Cells Flashcards
(23 cards)
Exocytosis
Exocytosis is a process in which an intracellular vesicle (membrane bounded sphere) moves to the plasma membrane and subsequent fusion of the vesicular membrane and plasma membrane ensues. Many cellular processes involve exocytosis.
Phagocytosis
In cell biology, phagocytosis (from Ancient Greek meaning “to devour”, (kytos) , meaning “cell”, and -osis, meaning “process”) is the process by which a cell—often a phagocyte or a protist—engulfs a solid particle to form an internal vesicle known as a phagosome.
Contractile vacuole
A contractile vacuole (abbreviation: CV) is a sub-cellular structure (organelle) involved in osmoregulation. It is found predominantly in protists and in unicellular algae. It was previously known as pulsatile or pulsating vacuole.
Osmosis
A contractile vacuole (abbreviation: CV) is a sub-cellular structure (organelle) involved in osmoregulation. It is found predominantly in protists and in unicellular algae. It was previously known as pulsatile or pulsating vacuole.
Facilitated diffusion
Facilitated diffusion (also known as facilitated transport or passive-mediated transport) is the process of spontaneous passive transport (as opposed to active transport) of molecules or ions across a biological membrane via specific transmembrane integral proteins.
Plasmolysis
Plasmolysis is the process in which cells lose water in a hypertonic solution. The reverse process, cytolysis, can occur if the cell is in a hypotonic solution resulting in a lower external osmotic pressure and a net flow of water into the cell.
Endocytosis
Endocytosis is a form of active transport in which a cell transports molecules (such as proteins) into the cell (endo- + cytosis) by engulfing them in an energy-using process.
Vesicle
In cell biology, a vesicle is a small structure within a cell, consisting of fluid enclosed by a [lipid bilayer]. Vesicles can form naturally, for example, during the processes of secretion (exocytosis), uptake (phagocytosis and endocytosis) and transport of materials within the cytoplasm.
Concentration gradient
The formal definition of concentration gradient is the process of particles, which are sometimes called solutes, moving through a solution or gas from an area of higher number of particles to an area of lower number of particles. The areas are typically separated by a membrane.
Equilibrium
The state in which the concentrations of the diffusing substance in the two compartments are the same or become equal.
Turgor pressure
Turgor pressure pushes the plasma membrane against the cell wall of plant, bacteria, and fungi cells as well as those protist cells which have cell walls.
Phagocyte
a type of cell within the body capable of engulfing and absorbing bacteria and other small cells and particles.
Ion channel
Ion channels are pore-forming membrane proteins whose functions include establishing a resting membrane potential, shaping action potentials and other electrical signals by gating the flow of ions across the cell membrane, controlling the flow of ions across secretory and epithelial cells, and regulating cell volume.
Cyltolysis
Cytolysis, or osmotic lysis, occurs when a cell bursts due to an osmotic imbalance that has caused excess water to move into the cell.
Isotonic
The term isotonic may refer to; Isotonic (exercise physiology), a type of muscle contraction. Isotonic regression, a type of numerical analysis. Isotonic, one of three types of tonicity that characterize a solution’s concentration. A sports drink that contains similar concentrations of salt and sugar to the human body.
Hypotonic
In a hypotonic solution the total molar concentration of all dissolved solute particles is less than that of another solution or less than that of a cell. If concentrations of dissolved solutes are less outside the cell than inside, the concentration of water outside is correspondingly greater.
Hypertonic
There are three types of solutions that can occur in your body based on solute concentration: isotonic, hypotonic, and hypertonic. An isotonic solution is one in which the concentration of solutes is the same both inside and outside of the cell.
Diffusion
Diffusion refers to the process by which molecules intermingle as a result of their kinetic energy of random motion. Consider two containers of gas A and B separated by a partition. The molecules of both gases are in constant motion and make numerous collisions with the partition.
Passive transport
Passive transport is a movement of biochemicals and other atomic or molecular substances across cell membranes without need of energy input.
Active transport
Active transport is the movement of molecules across a cell membrane from a region of their lower concentration to a region of their higher concentration in the direction against some gradient or other obstructing factor (often a concentration gradient).
Sodium/Potassium pump
sodium-potassium pump. Type: Term. Definitions: 1. a membrane-bound transporter found in nearly all mammalian cells that transports potassium ions into the cytoplasm from the extracellular fluid while simultaneously transporting sodium ions out of the cytoplasm to the extracellular fluid.
Pinocytosis
In cellular biology, pinocytosis (pino- + cytosis), otherwise known as cell drinking, fluid endocytosis, and bulk-phase pinocytosis, is a mode of endocytosis in which small particles are brought into the cell, forming an invagination, and then suspended within small vesicles.
Carrier protein
Channel proteins facilitate the diffusion of different molecules, while carrier proteins are involved in the movement of ions, small molecules, or macromolecules, such as another protein, across a biological membrane.
