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kafirin: a storage protein of sorghum phys >>> Table 15
kanamycin: an aminoglycoside antibiotic; a kanamycin resistance is used as a selection marker in genetic experiments phys biot >>> kanamycin-resistant tissue
kanamycin-resistant tissue: tissue that is resistant to the lethal effects of the aminoglycoside antibiotic, kanamycin; some cloning vectors have
a kanamycin-resistant gene as a selectable marker biot
karyogamy: the fusion in a cell of haploid (n) nuclei to form a diploid (2n) cyto
karyogenesis:
formation of the nucleus (the central structure) of a cell—the smallest, most basic unit of life that is capable of existing by itself; karyogenesis comes from the Greek word karyon meaning “nucleus,” and the Greek word genesis meaning “production”; in a narrow sense, the division of the cell nucleus is distinguished from cytoplasmic division or cytokinesis; it represents a system by which the genetic information contained in the chromosomes of eukaryotes is distributed to the daughter nuclei, which are generally identical to the mother cell nucleus cyto
karyogram >>> idiogram
karyology: the study of the nucleus and its components cyto
karyolysis: the disappearance of the interphase nucleus during karyogenesis cyto
karyosome: any of several masses of chromatin in the reticulum of a cell nucleus cyto
karyostasis: the stage of cell cycle in which there is no visible dividing activity of the nucleus, but a metabolic and synthetic activity cyto phys
karyotype: the entire chromosomal complement of an individual cell or individual, which may be observed during mitotic metaphase cyto
keel: the main nerve of, for example, the wheat glume, shaped somewhat like a keel of a boat; in legumes also a boatlike formation of the flower bot
keel flower: boatlike shape of a flower (e.g., in legumes such as pea) bot
keiki: a vegetative offshoot formed at a node (e.g., in some orchids) bot
kernel: a whole grain or seed of a cereal plant or the part of the seed inside the pericarp bot
ketone: any of a class of organic compounds containing a carbonyl group, CO, attached to two alkyl groups, as CH3COCH3 chem
key gene >>> oligogene
killing frost: a sharp fall in temperature that damages a plant so severely as to cause its death env phys
kilning: the heating and/or drying process used in the production of malt to stop germination and kill the grain prep
kilobases (kb):
1,000 base pairs/bases in a single- or double-stranded nucleic acid, which is used as a common unit of length in molecular genetics gene >>> measures
kilogram: equals 1,000 grams >>> measures
kilometer: equals 1,000 meters >>> measures
kinase: an enzyme that catalyzes reactions involving the transfer of phosphates from a nucleoside triphosphate (e.g., ATP) to another substrate phys
kinetin (6-fururylaminopurine):
a degradation product of animal DNA, which does not occur naturally and which has properties similar to those of cytokinins; applied to certain leaves, kinetin delays senescence in its vicinity and attracts nutrients chem phys
kinetochore:
a dense, plaquelike area of the centromere region of a chromatid, to which the microtubules of the spindle attached during cell division cyto >>> centromere >>> Figure 11
kinin >>> cytokinin
kinship >>> coancestry
KJELDAHL method: a technique often used for the quantitative estimation of the nitrogen content of plant material (e.g., of cereal grains) meth
KLENOW fragment:
large fragment of DNA polymerase I after proteolytic digestion; it lacks 5' to 3' exonuclease activity and can therefore not be used for nick translation but is very useful for filling-in reactions and DNA sequencing by the SANGER method biot
klon >>> clone
kneading: to work dough into a uniform mixture by pressing, folding, and stretching meth
knob:
a heavily stainable and quite a big chromomere observed along a chromosome of some plants (e.g., in maize it is used as a marker in pachytene analysis) cyto >>> chromomere
knot: a lump or swelling in or on a part of a plant (e.g., the node of grass) bot
KOEHLER illumination: illumination optics resulting in the image of the light source being out of focus at the specimen plane; it provides
homogeneous illumination of the specimen micr
KORNBERG enzyme >>> DNA polymerase I
KOSAMBI formula:
recombination fractions and map distances correspond only over relatively short recombinational distance; as genetic distance increases, the probability of a second (and correcting) recombination also increases, hence the measured recombination for two loci is less than would be apparent if a third intervening locus were present; various mapping functions have been suggested to permit single recombination fractions to be converted to map distances; KOSAMBI presented the simplest and probably most general functions, which is given as: x = 25 logn [(1 + 2y)/(1 – 2y)]; x is the map distance (cM) corresponding to the recombination fraction, y; for example, if the recombination value is 0.05 then the distance amounts 5 cM, is the value 0,1 then the distance is 10.1 cM, etc. gene
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