This photograph shows the large macronucleus and the thin cell membrane covered with cilia (X820). (medscape.com)
The membranellar band completely wraps around the anterior of the cell, all of the oral cilia coordinate to form a single metachronal wave, the macronucleus is re-nodulated, and the cell resumes normal feeding activity. (elifesciences.org)
Ciliated protozoans (Phylum Ciliophora) are characterized by the presence of cilia - used for locomotion, and the presence of two types of nuclei: a somatic nucleus - macronucleus (MAC) - which provides templates for the transcription of all genes required for vegetative growth, and a genetic nucleus - micronucleus (MIC) - used for the exchange of meiotic products during sexual reproduction. (pomona.edu)
Conjugation3
During conjugation, the macronucleus disintegrates, and a new one is formed by karyogamy of the micronuclei. (wikipedia.org)
In addition to its involvement in asexual reproduction, the macronucleus also plays a role in the phenomenon of conjugation, a sexual process unique to Paramecium. (philosophynews.com)
After two Oxytricha perform sexual conjugation, the old macronucleus essentially disappears and a new one is formed from the contents of the micronucleus during development of the new ciliate. (icr.org)
Micronuclei7
The macronuclei of both cells are degraded and then regenerated by fusion of the micronuclei. (philosophynews.com)
Specifically in Stentor 's case, it has numerous small micronuclei that control reproduction and a single, giant, string-like macronucleus that manages its regular functions. (listverse.com)
Formation of multiple micronuclei, which divide mitotically, was observed in cells with a single macronucleus, indicating a defect in early cytokinesis. (bioone.org)
In cells lacking profilin, micronuclei were not positioned at their normal site on the surface of the macronucleus and phagocytosis was defective. (bioone.org)
Paramecium contains two diploid (2n) germline micronuclei (MIC) and a polyploid (800n) somatic macronuclei (MAC). (uni-frankfurt.de)
A large, macronucleus is essential for its survival, while one or two smaller micronuclei are necessary for sexual reproduction. (microscopyu.com)
In macronuclei, DNA molecules contain contiguous sequences representing genes, while in micronuclei genes are broken into fragments that are shuffled, separated by non-coding sequences, and some of the gene fragments are even inverted. (ixxi.fr)
Micronucleus5
Unlike the micronucleus, which is involved in sexual reproduction and genetic exchange, the macronucleus is involved in the daily metabolic activities of the cell. (philosophynews.com)
The macronucleus is larger and more elongated than the micronucleus and contains multiple copies of the genome, known as macronuclear DNA. (philosophynews.com)
The micronucleus is dense and compact and used for reproduction while the macronucleus is dramatically rearranged, amplified, and used for the creature's standard daily living. (icr.org)
As it turns out, the germline genome of the micronucleus is fragmented into over 225,000 precursor DNA segments that are massively and precisely rearranged (unscrambled) during the construction of the new macronucleus and its nanochromosomes (most of which contain only one gene each). (icr.org)
Polyploid2
Macronuclei are polyploid and undergo direct division without mitosis. (wikipedia.org)
Both fragments are able to regenerate because the elongated macronucleus that is divided into both halves during surgery is highly polyploid, ensuring that each half-cell retains many copies of the genome. (elifesciences.org)
Tetrahymena1
Some cells with the antisense disruption contained multiple macronuclei, which in Tetrahymena may indicate a function late in cytokinesis. (bioone.org)
Molecules1
2002 ) Topological organization of DNA molecules in the macronucleus of hypotrichous ciliated protozoa. (academictree.org)
Ciliates1
A macronucleus (formerly also meganucleus) is the larger type of nucleus in ciliates. (wikipedia.org)
Chromosomes2
Macronuclei contain hundreds to thousands of chromosomes, each present in many copies. (wikipedia.org)
The authors of the report state that a 'notable feature arising from this radical genome architecture is that a single MDS [macronucleus destined sequence] in the MIC may contribute to multiple, distinct MAC [macronucleus] chromosomes. (icr.org)
Sequences2
