DP 1 Flashcards
Active transport
The active net moment of a substance from a region of low concentration to a region of high concentration through a membrane via a carrier protein
Aquaporins
Aquaporins are integral membrane proteins from a larger family of major intrinsic proteins (MIP) that form pores in the membrane of cells
Carrier proteins
A type of protein found on the plasma membrane that is involved in facilitated diffusion and active transport
Cell membrane (plasma membrane)
The semipermeable membrane surrounding the cytoplasm of a cell
Cell surface markers
A surface protein, glycoprotein, or group of proteins that distinguish a cell or subset of cells from another defined subset of cells
Channel proteins
A type of protein found on the plasma membrane that is involved in facilitated diffusion and active transport
Endocytosis
The process in which the cell takes in a substance or particle from outside the cell by engulfing it within the plasma membrane to form a vesicle, bringing it into the cell
Endoplasmic reticulum
A network of membranous tubules within the cytoplasm of a eukaryotic cell, continuous with the nuclear membrane
Eukaryotes
An organism with cells that contain a nucleus and other membrane-bound organelles e.g. people
Exocytosis
The movement of materials out of a cell via a vesicle. The vesicle fuses with the plasma membrane, and the vesicle contents are released out of the cell
Facilitated diffusion
The passive net movement of a substance from a region of high concentration to a region of low concentration, through a membrane via a specific protein channel
Glycoprotein
Any of a class of proteins which have carbohydrate groups attached to the polypeptide chain.
Golgi complex
An organelle composed of a stack of cisternae in which proteins are assembled and then packaged in vesicles for exocytosis
Hydrophilic
Polar ions and molecules that dissolve easily in water; means ‘water loving’
Hydrophobic
Non-polar molecules that are relatively insoluble in water: means ‘ water fearing’
Hypertonic
Having a higher osmotic pressure in a fluid relative to another fluid
Hypotonic
Having a lower osmotic pressure than a particular fluid, typically a body fluid or intracellular fluid
Fluid mosaic model
Describes the structure of the plasma membrane in which phospholipids and unanchored proteins are free moving, giving the membrane fluidity. Anchored proteins are scattered throughout, giving the membrane a matrix pattern
Integral proteins
An integral membrane protein (IMP) is a type of membrane protein that is permanently attached to the biological membrane
Lysosome
An organelle vesicle containing digestive enzymes used in the digestion of waste an foreign material
Nuclear envelope
The two layered membrane that encases the nucleus of a eukaryotic cell, which separates the nucleus from other cell organelles
Osmosis
The net diffusion of free water molecules through a semi-permeable membrane from a region of high concentration to a region of low concentration
Peripheral proteins
A type of protein attached to the outer surface of the phospholipids or the integral proteins in the plasma membrane. They do not penetrate the hydrophobic centre of the plasma membrane
Phagocytosis
The engulfment of solid materials in which the plasma membrane surrounds the material, forming a vacuole (phagosome) and allowing the substance into the cell
Phospholipids
Essential component of the plasma membrane, comprised of a hydrophilic phosphate head and a hydrophobic fatty acid tail
Pinocytosis
The engulfment of a liquid substances, in which the plasma membrane surrounds the substance, forming a vesicle and allowing the substance into the cell
Prokaryotes
A type of organism with a simple cellular structure, lacking a nucleus and other membrane-bound organelles; for example, bacteria
Prokaryotic
A microscopic single-celled organism which has neither a distinct nucleus with a membrane nor other specialized organelles, including the bacteria and cyanobacteria
Protein pumps
A kind of protein that is capable of pumping out compounds that could pose a threat to the cell
Receptors
A molecule in a cell membrane that binds and responds to specific molecules such as hormones such as hormones and neurotransmitters, triggering a response
Ribosomes
A non-membrane bound organelle, made of RNA and protein, which acts as the site of translation in the process of protein synthesis
Rough endoplasmic reticulum
A large organelle comprised of layers of cistern with ribosomes studding the surface. It is the site of protein synthesis and modification
Semipermeable
Allowing certain substances to pass through it but not others, especially allowing the passage of a solvent but not of certain solutes
Simple diffusion
The passive net movement of a substance from a region of high concentration to a region of low concentration
Trans-membrane
A functional protein often composed of more than one polypeptide molecule, which spans the entire thickness foo the plasma membrane. Hydrophilic hormone receptors ion channels and ion pumps are all examples of transmembrane proteins
Vesicle
A small fluid-filled bladder, sac, cyst, or vacuole within the body
