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Eukaryotes
Eukaryote
(Science: cell biology) organism whose cells have chromosomes with nucleosomal structure and separated from the cytoplasm by a two membrance nuclear envelope and compartmentalisation ...
EUKARYOTES - CELLS WITH PARTS
This is the place to learn about cells with a nucleus and all sorts of organelles. Eukaryotes are what you think of when you think of a classic "cell.
Eukaryotes
Basic structure
The basic eukaryotic cell contains the following:
plasma membrane
glycocalyx (components external to the plasma membrane)
cytoplasm (semifluid) ...
There are several methods used by eukaryotes.
Altering the rate of transcription of the gene. This is the most important and widely-used strategy and the one we shall examine here.
Eukaryotes
The Kingdoms Protista, Fungi, Plants and Animals are the other five kingdoms and they are composed solely of eukaryotic organisms.
eukaryotes
Any member of a group of organisms that contains all plants and animals apart form bacteria and blue-green algae. Their cells possess a membrane-bound nucleus containing the genetic material.
[edit] Eukaryotes
Main article: Eukaryote
An amoeba, a typical eukaryotic microorganism ...
Eukaryotes have 9 doublets (pairs) of microtubules arranged in a circle around 2 central microtubules. This 9 + 2 pattern is characteristic of all eukaryotic cilia and flagella but not those of prokaryotes.
In eukaryotes, a gene often contains altering sequences known as exons (expressed codons) and introns (interrupting codons).
In eukaryotes, the rRNA in ribosomes is organized into four strands, and in prokaryotes, three strands. Eukaryote ribosomes are produced and assembled in the nucleolus.
Cap: All eukaryotes have at the 5' end of their messages a structure called a "cap", consisting of a 7-methylguanosine in 5'-5' triphosphate linkage with the first nucleotide of the mRNA.
intron In eukaryotes, bases of a gene transcribed but later excised from the mRNA prior to exporting from the nucleus and subsequent translation of the message into a polypeptide. PICTURE ...
The viruses of eukaryotes are similar to prokaryote-infecting viruses. Proviruses are viral DNA integrated into the host cell. Some of the DNA viruses can either initiate an infection (lytic in prokaryotes) cycle or can form proviruses.
Chromosomes exist in pairs in higher eukaryotes. (See Chromosome walking.) Chromosome walking. Working from a flanking DNA marker, overlapping clones are successively identified that span a chromosomal region of interest. (See Chromosome.) Cistron.
Artificial chromosomeA vector constructed from host cell chromosomal elements such as origin of replication, telomeres and centromere (in eukaryotes).
Alternative splicing is an important regulatory mechanism in higher eukaryotes1. By recent estimates, at least 30% of human genes are spliced alternatively (Mironov, A.A. and Gelfand, M.S. Proc. 1st Int. Conf.
Many eukaryotes, including stressed plants, insects, deep-sea animals and kidney tubule cells, adapt to environmental variation by making or accumulating diverse inositol derivatives as ‘compatible' solutes.
Eukaryotes - advanced cell type with a nuclear membrane surrounding genetic material and numerous membrane-bound organelles dispersed in a complex cellular structure ...
Many tissue specific enhancers can determine spatial patterns of gene expression in higher eukaryotes. Enhancers can act on promoters over many tens of kilobases of DNA and can be 5' or 3' to the promoter they regulate.
These are: the prokaryotes ("ordinary" bacteria), archaebacteria (thermophilic, methanogenic and halophilic bacteria) and eukaryotes.
Recent evidence strongly suggests that lateral gene transfer involving eukaryotes may be more prevalent than once thought. In some DNA sequences, bacterial or archaeal sequences cluster in clades that are otherwise strictly eukaryotic.
DNA usually occurs as linear chromosomes in eukaryotes, and circular chromosomes in prokaryotes. A chromosome is an organized structure consisting of DNA and histones.
