-like projection of a eukaryotic cell membrane that is emerged in the direction of movement 

Proteoglycans - glycoproteins in which the carbohydrate units are polysaccharides that contain amino sugars. 

Integrins the principal receptors used by animal cells to bind to the extracellular matrix. 

Tight junction - membrane of neighboring cells are pressed together, preventing leakage of extracellular fluid. 

Desmosomes - anchoring junctions, fasten cells together into strong sheets. 

Gap junction - communicating junctions that provide cytoplasmic channels between adjeacent cells.

Amphipathic molecule - a compound comprising a hydrophilic head and a hydrophobic tail. 

Fluid mosaic model - describes the main characteristics of the plasma membrane. 

Integral proteins - reside within the bilayer membranes that surround cells and organelles, playing critical roles in movement of molecules across them and the transduction of energy and signals. 

Peripheral proteins - Protein that is found temporarily attached to the cell or mitochondrial membrane

Osmoregulation - the active regulation of the osmotic pressure of an organism’s body fluid, detected by osmoreceptors, to maintain the homeostasis of the organism’s water content. 

Aquaporins - proteins that facilitate the diffusion of water

Endocytosis - cellular process that allows a cell to bring substances into itself by forming a vesicle around the material and pinching it off from the cell membrane. 

Phagocytosis - cells ingesting and eliminating particles.

Pinocytosis - process by which the cell takes in the fluids along with dissolved small molecules. 

Ligands - an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex.

Receptor-mediated endocytosis - a highly efficient mechanism for cellular uptake of membrane-impermeant ligands. (Signal transduction initiation, neurotransmission, maintaining homeostasis, acquiring nutrients)

exocytosis - process for moving large molecules out of the cell to the cell exterior

Signal-transduction pathway - a series of molecular interactions triggered by the binding of a signaling molecule to its receptor, leading to the activation of various intracellular pathways involved in cell signaling.

Local regulator - chemical signals that act over short distance, reaching their target cells by diffusion. 

G-protein-linked receptor - large family of proteins that act as a cell surface receptors for a variety of signals, including hormones, neurotransmitters, and light

G-protein - guanine nucleotide-binding proteins, are a family of proteins that act as molecular switches inside cells, and are involved in transmitting signals from a variety of stimuli outside a cell to its interior. 

Tyrosine kinase - enzymes that selectively phosphorylation tyrosine residue in different substrates. Receptor tyrosine kinases are activated by ligand binding to their extracellular domain. 

Tyrosine-kinase receptor - subclass of tyrosine kinases that are involved in mediating cell to cell communication and controlling a wide range of complex biological functions, including cell growth, motility, differentiation, and metabolism

Protein kinase -enzymes that regulate the biological activity of proteins by phosphorylation of specific amino acids with ATP as the source of phosphate, thereby inducing a conformational change from an inactive to an active form of the protein. 

Protein phosphatases - enzymes that remove phosphate groups from proteins, and are essential for regulating cell signaling and cell regulation. 

Second messenger - small molecule or ion that transmits signals from cell-surface receptors to effector proteins. 

Cyclic AMP - cyclic adenosine monphosphate is a cellular signal that occurs within cells that is important for many biological processes (cell growth, metabolism, olfaction)

Adenylyl cyclase - an enzyme that catalyzes the conversion of ATP into cyclic adenosine monophosphate.

DAG - diacylglycerol, an important lipid both is an intermediate in lipid biosynthetic pathways and can act as a signaling lipid

Inositol trisphosphate - a molecule that controls many cellular processes by releasing calcium from intracellular stores. (Second messenger)

Scaffolding proteins - proteins that bind to multiple other proteins to organize them into functional units.