No, prokaryotes do not have mitochondria. Mitochondria are only found in eukaryotic cells. This is also true of other membrane-bound structures like the nucleus and the Golgi apparatus more on these later. One theory for eukaryotic evolution hypothesizes that mitochondria were first prokaryotic cells that lived inside other cells. Over time, evolution led to these separate organisms functioning as a single organism in the form of a eukaryote.
Eukaryotes are organisms whose cells have a nucleus and other organelles enclosed by a plasma membrane. Organelles are internal structures responsible for a variety of functions, such as energy production and protein synthesis. While most eukaryotes are multicellular organisms, there are some single-cell eukaryotes. Within a eukaryotic cell, each membrane-bound structure carries out specific cellular functions.
Here is an overview of many of the primary components of eukaryotic cells. Eukaryotic cells are found in plants, animals, fungi, and protists. Eukaryotes are organisms containing eukaryotic cells. A comparison of plant and animal cells shows that even though eukaryotic cells have membrane-bound nuclei and organelles that carry out many similar functions, they are not all the same. Animal and plant cells are both supported by a cytoskeleton and plasma membrane.
In addition to these structures, plant cells have a supportive cell wall , which is not present in animal cells. Plant cells also have a large central vacuole that supports them. Both plants and animal cells use numerous small vesicles to contain waste, transport materials, and perform many other functions.
In so doing it maintains the chemical balance necessary for the cell to live. The cell membrane regulates the crossing of chemicals in and out of the cell in three ways including:. This means the genetic material DNA in prokaryotes is not bound within a nucleus.
Most prokaryotes are made up of just a single cell unicellular but there are a few that are made of collections of cells multicellular. Scientists have divided the prokaryotes into two groups, the Bacteria, and the Archaea. A typical prokaryotic cell might contain the following parts:. Eukaryotes are organisms made up of cells that possess a membrane-bound nucleus that holds DNA in the form of chromosomes as well as membrane-bound organelles.
Eukaryotic organisms may be multicellular or single-celled organisms. All animals are eukaryotes. Other eukaryotes include plants, fungi, and protists. A typical eukaryotic cell is surrounded by a plasma membrane and contains many different structures and organelles with a variety of functions.
Examples include the chromosomes a structure of nucleic acids and protein which carry genetic information in the form of genes , and the mitochondria often described as the "powerhouse of the cell". Updated 21 Nov. Linares, Daniel M. A typical eukaryotic cell is shown in Figure below. Eukaryotic cells are usually larger than prokaryotic cells, and they are found mainly in multicellular organisms.
Organisms with eukaryotic cells are called eukaryotes , and they range from fungi to people. Eukaryotic cells also contain other organelles besides the nucleus. An organelle is a structure within the cytoplasm that performs a specific job in the cell.
Organelles called mitochondria, for example, provide energy to the cell, and organelles called vacuoles store substances in the cell. Organelles allow eukaryotic cells to carry out more functions than prokaryotic cells can. This allows eukaryotic cells to have greater cell specificity than prokaryotic cells. Ribosomes , the organelle where proteins are made, are the only organelles in prokaryotic cells.
Eukaryotic Cell. Compare and contrast the eukaryotic cell shown here with the prokaryotic cell. What similarities and differences do you see? In some ways, a cell resembles a plastic bag full of Jell-O. Its basic structure is a plasma membrane filled with cytoplasm.
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