Active Transport – Primary and Secondary Active Transport

Active Transport

Active transport is the movement of molecules across a cell membrane against their concentration gradient using energy from the cell. This energy comes from the hydrolysis of adenosine triphosphate (ATP) to adenosine diphosphate (ADP) and inorganic phosphate (P i ).

Mechanism of Cellular Active Transport

• The mechanism of cellular active transport is the process by which cells move molecules across the cell membrane against their concentration gradient. This process is powered by the cell’s energy currency, adenosine triphosphate (ATP). There are several different types of active transport, but all of them rely on the cell membrane to shuttle molecules from one side of the cell to the other.
• One type of active transport, called facilitated diffusion, relies on special proteins embedded in the cell membrane to transport molecules across the cell. These proteins act as channels or transporters that bind to the molecule and carry it across the membrane. Another type of active transport, called active transport, relies on the cell’s own energy to power the transport of molecules across the membrane. This process is powered by ATP, and it requires special proteins called transporters to ferry molecules across the membrane.
• Active transport is used to move molecules across the cell membrane against their concentration gradient. This process is powered by the cell’s energy currency, adenosine triphosphate (ATP).
• There are several different types of active transport, but all of them rely on the cell membrane to shuttle molecules from one side of the cell to the other.
• One type of active transport, called facilitated diffusion, relies on special proteins embedded in the cell membrane to transport molecules across the cell. These proteins act as channels or transporters that bind to the molecule and carry it across the membrane.

Background

The background to this question is the ongoing conflict in Syria. In 2011, a civil war began in Syria as part of the Arab Spring, a series of uprisings and protests in the Middle East and North Africa. The war has since killed over 400,000 people and displaced millions. In 2013, the Syrian government began using chemical weapons against civilians, which led to the United States and its allies launching airstrikes against the Syrian government. In 2018, the United States announced its intention to withdraw its troops from Syria, which has sparked criticism from both Democrats and Republicans.

Primary Active Transport

In primary active transport, a molecule is transported across a cell membrane against its concentration gradient. This is accomplished by using the energy of ATP to power a protein pump in the membrane. The protein pump creates a proton gradient across the membrane, with more protons on the inside of the cell. This gradient provides the energy to power the transport of molecules across the membrane.

Active Transport Model

The active transport model is a mathematical model that describes the dynamics of a population of particles subjected to active transport. The model assumes that each particle is subject to a constant force that drives it towards a target. The model can be used to predict the distribution of particles in a population over time.

Types of Primary Active Transporters

There are three types of primary active transporters: symporters, antiporters, and uniporters.

Symporters:

Symporters are proteins that use the energy in the form of a molecule of ATP to transport two molecules of a different molecule across the cell membrane. The molecules that are transported can be either molecules of the same kind (like two sugar molecules) or molecules of different kinds (like a sugar molecule and a protein molecule).

Antiporters:

Antiporters are proteins that use the energy in the form of a molecule of ATP to transport two molecules of different molecules across the cell membrane. The molecules that are transported can be either molecules of the same kind (like two sugar molecules) or molecules of different kinds (like a sugar molecule and a protein molecule).

Uniporters:

Uniporters are proteins that use the energy in the form of a molecule of ATP to transport one molecule of a different molecule across the cell membrane. The molecule that is transported can be either molecules of the same kind (like two sugar molecules) or molecules of different kinds (like a sugar molecule and a protein molecule).

Secondary Active Transport

• Secondary active transport uses the energy of a moving molecule to power the transport of another molecule across a cell membrane. This type of transport requires a protein channel in the membrane that can be opened and closed to regulate the passage of molecules. The energy for the transport process is provided by a molecule called adenosine triphosphate (ATP).
• ATP is a molecule that contains energy in the form of a high-energy phosphate bond. When this bond is broken, the energy is released and can be used to power cellular processes. In secondary active transport, the energy from ATP is used to open a protein channel in the cell membrane. This allows the passage of another molecule, which is then transported across the membrane.

Antiporter

• An antiporter is an ion transporter that exchanges ions across a cell membrane.
• The antiporter exchanges two different ions across the cell membrane.
• The antiporter is a type of ion transporter.
• Ions are molecules that have a positive or negative electrical charge.
• The antiporter exchanges two different ions across the cell membrane.
• The antiporter is a type of ion transporter that exchanges ions across a cell membrane.

Symporter

A protein that helps transport substances across membranes.

Bulk Transport

Bulk transport is the transportation of goods in large quantities, usually by truck, rail, or barge. Bulk transport is used to move commodities such as coal, grain, and iron ore.

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