Geranium
Pelargonium
Plant Dormancy
Plantago
Grassland responses to global environmental changes suppressed by elevated CO2. (1/10)
Simulated global changes, including warming, increased precipitation, and nitrogen deposition, alone and in concert, increased net primary production (NPP) in the third year of ecosystem-scale manipulations in a California annual grassland. Elevated carbon dioxide also increased NPP, but only as a single-factor treatment. Across all multifactor manipulations, elevated carbon dioxide suppressed root allocation, decreasing the positive effects of increased temperature, precipitation, and nitrogen deposition on NPP. The NPP responses to interacting global changes differed greatly from simple combinations of single-factor responses. These findings indicate the importance of a multifactor experimental approach to understanding ecosystem responses to global change. (+info)Multiple major increases and decreases in mitochondrial substitution rates in the plant family Geraniaceae. (2/10)
BACKGROUND: Rates of synonymous nucleotide substitutions are, in general, exceptionally low in plant mitochondrial genomes, several times lower than in chloroplast genomes, 10-20 times lower than in plant nuclear genomes, and 50-100 times lower than in many animal mitochondrial genomes. Several cases of moderate variation in mitochondrial substitution rates have been reported in plants, but these mostly involve correlated changes in chloroplast and/or nuclear substitution rates and are therefore thought to reflect whole-organism forces rather than ones impinging directly on the mitochondrial mutation rate. Only a single case of extensive, mitochondrial-specific rate changes has been described, in the angiosperm genus Plantago. RESULTS: We explored a second potential case of highly accelerated mitochondrial sequence evolution in plants. This case was first suggested by relatively poor hybridization of mitochondrial gene probes to DNA of Pelargonium hortorum (the common geranium). We found that all eight mitochondrial genes sequenced from P. hortorum are exceptionally divergent, whereas chloroplast and nuclear divergence is unexceptional in P. hortorum. Two mitochondrial genes were sequenced from a broad range of taxa of variable relatedness to P. hortorum, and absolute rates of mitochondrial synonymous substitutions were calculated on each branch of a phylogenetic tree of these taxa. We infer one major, approximately 10-fold increase in the mitochondrial synonymous substitution rate at the base of the Pelargonium family Geraniaceae, and a subsequent approximately 10-fold rate increase early in the evolution of Pelargonium. We also infer several moderate to major rate decreases following these initial rate increases, such that the mitochondrial substitution rate has returned to normally low levels in many members of the Geraniaceae. Finally, we find unusually little RNA editing of Geraniaceae mitochondrial genes, suggesting high levels of retroprocessing in their history. CONCLUSION: The existence of major, mitochondrial-specific changes in rates of synonymous substitutions in the Geraniaceae implies major and reversible underlying changes in the mitochondrial mutation rate in this family. Together with the recent report of a similar pattern of rate heterogeneity in Plantago, these findings indicate that the mitochondrial mutation rate is a more plastic character in plants than previously realized. Many molecular factors could be responsible for these dramatic changes in the mitochondrial mutation rate, including nuclear gene mutations affecting the fidelity and efficacy of mitochondrial DNA replication and/or repair and--consistent with the lack of RNA editing--exceptionally high levels of "mutagenic" retroprocessing. That the mitochondrial mutation rate has returned to normally low levels in many Geraniaceae raises the possibility that, akin to the ephemerality of mutator strains in bacteria, selection favors a low mutation rate in plant mitochondria. (+info)Genome-wide analyses of Geraniaceae plastid DNA reveal unprecedented patterns of increased nucleotide substitutions. (3/10)
(+info)Identification and characterization of the water gap in physically dormant seeds of Geraniaceae, with special reference to Geranium carolinianum. (4/10)
(+info)Synorganisation without organ fusion in the flowers of Geranium robertianum (Geraniaceae) and its not so trivial obdiplostemony. (5/10)
(+info)Extreme reconfiguration of plastid genomes in the angiosperm family Geraniaceae: rearrangements, repeats, and codon usage. (6/10)
(+info)The uneven phylogeny and biogeography of Erodium (Geraniaceae): radiations in the Mediterranean and recent recurrent intercontinental colonization. (7/10)
(+info)The mechanics of explosive dispersal and self-burial in the seeds of the filaree, Erodium cicutarium (Geraniaceae). (8/10)
(+info)I'm sorry for any confusion, but "Geraniaceae" is not a medical term. It is a taxonomic category in botany, referring to the family of flowering plants that includes geraniums, pelargoniums (often also called geraniums in common language), and several other related genera.
