fluid

Vacuole

...rials that might be toxic to the cell, maintaining fluid balance (called turgor ) within the cell, exporting unwanted substances from the cell, or even determining relative cell size. The cavity that is the vacuole is considered nonprotoplasmic and the contents classified as ergastic according to some a...

Stroma

...a biological cell , tissue , or organ . 2) The fluid filled area of a chloroplast outside of the thylakoid membranes wherein the light-independent reactions ( Calvin Cycle and Carbon fixation ) of photosynthesis take place....

Spermatogenesis

...e lumen of the seminiferous tubule and travel with fluid from the testis into the epididymis for further maturation processes allowing them to swim forward and fertilize an ovum....

Sperm

... cell that is the male gamete . It is carried in fluid called semen , and is capable of fertilising an egg cell to form a zygote . A zygote can grow into a new organism, such as a human. Sperm cells contain half of the genetic information needed to create life. Generally, the sex of the offspri...

Skeleton

... exoskeleton ), internal (an endoskeleton ), and fluid based (a hydrostatic skeleton ), though hydrostatic skeletal systems may be classified separately from the other two since they lack hardened support structures. Large external skeletal systems support proportionally less weight than endoskeletons...

Semen

Semen or ejaculate is the fluid discharged from the penis during ejaculation ,...lk of the semen is composed of seminal plasma, the fluid portion of semen.This fluid is contributed by the accessory male reproductive organs . Some 60% of ...

Ribosome

... can float freely in the cytoplasm (the internal fluid of the cell) or bind to another organelle called the endoplasmic reticulum . Since ribosomes are ribozymes , it is thought that they might be remnants of the RNA world . Overview Ribosomes consist of two subunits (Figure 1) that fit together (...

Cell membrane

... described as a 'fluid mosaic' - a two-dimensional fluid of freely diffusing lipids, dotted or embedded wit...ally, rather than presenting always a formless and fluid contour, the plasma membrane surface of cells may show structure. Returning to the example of epithe...

Phospholipid

...e is partially permeable , very flexible, and has fluid properties, in which embedded proteins and phospholipid molecules are constantly moving laterally across the membrane because of the forces generated by their vibrations. Such movement can be described by the Fluid Mosaic Model , which basically des...

Peroxisome

...at separates them from the cytosol (the internal fluid of the cell). Peroxisomes were discovered by Christian de Duve in 1965 . Unlike lysosomes , which are formed in the Golgi apparatus , peroxisomes usually self-replicate by enlarging and then dividing, although there is some indication new ones m...

Osmoregulation

...y waste, such as ammonia , from the intracellular fluid by both diffusion and active transport. As osmoti...vertebrates Four processes occur: filtration - fluid portion of blood (plasma) is filtered from nephron (functional unit of vertebrate kidney) structure ...

Nutrition

...uidance may not be the best advice to follow: more fluid and responsive channels for advice may be needed in the future. "Recommended daily allowances" and the "five portions" policies are increasingly looking like arbitrary figures, as our knowledge increases. Cornell nutritional biochemist T. Colin Camp...

Monoclonal antibody

...), they produce tumors containing an antibody-rich fluid called ascites fluid. In the above process, myeloma cell lines are used that have lost their ability to produce their own antibodies, so as to not dilute the target antibody. Furthermore, one uses only myeloma cells that have lost a specific enz...

Lung

... the pleural cavity that is filled with pleural fluid ; this allows the inner and outer layers to slide over each other, and prevents them from being separated easily. The left lung is smaller than the right one to give way for the heart. Human lungs See human lung . Avian lungs Birds have a ...

Kidney

...ltering the blood, then reabsorbing some necessary fluid and molecules while secreting other, unneeded mole...e cells are called podocytes ) Due to pressure, fluid in the blood is forced out of the glomerulus, through these three layers and into the Bowman's space...

Joint

...thin the articular capsule. It secretes synovial fluid into the joint, which nourishes and lubricates the articular cartilage. The synovium is separated from the capsule by a layer of celluar tissue that contains blood vessels and nerves. Synovial joints can be further grouped by their shape, which co...

Insulin

...uivalent amount of fat, protein, carbohydrate, and fluid in some other form. Their particular reaction to skimmed milk is different than other diabetics', but the same amount of whole milk is likely to cause a still different reaction even in that same person. Whole milk contains considerable fat while ski...

Immune system

...ystem also function in the return of extracellular fluid to the blood. Bacteria and monocellular organisms have an "immune system" (under the broader of the two definitions above) designed to combat bacteriophages (viruses that infect bacteria). They do this by simultaneously expressing restriction en...

