48 results found

Search Results for: concentration gradient

Concentration gradient

Concentration gradient definition Concentration gradient refers to the gradual change in the concentration of solutes in a... Read More

Diffusion

Diffusion Definition Diffusion is the net passive movement of molecules or particles from regions of higher to regions of... Read More

Isotonic

Isotonic Definition What does isotonic mean? The term "isotonic" is used in physiology, anatomy, and physical chemistry.... Read More

Transport

In biology, transport refers to the act or the means by which a molecule or ion is moved across the cell membrane or via the... Read More

Active transport

Active transport is a type of cellular transport in which substances (e.g. ions, glucose, and amino acids) are transported... Read More

Simple diffusion

Simple Diffusion Definition What is simple diffusion? In biology, simple diffusion is a form of diffusion that does not... Read More

Carrier protein

Carrier protein is a type of cell membrane protein involved in facilitated diffusion and active transport of substances out... Read More

Facilitated diffusion

Facilitated diffusion is the transport of substances across a biological membrane from an area of higher concentration to an... Read More

Passive transport

Passive transport is a type of cellular transport in which substances such as ions and molecules move down their respective... Read More

Osmosis

Osmosis is the net movement of solvent molecules through a semipermeable membrane. It is similar to diffusion as the... Read More

Plant Water Regulation

A plant requires water as an essential ingredient of photolysis, the photochemical stage of photosynthesis where water is... Read More

Concentration

Definition noun (1) The measure of the amount of a sub-component (especially solute) in a solution (2) The ratio of the mass... Read More

Generation of resting membrane potential

Stephen H. Wright Department of Physiology, College of Medicine, University of Arizona, Tucson, Arizona 85724... Read More

Hyperosmotic

Hyperosmotic Definition The word Hyperosmotic is derived from two Greek words: 'hyper', meaning “excess” and 'osmos',... Read More

Water in Plants

The movement of molecules, specifically water and any solutes, is vital to understand in light of plant processes. This will... Read More

Plasma membrane

Do all cells have a plasma (or cell) membrane? Yes, all cells have a biological membrane that separates the protoplasm from... Read More

Movement of Molecules Across Cell Membranes

Diffusion Diffusion is essentially the movement of molecules from a region of higher concentration to a region of lower... Read More

Animal Water Regulation

Homeostatic control, a set environment, and how evolution and natural selection drives a species to adapt to its environment... Read More

Light-dependent reaction

Many organisms, such as green plants, convert light energy into chemical energy through the mechanism of photosynthesis. In... Read More

Chemiosmosis

Chemiosmosis Definition What is chemiosmosis? In biology, chemiosmosis refers to the process of moving ions (e.g. protons)... Read More

Hypotonic solution

Hypotonic Solution Definition What is a hypotonic solution? It refers to a solution that contains a lower amount of solute... Read More

Homeostasis

Homeostasis is the tendency not to stray from the range of favorable or ideal internal conditions. Such conditions must be... Read More

Tonicity

Definition noun (1) A property of a solution that depends on the osmotic force exerted across the membrane as influenced by... Read More

Biological Cell Introduction

It only takes one biological cell to create an organism. In fact, there are countless species of single-celled organisms,... Read More

Cell Biology

It only takes one biological cell to create an organism. In fact, there are countless species of single celled organisms,... Read More

Gradient

Definition noun, plural: gradients (1) A slope, which may be upward or downward. (2) The degree of steepness or inclination,... Read More

ATP synthase

Definition noun, plural: ATP synthases An enzyme that catalyzes the formation of ATP from the phosphorylation of ADP with... Read More

Uniport

Definition noun The transport of molecule or ion across a membrane through facilitated diffusion without coupling to the... Read More

Sarcolemma

Sarcolemma Definition What is the sarcolemma? It is the thin, transparent, extensible plasma membrane of the muscle cell.... Read More

Hypertonic

Definition adjective (1) Having a greater degree of tone, tension or tonicity (2) Having a greater osmotic pressure in a... Read More

Hydrogen

Hydrogen is one of the chemical elements found in nature. A chemical element refers to the pure substance of one type of... Read More

Hydrogen-transporting ATP synthase

Definition noun A membrane enzyme that allows the diffusion of protons (hydrogen ions) through its proton channel component... Read More

Plasmolysis

Plasmolysis is the shrinking of protoplasm away from the cell wall of a plant or bacterium. The protoplasmic shrinking is... Read More

Respiration

Organization of the Respiratory System Each lung is composed of air sacs called alveoli - the sites of gas exchange with... Read More

Amphipathic

Amphipathic is a word used to describe a chemical compound containing both polar (water-soluble) and nonpolar (not... Read More

Cotransport

Cotransport (Science: cell biology, physiology) The linked, simultaneous transport one substance across a membrane, coupled... Read More

Aldosterone

Definition noun, plural: aldosterones A mineralocorticoid with a chemical formula of C21H28O5, and controls salt and water... Read More

Circulation

Blood Blood is composed of a liquid, plasma, and blood cells such as erythrocytes (red blood cells,) leukocytes (white... Read More

Proton gradient

Proton gradient in biology, the proton gradient may be used as an intermediate energy source for heat and flagellar... Read More

Cell membrane

Definition noun plural: cell membranes ˈmembɹeɪn The cell’s outer membrane made up of a two layers of phospholipids... Read More