If you have any medical terms or concepts you'd like me to define or explain, I'd be happy to help!
I'm sorry for any confusion, but the term "Geranium" is not a medical term. It is a common name used to refer to plants in the genus Pelargonium, which are often grown as ornamental flowers. If you have any questions about a medical issue or a specific term, I'd be happy to try and help answer those for you!
"Pelargonium" is not a term that has a medical definition. It is the name of a genus of flowering plants, commonly known as geraniums, which are often used in horticulture but do not have direct relevance to medical terminology or practice.
'Plant dormancy' is not a term that has a direct medical definition, as it is related to the field of botany rather than medicine. However, I can certainly provide a definition for you:
Plant dormancy is a state of suspended growth and development in plants, typically in response to adverse environmental conditions such as cold temperatures, dryness, or short day length. During this period, the plant's metabolic activity slows down, and it becomes less responsive to external stimuli. Dormancy allows the plant to survive periods of environmental stress and conserve energy until more favorable conditions return.
Examples of plant dormancy include the seed coat preventing germination until it is broken down by environmental factors or the buds on deciduous trees not growing during winter months when temperatures are too low for growth. While this term may not have a direct medical application, understanding plant dormancy can be important in areas such as agriculture and horticulture.
"Plantago" is the genus name for a group of plants commonly known as plantains. There are several species within this genus, including Plantago major (common plantain) and Plantago lanceolata (narrow-leaved plantain), which are found in many parts of the world. These plants have been used in traditional medicine for their alleged healing properties, such as soothing skin irritations, reducing inflammation, and promoting wound healing. However, it is important to note that the medical community's scientific evidence supporting these claims is limited, and further research is needed before any definitive health benefits can be attributed to Plantago species.
A genome is the complete set of genetic material present within an organism. In eukaryotic cells, which include plants, animals, and other complex life forms, the genome is divided into several compartments, including the nucleus (where most of the genetic material is housed) and the plastids (which include chloroplasts in plant cells).
A plastid genome, also known as a plastome, is the genetic material found within a plastid. Plastids are organelles found in the cells of plants, algae, and some protists that are involved in various metabolic processes, including photosynthesis. The plastid genome is typically a circular molecule of DNA that contains genes encoding for proteins, ribosomal RNA (rRNA), and transfer RNA (tRNA) that are necessary for the function and maintenance of the plastid.
The plastid genome is relatively small compared to the nuclear genome, typically ranging from 120-160 kilobases in length. The gene content and organization of plastid genomes are highly conserved across different plant species, making them useful tools for studying evolutionary relationships among plants. Additionally, because plastids are maternally inherited in many plant species, the plastid genome has been used to study patterns of maternal inheritance and hybridization in plants.
DNA, or deoxyribonucleic acid, is the genetic material present in the cells of all living organisms, including plants. In plants, DNA is located in the nucleus of a cell, as well as in chloroplasts and mitochondria. Plant DNA contains the instructions for the development, growth, and function of the plant, and is passed down from one generation to the next through the process of reproduction.
The structure of DNA is a double helix, formed by two strands of nucleotides that are linked together by hydrogen bonds. Each nucleotide contains a sugar molecule (deoxyribose), a phosphate group, and a nitrogenous base. There are four types of nitrogenous bases in DNA: adenine (A), guanine (G), cytosine (C), and thymine (T). Adenine pairs with thymine, and guanine pairs with cytosine, forming the rungs of the ladder that make up the double helix.
The genetic information in DNA is encoded in the sequence of these nitrogenous bases. Large sequences of bases form genes, which provide the instructions for the production of proteins. The process of gene expression involves transcribing the DNA sequence into a complementary RNA molecule, which is then translated into a protein.
Plant DNA is similar to animal DNA in many ways, but there are also some differences. For example, plant DNA contains a higher proportion of repetitive sequences and transposable elements, which are mobile genetic elements that can move around the genome and cause mutations. Additionally, plant cells have cell walls and chloroplasts, which are not present in animal cells, and these structures contain their own DNA.