Pronunciation: [sˈɪv sˈɛl] (IPA) 
The word "sieve cell" is spelled using the International Phonetic Alphabet (IPA) as ['sɪv sɛl]. In this transcription, the "s" sounds are pronounced as "siv" and the "e" in "sieve" is pronounced with a short "ɛ" sound. The "c" in "cell" is pronounced as a "s" sound, and the stress is on the first syllable, "siv." A sieve cell is a type of cell found in plants that has small pores allowing for the flow of water and nutrients.
A sieve cell is a specialized type of plant cell that is primarily involved in the transportation of nutrients throughout the plant's vascular system. As part of the phloem tissue, sieve cells play a crucial role in facilitating the movement of organic compounds, such as sugars and amino acids, from the site of production (source) to the sites of utilization or storage (sinks) within the plant.
Sieve cells are elongated, slender cells that are found in vascular plants, particularly in gymnosperms, which include conifers. They are characterized by the presence of sieve areas or sieve plates, which are specialized regions of the cell walls containing numerous pores. These sieve areas allow for the passage of the phloem sap, a fluid rich in organic molecules, from one cell to another.
The movement of nutrients in sieve cells is facilitated by the pressure gradient created through active transport, as well as the assistance of companion cells, which are closely associated with sieve cells and provide metabolic support. Additionally, sieve cells lack nuclei, ribosomes, and other organelles, allowing for an unimpeded flow of phloem sap through the interconnected pores.
It is worth noting that sieve cells differ from sieve tubes found in angiosperms, as the latter are composed of multiple cells called sieve-tube members. Sieve cells are structurally simpler and typically have a lower capacity for long-distance transport. Nonetheless, both sieve cells and sieve tubes serve as essential conduits for the distribution of organic compounds within plants.
The word "sieve" comes from the Old English word "sife" which means a sieve or a strainer. This word is derived from the Proto-Germanic word "*sibjō" which also means sieve. The word "cell" comes from the Old English word "cell" which means a small room or chamber. This word is derived from the Latin word "cella" which also means chamber or small room. When combined, "sieve cell" refers to a type of plant cell that is involved in the transport of nutrients and is characterized by its sieve-like structure.
