The directed movement of urea into, out of or within the cell. Urea is the water-soluble compound H2N-CO-NH2.

The directed movement of spermidine, N-(3-aminopropyl)-1,4-diaminobutane, a polyamine formed by the transfer of a propylamine group from decarboxylated S-adenosylmethionine to putrescine, into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore.

The directed movement of putrescine into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore. Putrescine is 1,4-diaminobutane, the polyamine formed by decarboxylation of ornithine and the metabolic precursor of spermidine and spermine.

The directed movement of putrescine into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore. Putrescine is 1,4-diaminobutane, the polyamine formed by decarboxylation of ornithine and the metabolic precursor of spermidine and spermine.

The directed movement of spermidine, N-(3-aminopropyl)-1,4-diaminobutane, a polyamine formed by the transfer of a propylamine group from decarboxylated S-adenosylmethionine to putrescine, into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore.

The chemical reactions and pathways resulting in the breakdown of urea, the water soluble compound O=C-(NH2)2.

The process in which urea, the water-soluble compound H2N-CO-NH2, is transported from one side of a membrane to the other by means of some agent such as a transporter or pore.

Any process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of deprivation of nitrogen.

The process in which urea, the water-soluble compound H2N-CO-NH2, is transported from one side of a membrane to the other by means of some agent such as a transporter or pore.

The process in which urea, the water-soluble compound H2N-CO-NH2, is transported from one side of a membrane to the other by means of some agent such as a transporter or pore.

The directed movement of urea into, out of or within the cell. Urea is the water-soluble compound H2N-CO-NH2.

The membrane surrounding a cell that separates the cell from its external environment. It consists of a phospholipid bilayer and associated proteins.

The irregular network of unit membranes, visible only by electron microscopy, that occurs in the cytoplasm of many eukaryotic cells. The membranes form a complex meshwork of tubular channels, which are often expanded into slitlike cavities called cisternae. The ER takes two forms, rough (or granular), with ribosomes adhering to the outer surface, and smooth (with no ribosomes attached).

The membrane surrounding a cell that separates the cell from its external environment. It consists of a phospholipid bilayer and associated proteins.

The part of a cell encompassing the cell cortex, the plasma membrane, and any external encapsulating structures.

The membrane surrounding a cell that separates the cell from its external environment. It consists of a phospholipid bilayer and associated proteins.

All of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures.

A compound membranous cytoplasmic organelle of eukaryotic cells, consisting of flattened, ribosome-free vesicles arranged in a more or less regular stack. The Golgi apparatus differs from the endoplasmic reticulum in often having slightly thicker membranes, appearing in sections as a characteristic shallow semicircle so that the convex side (cis or entry face) abuts the endoplasmic reticulum, secretory vesicles emerging from the concave side (trans or exit face). In vertebrate cells there is usually one such organelle, while in invertebrates and plants, where they are known usually as dictyosomes, there may be several scattered in the cytoplasm. The Golgi apparatus processes proteins produced on the ribosomes of the rough endoplasmic reticulum; such processing includes modification of the core oligosaccharides of glycoproteins, and the sorting and packaging of proteins for transport to a variety of cellular locations. Three different regions of the Golgi are now recognized both in terms of structure and function: cis, in the vicinity of the cis face, trans, in the vicinity of the trans face, and medial, lying between the cis and trans regions.