Biological membrane
A biological
membrane or biomembrane is a
membrane which acts as a barrier within or around a cell . It is a lipid bilayer , being composed of a double layer of lipid -class molecules , specifically phospholipids , with occasional proteins intertwined, some of which function as chan...
Chloroplast membrane
Chloroplasts contain several important membranes , vital for their function. Like mitochondria , chlorplasts have a double-membrane envelope, called the chloroplast envelope . Each
membrane is a phospholipid bilayer , between 6 and 8 nm thick, and the two are separated by a gap of 10-20...
Cell membrane
A component of every biological cell , the selectively permeable cell
membrane (or plasma
membrane or plasmalemma ) is a thin and structured bilayer of phospholipid and protein molecules that envelopes the cell . It separates a cell's interior from its surroundings and controls what...
Cell membrane
A component of every biological cell , the selectively permeable cell
membrane (or plasma
membrane or plasmalemma ) is a thin and structured bilayer of phospholipid and protein molecules that envelopes the cell . It separates a cell's interior from its surroundings and controls what...
Actin
...st case, one end of myosin is bound to the plasma
membrane while the other end walks towards the plus end of the actin filament. This pulls the
membrane into a different shape relative to the cell cortex..., form the cells cortex. This underlies the plasma
membrane and is responsible for the shape of the cell.
...
Acrosome
...ucida, this reaction takes place, during which actin polymerizes to form the acrosomal process ; also, the acrosomal vesicle fuses with the plasma
membrane of the egg cell, and digestive enzymes are released from the sperm to digest the zona pellucida and give access to the egg.
See also
Capaci...
Acrosome
...ucida, this reaction takes place, during which actin polymerizes to form the acrosomal process ; also, the acrosomal vesicle fuses with the plasma
membrane of the egg cell, and digestive enzymes are released from the sperm to digest the zona pellucida and give access to the egg.
See also
Capaci...
Active transport
... movement of desired substance across a membrane, independent of any other species. Secondary transport concerns the diffusion of one species across a
membrane to drive the transport of another.
Primary
Primary active transport directly uses energy to transport molecules across a membrane. Most of th...
Albumin
...d
for proper distribution of body fluids between intravascular compartments
and body tissues. Albumin is negatively charged. The glomerular basement
membrane is also negatively charged, this prevents the filtration of albumin in the urine. In nephrotic syndrome, this property is lost, and there is more albu...
Anatomy
...s (not classified):
Artery
Coelom
Diaphragm
Gastrointestinal tract
Hair
Exoskeleton
Lip
Nerve
Peritoneum
Serous
membrane
Skeleton
Skull
Spinal cord
Vein
See also
List of anatomical topics
List of human anatomical features
Important p...
Antibiotic
...etronidazole, quinolones, novobiocin
Drugs which interfere with RNA synthesis
Rifampin (rifampicin)
Drugs which interfere with cell
membrane function
Polymyxin B, gramicidin
Antibiotics can also be classified by the organisms against which they are effective, and by the type of ...
Antibody
...0 kD. It can be found on the surface of the plasma
membrane of basophils and mast cells of connective tis... This complex is moved to the outside of the cell
membrane , where it can be recognized by a T lymphocyte , ...hich compares it to similar structures on the cell
membrane of a B lymphocyte . If it finds a matching pair, ...
Apoptosis
... the nuclear envelope . At this stage, the double
membrane that surrounds the nucleus still appears complete;... due to the degradation of DNA [4] .
Plasma
membrane blebbings.
The cell is phagocytosed , or ,
...he major extrinsic mediator of apoptosis. The cell
membrane has two specialized receptors for TNF: TNF-R1 and ...
Archaea
...also set the Archaea apart. Unlike most bacteria, they have a single cell
membrane that lacks a peptidoglycan wall. Further, both bacteria and eukaryotes ...lace eukaryotes closer to Eurarchaeota than Crenarchaeota are, although the
membrane chemistry suggests otherwise. However, the discovery of archaean-like gene...
ATP synthase
...is fashion is termed oxidative phosphorylation .
Same process takes place in mitochondria , were ATP synthase is located in the inner mitochondrial
membrane (so that F 1 -part sticks into mitochondrial matrix, were ATP synthesis takes place).
Plant ATP synthase
In plants ATP synthase is also present...
ATPase
...widely used in all known forms of life .
Some such enzymes are integral
membrane proteins (anchored within biological membranes ), and move solutes acro...ically preferred direction of movement—that is, from the side of the
membrane where they are in low concentration to the side where they are in high conc...
B cell
...e produced in all other vertebrates.
The human body makes hundreds of different types of B cells, and each type has a unique receptor protein on its
membrane that will bind to one particular antigen; at any one time in the human body millions of B cells are circulating in the blood and lymph, but are not ...
Bacterium
...
Gracilicutes - bacteria with a second cell
membrane containing lipids , giving them Gram-negative stains
Firmicutes - bacteria with a single
membrane and thick peptidoglycan wall, giving them Gram-... stains
Mollicutes - bacteria with no second
membrane or wall, giving them Gram-negative stains
Th...
Biochemistry
...of cell metabolism has been extensively described. Other areas of biochemistry include the genetic code ( DNA , RNA ), protein synthesis , cell
membrane transport, and signal transduction .
Contents showTocToggle("show","hide")
1 Development of biochemistry
2 Subdisciplines
...
Biophysics
...tical analysis .
Medicine and neuroscience - tackling neural networks experimentally (brain slicing) as well as theoretically (computer models),
membrane permitivity, gene therapy, understanding tumors.
Pharmacology and physiology - channel biology, biomolecular interactions, cellular membranes, p...