This process uses specialized pointer sequences that flank the macronucleus-designated fragments as a type of encryption and addressing system. (icr.org)
A new model for the identification and elimination of DNA sequences from the developing macronucleus has been published. (ciliate.org)
Nucleus1
The macronucleus is a prominent feature of Paramecium, serving as the primary nucleus responsible for controlling gene expression and cellular functions. (philosophynews.com)
Through its role in gene expression and regulation, the macronucleus enables Paramecium to respond to various stimuli, including changes in temperature, pH, and nutrient availability. (philosophynews.com)
By modulating the expression of specific genes, the macronucleus allows Paramecium to adjust its metabolism, behavior, and morphology in response to environmental cues. (philosophynews.com)
In summary, the macronucleus is a vital organelle within Paramecium cells that controls gene expression, cellular functions, reproduction, cellular differentiation, and environmental adaptation. (philosophynews.com)
Understanding the role of the macronucleus provides valuable insights into the biology and physiology of Paramecium and sheds light on the remarkable capabilities of these single-celled organisms. (philosophynews.com)
At the level of this section the macronucleus, cytopharyngeal tube, food vacuoles, and perioral membranelle are evident. (cellimagelibrary.org)
Gene3
This unique structure allows for rapid gene expression and facilitates the macronucleus' role in regulating various cellular processes. (philosophynews.com)
Macronucleus transformation was achieved by biolistic bombardment and gene replacement through phenotypic assortment, using paromomycin as the selective agent. (conicet.gov.ar)
Some micronuclear genes have their MDSs present in a permuted order, compared to the functional gene in the macronucleus. (pomona.edu)
Significance2
By understanding the functions and significance of the macronucleus, we can gain valuable insights into the biology and physiology of these fascinating microorganisms. (philosophynews.com)
3 While scientists previously understood that the genome of this creature underwent a dramatic reorganization, they did not understand the full significance of the phenomena, because only the macronucleus has been completely sequenced. (icr.org)
Genetic2
This phenomenon, known as genomic DNA processing, ensures that only essential genetic information is retained and expressed in the macronucleus. (philosophynews.com)
During binary fission, the macronucleus undergoes a process of fragmentation and division that results in the equal distribution of genetic material between daughter cells. (philosophynews.com)
Cell1
The macronucleus is closely associated with this process and determines the developmental fate of the cell. (philosophynews.com)
Cells1
Feulgen microspectrophotometry shows the macronuclei of these cells to have been stopped at a point prior to DNA replication (G1 stage). (rupress.org)
Completely1
By 6 hr, the mouthparts are completely formed and the macronucleus is fully condensed. (elifesciences.org)
Somatic1
His Macronucleus research integrates issues from RNA splicing and Somatic cell. (research.com)
Polyploid macronucleus1
The polyploid macronucleus found in ciliates divides amitotically. (majlis-news.net)
Characteristic2
has a characteristic horseshoe shaped macronucleus. (ncvetp.org)
while the macronucleus divides by splitting without the characteristic mitotic apparatus. (biotheories.com)
Ciliate1
What is the function of the ciliate macronucleus? (sage-answer.com)
Cyst1
This photograph demonstrates a thick cyst wall and a large macronucleus (X820). (medscape.com)
Mitosis1
Macronuclei are polyploid and undergo direct division without mitosis. (wikipedia.org)
Localizes1
Cre can be expressed in Tetrahymena and localizes to the macronucleus where it induces precise recombination at two loxP sequences in direct orientation in the Tetrahymena macronuclear chromosome. (biomedcentral.com)
Time1
and that the percentage then began to decrease from 300 to 390 minutes, at which time only 25 per cent of the macronuclei were labeled. (rupress.org)
Present1
Macronuclei contain hundreds to thousands of chromosomes, each present in many copies. (wikipedia.org)
Field1
David M. Prescott works in the field of Gene, focusing on Macronucleus in particular. (research.com)
Note1
Note the darkly stained, bean shaped macronucleus. (cdc.gov)