What is the function of lumen in photosynthesis?

Lumen. The thylakoid lumen is a continuous aqueous phase enclosed by the thylakoid membrane. It plays an important role for photophosphorylation during photosynthesis. During the light-dependent reaction, protons are pumped across the thylakoid membrane into the lumen making it acidic down to pH 4.

What happens in the lumen?

The space inside the thylakoid discs is called the lumen, or, more specifically, the thylakoid lumen. This electrical energy is then passed from one membrane protein to another, providing the power to pump protons from the stroma into the thylakoid lumen.

Where is the lumen in the thylakoid membrane?

the thylakoid membrane, embedded in the stroma, encloses the aqueous lumen, which is the innermost compartment of the chloroplast.

What processes occur in the thylakoid lumen?

The lumen of the thylakoid contains proteins used for protein processing, photosynthesis, metabolism, redox reactions, and defense. The protein plastocyanin is an electron transport protein that transports electrons from the cytochrome proteins to Photosystem I.

What is lumen in plants?

In biology, a lumen , meaning “an opening”; plural lumina) is the inside space of a tubular structure, such as an artery or intestine. By extension, the term lumen is also used to describe the inside space of a cellular component or structure, such as the endoplasmic reticulum.

What is the lumen in a plant cell?

In cell biology, a lumen is a membrane-defined space that is found inside several organelles, cellular components, or structures: thylakoid, endoplasmic reticulum, Golgi apparatus, lysosome, mitochondrion, or microtubule.

What is the function of the lumen in the small intestine?

Large quantities of water are secreted into the lumen of the small intestine during the digestive process. Almost all of this water is also reabsorbed in the small intestine. Regardless of whether it is being secreted or absorbed, water flows across the mucosa in response to osmotic gradients.

What is lumen in biology?

In biology, a lumen (plural lumina) is the inside space of a tubular structure, such as an artery or intestine. It comes from Latin lumen ‘an opening’. It can refer to: The interior of a vessel, such as the central space in an artery, vein or capillary through which blood flows.

Why does the lumen become positively charged during the light-dependent reaction?

Why does the space inside the thylakoid become positively charged during the light-dependent reactions? ATP synthase helps H+ ions in the thylakoid space to pass through the membrane to the stroma.

Where do the H+ that accumulate in the lumen in the light come from?

H+ ions accumulate within the lumen (from splitting water & being pumped in from stroma). the membrane provides the energy to make ATP. H+ ions cannot directly cross the thylakoid membrane. The protein ATP synthase allows H+ ions to pass through it.

What is a lumen in science?

lumen, unit of luminous flux, or amount of light, defined as the amount streaming outward through one steradian (a unit of solid angle, part of the volume of space illuminated by a light source) from a uniform point source having an intensity of one candela.

What is lumen intestine?

In the intestines, the lumen is the opening inside the bowels. It is surrounded by the other parts of the intestinal wall: the mucosa, the submucosa, the muscularis, and the serosa.