What's the difference between homoplasmy and plastid?
Homoplasmy
Definition:
(n.) Resemblance between different plants or animals, in external shape, in general habit, or in organs, which is not due to descent from a common ancestor, but to similar surrounding circumstances.
Example Sentences:
(1) There is usually only one mitochondrial DNA population (homoplasmy) within an individual.
(2) Transmission of mutant mtDNA through these three generations did not show any tendency toward homoplasmy.
(3) By following the transmission of a heteroplasmic mitochondrial DNA mutation through four generations of Holstein cows, we have documented that substantial shifts in the levels of heteroplasmy can occur between single mammalian generations, that neutral mitochondrial genotypes can segregate in different directions in offspring of the same female, and that a return to homoplasmy may occur in only two or three generations.
(4) This observation suggests that the nt 11778 mutation observed in this LHON family is relatively new; the observation of both heteroplasmy and apparent homoplasmy of the mtDNA in different family members might reflect the normal progression in the establishment of a mitochondrially inherited mutation.
Plastid
Definition:
(n.) Alt. of Plastide
Example Sentences:
(1) Steady state levels of chloroplast mRNA encoding the core PSII polypeptides remain nearly constant in the light or the dark and are not affected by the developmental stage of the plastid.
(2) These results are discussed in terms of the role of contaminants in the observed synthesis, the "normalcy" of Acetabularia chloroplasts, the synthetic pathways for amino acids in plastids, and the implications of these observations for cell compartmentation and chloroplast autonomy.
(3) Chaperonins (Cpn) are implicated in the folding and assembly of multimeric proteins in plastids and mitochondria of eukaryotes and in prokaryotes.
(4) The N-terminal end of the coding region shows features typical of a stromal-targeting plastid-transit peptide.
(5) However, identification of the methionine bristle domain suggests that chloroplast HSPs also have unique functions or substrates within the special environment of the chloroplast or other plastids.
(6) An in vitro translation system using lysed etioplasts was developed to test if the accumulation of plastid-encoded chlorophyll a apoproteins is dependent on the de novo synthesis of chlorophyll a.
(7) Sperm cells within pollen grains and pollen tubes of alfalfa (Medicago sativa L.) were observed at the ultrastructural level, and their plastid DNA was detected by DAPI (4,6-diamidino-2-phenylindole) staining.
(8) Short pulses of red light induce in etiolated barley seedlings an enhanced synthesis of plastidic benzoquinones and vitamin K1, which can be reverted by subsequent irradiation with short pulses of far-red.
(9) Thus, homologies in the rbcS gene indicate a close phylogenetic relationship between rhodoplasts and the plastids of Chromophyta.
(10) The plastid thylakoid polypeptide patterns obtained from various dark-grown mutants, making large but abnormal chloroplasts, show a correlation between the amount of chlorophyll formed and the amount of a plastid thylakoid polypeptide thought to be associated wtth one of the pigment-protein light-harvesting complexes.
(11) An imperfect association of plastid replication and nucleic acid synthesis is suggested by the lack of stimulation of DNA synthesis by light during plastid replication in the first 8 h of incubation.
(12) Duplicated genes for both the plastid and cytosolic isozymes were localized to genomic regions that possess numerous other redundant sequences.
(13) In contrast, in plastids of dark-grown plants, the 15- to 25-kDa translation intermediates were converted into a 23-kDa polypeptide previously suggested to be a proteolytic product of D1.
(14) All plastid thylakoid bands seen in dark-growing wild-type cells and in mutant W3BUL in which plastid DNA is undetectable, are observed to increase in amount during plastid development.
(15) Pulse-labeling assays revealed a population of short-lived proteins in plastids of dark-grown plants.
(16) The difference in rates of amino acid incorporation between etioplasts and chloroplasts is correlated with the state of development of the plastids.
(17) Distinctive features include a complex cytoskeleton which defines the cell organization and interconnects cell components; trichocysts which resemble those in other cryptoprotists; and two non-photosynthetic plastids.
(18) Somatic hybridization of plants by fusions of protoplasts or by uptake of nuclei and other organelles (plastids, mitochondria) or pure nucleic acids is another useful method.
(19) The alga, normally tentoxin-resistant, was rendered tentoxin-sensitive by mutagenesis of its plastid atpB gene at codon 83.
(20) This clearly indicated a close phylogenetic relationship between the plastids of Rhodophyta and Chromophyta which seem to have evolved independently from the chloroplasts (polyphyletic origin).