Water Concentration Definition

Water Potential - Definition, Formula & Quiz | Biology ...

Apr 28, 2017· Water potential is what allows water to get into plant roots when there is more solute within the root cells than the water in the soil. And as we go up the plant, Ψ decreases more and more, drawing water into the stems and then the leaves, which constantly get water evaporated out of them, maintaining a high solute concentration and a low Ψ.

Melatonin - Wikipedia

Melatonin is a hormone primarily released by the pineal gland at night, and has long been associated with control of the sleep–wake cycle. As a dietary supplement, it is often used for the short-term treatment of insomnia, such as from jet lag or shift work, and is typically taken orally. Evidence of its benefit for this use, however, is not strong. A 2017 review found that sleep onset ...

Pyrogen | definition of pyrogen by Medical dictionary

pyrogen [pi´ro-jen] an agent that causes fever; called also pyretic and pyrectic. adj., adj pyrogen´ic. endogenous pyrogen a low-molecular-weight protein that is produced by phagocytic leukocytes in response to stimulation by exogenous pyrogens and released into the circulation; it induces fever by acting on the preoptic area of the hypothalamus to ...

Concentration Quantities and Unit Conversions - EWT Water ...

May 05, 2018· The ↓pH value is not a concentration quantity by definition, however can be considered as such for most water chemistry applications. Neither is the ↓ electrical conductivity a concentration quantity, but instead an approximate indicator for the concentration of total dissolved solids (TDS) in water.

Magic – d20PFSRD

Concentration Checks and Casting Spells. To cast a spell, you must concentrate. If something interrupts your concentration while you''re casting, you must make a concentration check or lose the spell. When you make a concentration check, you roll d20 and add your caster level and the ability score modifier used to determine bonus spells of the same type.

Base Definition in Chemistry - ThoughtCo

May 06, 2019· A strong base completely dissociates into its ions in water or is a compound that can remove a proton (H +) from a very weak acid.Examples of strong bases include sodium hydroxide (NaOH) and potassium hydroxide (KOH). A weak base incompletely dissociates in water. Its aqueous solution includes both the weak base and its conjugate acid.

Osmotic concentration - Wikipedia

Osmotic concentration, formerly known as osmolarity, is the measure of solute concentration, defined as the number of osmoles (Osm) of solute per litre (L) of solution (osmol/L or Osm/L). The osmolarity of a solution is usually expressed as Osm/L (pronounced "osmolar"), in the same way that the molarity of a solution is expressed as "M" (pronounced "molar").

What is Copper Corrosion? - Definition from Corrosionpedia

Mar 19, 2015· Copper is considered to be a noble metal, and as a result is able to resist attack by oxygen.The metal is basically immune to corrosion due to a naturally occurring protective film known as a patina that forms on the metal''s surface. If this protective film, usually consisting of reddish-brown cuprous oxide (Cu 2 O), is destroyed, then copper will eventually corrode.

Chronic toxicity - Wikipedia

Chronic toxicity, the development of adverse effects as a result of long term exposure to a contaminant or other stressor, is an important aspect of aquatic toxicology. Adverse effects associated with chronic toxicity can be directly lethal but are more commonly sublethal, including changes in growth, reproduction, or behavior.

Molar Definition in Chemistry (Unit)

Nov 07, 2019· Molar refers to the unit of concentration molarity, which is equal to the number of moles per liter of a solution chemistry, the term most often refers to molar concentration of a solute in a solution. Molar concentration has the units mol/L or M.

Cytosol - Wikipedia

In contrast to extracellular fluid, cytosol has a high concentration of potassium ions and a low concentration of sodium ions. This difference in ion concentrations is critical for osmoregulation, since if the ion levels were the same inside a cell as outside, water would enter constantly by osmosis - since the levels of macromolecules inside cells are higher than their levels outside.

Semipermeable Membrane: Definition & Examples | Biology ...

Feb 13, 2017· The concentration of the solution bound by a semipermeable membrane can be described by its tonicity as compared to the environment or other cells. Because biological membranes are permeable to water but not solutes, water tends to move into cells that are hypertonic to their environment, while water moves out of cells that are hypotonic .

Definitions of Acids and Bases, and the Role of Water

The concentration of water is therefore 55.35 molar. The concentration of the H + and OH-ions formed by the dissociation of neutral H 2 O molecules at this temperature is only 1.0 x 10-7 mol/L. The ratio of the concentration of the H + (or OH-) ion to the concentration of the neutral H 2 O molecules is therefore 1.8 x 10-9.