74 results found

Search Results for: gradient

Concentration gradient

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

Active transport

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

Generation of resting membrane potential

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

Chemiosmosis

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

Diffusion

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

Passive transport

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

Hypotonic solution

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

Isotonic

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

Facilitated diffusion

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

Cellular respiration

Cellular Respiration Definition The main function of cellular respiration is to break down glucose to form energy. What is... Read More

Osmosis

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

Mitochondrion

Mitochondrion Definition What are mitochondria? The term “mitochondrion” comes from the two words of the Greek... Read More

Hyperosmotic

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

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

Plant Water Regulation

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

Chemiosmotic coupling

Definition noun The process that couples or links the electron transport chain to ATP synthesis. Supplement Chemiosmosis is... 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

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

Chemiosmotic coupling hypothesis

Definition noun A theory postulated by the biochemist Peter Mitchell in 1961 to describe ATP synthesis by way of a proton... Read More

Chemotaxis

Definition noun The directional movement of an organism or a living motile cell in response to certain diffusible chemicals... Read More

Chemokinesis

Definition noun A behavioral response of a cell or an organism to a soluble chemical that leads to random or directionally... 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

Electron transport chain

Definition noun A group of compounds that pass electron from one to another via redox reactions coupled with the transfer... Read More

Chemotactic

Chemotactic --> chemotaxis a response of motile cells or organisms in which the direction of movement is affected by the... Read More

Grade

Grade a harsh scraping or cutting; a grating. The grade of hatchets fiercely thrown. On wigwam log, and tree, and stone.... Read More

Cell membrane

Cell Membrane Definition Just like any non-living body possesses a plastic or paper packaging material that keeps the... Read More

Smooth muscle

The smooth muscle can be described as a type of muscle in the human body that is non-striated and involuntary in action.... Read More

Carbon fixation

Carbon Fixation Definition We know that the earth contains many elements. The periodic table shows us just how many... 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

Chemiosmotic hypothesis

Definition noun A theory postulated by the biochemist Peter Mitchell in 1961 to describe ATP synthesis by way of a proton... Read More

Uniport

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