Brain
... are caused by germs. Viral or bacterial infection of the meninges, the
membrane that covers the brain, can lead to meningitis . Bovine spongiform encepha...he development of research in bioelectricity and to the discovery of the
membrane potential , action potential , etc., by researchers such as Emil du Bois-...
Cell biology
...s, such as those to be incorporated in membranes (
membrane proteins ), are transported into the ER during s...ocessed in the Golgi apparatus . From the Golgi,
membrane proteins can move to the plasma
membrane , to other subcellular comparments or they can be ...
Cell nucleus
...0 to 20 micrometres .
It is enclosed by a double
membrane called the nuclear envelope . The inner and outer
membrane fuse at regular intervals, forming nuclear pores ... reactions happening within the nucleus. The outer
membrane is continuous with the rough endoplasmic reticulu...
Cell growth
...rily for nutrient storage can have a smooth surface membrane, but metabolically active large cells often have some sort of folding of the cell surface
membrane in order to increase the surface area available for transport functions.
Yeast cell size regulation
The relationship between cell size and c...
Cellular respiration
...lized due to such losses as the cost of moving pyruvate into mitochondria. This takes place in the mitochondria in eukaryotic cells , and at the cell
membrane in prokaryotic cells .
Anaerobic respiration (Fermentation)
" Anaerobic respiration" It does not require oxygen. True anaerobic respiration ...
Cell metabolism
...
Protein catabolism is the breakdown of proteins into amino acids and simple derivative compounds, for transport into the cell through the plasma
membrane and ultimately for the polymerisation into new proteins via the use of ribonucleic acids ( RNA ) and ribosomes .
See also
Biochemistry
...
Chemiosmotic hypothesis
...unctioned as a kind of electrochemical capacitor , using the energy of NADH and FADH 2 to create a proton gradient across the mitochondrial
membrane and that this energy was used by a reversible proton pump , the ATP synthase , to create ATP . This was a radical proposal at the time, and not we...
Chloroplast
...plants. Both organelles are surrounded by a double
membrane with an intermembrane space; both have their own D...ining chloroplasts, forming chloroplasts with four
membrane layers.
The fluid within the chloroplast is cal... thylakoid.
The photosynthetic proteins in the
membrane bind chlorophyll , which is present with various ...
Cilium
...d scientists to re-evaluate its physiological role(s) in the cell signaling and the control of cell growth and development.
A cilium has an outer
membrane that surrounds a core called an axoneme , which contains nine pairs of microtubule doublets and other associated proteins. Motile cilia have a c...
Cisterna
...terna, Italy .
A cisterna (plural cisternae ) comprises a flattened
membrane disk which makes up the Golgi apparatus . A typical Golgi has anywhere fro...also carry structural proteins important for its maintenance as a flattened
membrane and its stacking upon each other.
The earliest cisternae are called the...
Ion gradient
...is fashion is termed oxidative phosphorylation .
Same process takes place in mitochondria , were ATP synthase is located in the inner mitochondrial
membrane (so that F 1 -part sticks into mitochondrial matrix, were ATP synthesis takes place).
See also
Transmembrane potential difference
...
Crista
... Cristae are the infoldings of the inner
membrane of a mitochondrion . They are studded with proteins, including ATP synthase and a variety of cytochromes , and function in cellular respiration ...
Cytoplasm
...is the colloidal , semi-fluid matter contained within the cell 's plasma
membrane , in which organelles are suspended. In contrast to the protoplasm , the...mes , ribosomes ), several vacuoles , cytoskeletons as well as complex
membrane structures (e.g. endoplasmic reticulums or the golgi apparatus ).
...
Cytoskeleton
...enance of cell shape. All non-spherical bacteria have genes encoding actin-like proteins, and these proteins form a helical network beneath the cell
membrane that guides the proteins involved in cell wall biosynthesis .
Some plasmids encode a partitioning system that involves an actin-like protein ParM...
Cytotoxic T cell
...d tumor cells.
Once activated by a MHC-antigen complex, T C cells release the protein perforin , which forms pores in the target cell's plasma
membrane ; this causes ions and water to flow into the target cell, making it expand and eventually lyse . T C also release granzyme , a serine protease ,...
Cytosol
...rd the outside of the cell. Water flows into the cell, making the cell larger. To prevent the cell from bursting apart, molecular pumps in the plasma
membrane , the cytoskeleton, the tonoplast or the cell wall (if present), are used to counteract the osmotic pressure.
Details
The cytosol is 20% to 3...
Developmental biology
...ula , blastulation , chorion , chrysalis , cleavage , ectoderm , embryo , embryogenesis , embryogeny , embryology , endoderm , extra-embryonic
membrane , fetus (or foetus ), gastrula , gastrulation , germ layer , germ plasm , germination , induction , juvenile , larva , maternal effect , m...
Depolarization
... refers to the event a cell undergoes when its
membrane potential grows more positive with respect to the... Compare to hyperpolarization . Depolarization of
membrane potentials is important for other cell types, part...icularly muscle cells.
Related topics
membrane potential
action potential
...
Dialysis
...erent. It works by having the blood flow along one side of a semipermeable
membrane , with the dialysis solution flowing along the other side. Due to the difference in osmolarity between the two liquids, water traverses the
membrane in order to dilute the dialysis liquid, carrying along the unwanted blood c...
Diffusion
...ons depends on the concentration gradient, and the
membrane potential. The net flux of ions can be altered by ...sion of a solute across a selectively permeable
membrane .
Photon diffusion
When photons travel ...r junction transistor
Brownian motion
Cell
membrane
Circulatory system
Diffusion equation ...