Homeostasis

.... The body fluids include blood plasma , tissue fluid and intracellular fluid . The maintenance of a steady state in these fluids is essential to living things as the lack of it...

Genetic fingerprinting

...mple of blood, saliva, semen, or other appropriate fluid or tissue. A common method is a buccal swab . Next, restriction fragment length polymorphism (RFLP) analysis is performed by using a restriction enzyme to cut the DNA into fragments which are separated into bands during agarose gel electroph...

Free energy

...stance, in chemistry one is usually concerned with fluid systems at constant temperature, undergoing chemical reaction in closed containers (at constant volume) or in open containers (at constant pressure). In the first case one would use the Helmholtz free energy as a measure of available work, and in...

Foot and mouth disease

...h a fine porcelain-glass filter and found that the fluid that was collected could still cause the disease in healthy animals. FMD occurs throughout much of the world, including parts of Europe , Africa , Asia , and South America . While currently (July 2001) some countries, including Canada , the ...

Cell membrane

... described as a 'fluid mosaic' - a two-dimensional fluid of freely diffusing lipids, dotted or embedded wit...ally, rather than presenting always a formless and fluid contour, the plasma membrane surface of cells may show structure. Returning to the example of epithe...

Fick's law of diffusion

...lux limiter . The exchange rate of a gas across a fluid membrane can be determined by using this law together with Graham's law . See also Gas exchange Lung Alveoli References W.F. Smith, Foundations of Materials Science and Engieering 3 rd ed. , McGraw-Hill (2004)...

Electrophysiology

...blish an electrochemical junction with the pipet fluid and the tissue or cell into which the pipet is inserted (typically with the aid of a microscope and finely adjustable pipet holders, known as micromanipulators). The chloride-coated silver wire connects back to the amplifier. Classically, electrophys...

Diffusion

... these cases, diffusion is the result of turbulent fluid motion rather than chemical reactions or the a...of transport is governed by the viscosity of the fluid and the momentum gradient. Osmosis Osmosis is the diffusion of a solute across a selectiv...

Dialysis

...abdominal body cavity around the intestine . The fluid is left there for a while to absorb waste products...area to work, a way to elevate the bag of dialysis fluid and a method of warming the fluid are all that is needed. The main consideration is the very high po...

Digestion

... acid and other digestive enzymes with digestive fluid to further decompose it chemically. As the acidic level changes in the stomach and later parts of the digestive tract, more enzymes are activated or deactivated to extract and process various nutrients. After being processed in the stomach, food...

Diabetes mellitus

...ipsia (increased thirst, and consequent increased fluid intake). There may also be weight loss (despite no...is requires water to carry it and causes increased fluid loss, which must be replaced. The lost blood volume will be replaced from water held inside body cel...

Cytosol

...ch also includes the organelles ) is the internal fluid of the cell , and a large part of cell metabolis.... neutral), whereas the pH of the extracellular fluid is 7.4....

Chloroplast

...ming chloroplasts with four membrane layers. The fluid within the chloroplast is called the stroma , corresponding to the cytoplasm of the bacterium, and contains tiny circular DNA and ribosomes , though most of their proteins are synthesized by the cell nucleus. Within the stroma are stacks of t...

Brain

... body functions such as heartbeat, blood pressure, fluid balance and body temperature. Functions of the bra...a mater . The brain is suspended in cerebrospinal fluid , which circulates between layers of the meninges and through cavities in the brain called ventricl...

Blood

... Blood is a circulating tissue composed of fluid plasma and cells ( red blood cells , white bl...lood. The other 55% is blood plasma , a yellowish fluid that is the blood's liquid medium. The normal pH of human arterial blood is approximately 7.40. T...

Biomechanics

... and mechanical engineering disciplines such as fluid mechanics and solid mechanics , play prominent roles in the study of biomechanics. By applying the laws and concepts of physics, biomechanical mechanisms and structures can be simulated and studied. Relevant mathematical tools include linear alge...

Biology

...eality the boundaries between disciplines are very fluid and most disciplines borrow techniques from each other frequently. For example evolutionary biology leans heavily on techniques from molecular biology to determine DNA sequences which assist in understanding the genetic variation of a population; ...

Albumin

...his, and thus need less albumin to maintain proper fluid distribution. Functions of albumin: Maintains oncotic pressure Transports thyroid hormones Transports other hormones, particularly fat soluble ones Transports fatty acids ("free" fatty acids) Transports unconjugated bilirubin Transp...