When we divide the organisms that live on this planet, we make a distinction between those that have a nucleus, that are called eukaryotes, and those that don't have a nuclei, which we call prokaryotes.
Eukaryotes include all organisms except viruses, bacteria, and blue-green algae. Compare prokaryote. See chromosomes.
Related Terms:
Nucleus ...
Double stranded RNA (dsRNA): In eukaryotes, it is an accidental byproduct of transcriptional process.
mitochondrion -- Complex organelle found in most eukaryotes; believed to be descended from free-living bacteria that established a symbiotic relationship with a primitive eukaryote.
The formation of new gene combinations; in eukaryotes, may be accomplished by new associations of chromosomes produced during sexual reproduction or crossing over; in prokaryotes, may be accomplished through transformation, conjugation, ...
Histone
A basic protein from eukaryotes (or Archae) which binds to DNA, forming nucleosomes, and packaging the DNA into chromatin.
Histone-like proteins
Proteins from bacteria which bind to DNA, and compact the DNA.
A phylogenetic tree of all living things, based on rRNA gene data, showing the separation of the three domains bacteria, archaea, and eukaryotes as described initially by Carl Woese.
- A nuclear organelle of eukaryotes, associated with the chromosomal site of genes coding for rRNA
Nucleosome
- The basic structural unit of eukaryotic chromosome, composed of an octomer and DNA ...
Unicellular or multicellular photosynthetic eukaryotes that generally lack roots, stems, leaves, conducting vessels, and complex sex organs. Formerly, photosynthetic bacteria were also called algae, but this usage is now obsolete.
AMP-dependent protein kinase A protein kinase, conserved among eukaryotes, that is activated on binding of AMP and inhibited by ATP; consequently, it functions as a cellular fuel gauge, ...
As with eukaryotes, the membrane controls the permeability of the cell and is the major site of energy metabolism.
1. The membrane bound organelle containing the genome of eukaryotes organized into chromosomes.
2. The center portion of an atom which contains the protons and neutrons.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z ...
(e.g., genes, RFLP markers) on a chromosome; the closer together the markers are, the lower the probability that they will be separated during DNA repair or replication processes (binary fission in prokaryotes, mitosis or meiosis in eukaryotes), ...
The pre-tRNA of prokaryotes and eukaryotes has extra nucleotides at the 5' and 3' extremities and in some eukaryotic pre-tRNAs introns are also present.
Archaebacteria A phylum of organisims distinct from both prokaryotes and eukaryotes.
Ascertainment The method by which individuals (and families) come to attention for genetic study.
gonidia - reproductive cells of colonial photosynthetic eukaryotes such as Volvox.
granular/granule cell - most abundant neuron type in the cerebellar cortex of the vertebrate brain.
Kingdom Plantae group of multicellular eukaryotes‚ most of which have chlorophyll and do photosynthesis to make their own food
(planta = plant; probably from plantare = to level the ground for sowing; planus = level‚ flat) ...
A cell or organism with membrane-bound, structurally discrete nucleus and other well-developed subcellular compartments. Eukaryotes include all organisms except viruses, bacteria, and bluegreen algae.
Source : Human Genome Project Information ...
a cell that lacks a membrane-bonded nucleus, does not undergo meiosis, and lacks the structurally complex chromosomes found in eukaryotes
Source: Jenkins, John B. 1990. Human Genetics, 2nd Edition. New York: Harper & Row
...
Nucleus: The cellular organelle in eukaryotes that contains the genetic material.
O ...
ocytes A group of prokaryotes currently classified among the Archaebacteria but possibly a sister group of eukaryotes.
eosinophil White blood cells characterized by the presence of cytoplasmic granules that become stained by an acid dye.
In higher eukaryotes, the conversion of cultured cells to a malignant phenotype--typically through infection by a tumor virus or transfection with an oncogene. (See Transformant, Transformation efficiency.) ...
 See also: Eukaryote, Organ, Cells, Cell, Protein
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