What's the difference between leaf and stem?

Leaf


Definition:

  • (n.) A colored, usually green, expansion growing from the side of a stem or rootstock, in which the sap for the use of the plant is elaborated under the influence of light; one of the parts of a plant which collectively constitute its foliage.
  • (n.) A special organ of vegetation in the form of a lateral outgrowth from the stem, whether appearing as a part of the foliage, or as a cotyledon, a scale, a bract, a spine, or a tendril.
  • (n.) Something which is like a leaf in being wide and thin and having a flat surface, or in being attached to a larger body by one edge or end; as : (a) A part of a book or folded sheet containing two pages upon its opposite sides. (b) A side, division, or part, that slides or is hinged, as of window shutters, folding doors, etc. (c) The movable side of a table. (d) A very thin plate; as, gold leaf. (e) A portion of fat lying in a separate fold or layer. (f) One of the teeth of a pinion, especially when small.
  • (v. i.) To shoot out leaves; to produce leaves; to leave; as, the trees leaf in May.

Example Sentences:

  • (1) The dumplings could also be served pan-fried in browned butter and tossed with a bitter leaf salad and fresh sheep's cheese for a lighter, but equally delicious option.
  • (2) Subsequently the plant protein was partially purified from leaf extract.
  • (3) In autumn, leaf-heaps composted themselves on sunken patios, and were shovelled up by irritated owners of basement flats.
  • (4) Isolated nuclei from green leaf tissue of tomato plants infected with potato spindle tuber viroid (PSTVd) were bound to microscope slides, fixed with formaldehyde and hybridized with biotinylated transcripts of cloned PSTVd cDNA.
  • (5) The nuclear membrane was highly deformed with a leaf-like profile in cross-section, possibly due to an interaction with the rod-like, condensed chromosomes.
  • (6) The mass of glycolic acid recovered from sunflower leaf tissue was proportional to the amount of tissue extracted.
  • (7) cDNA clones of potato virus X (PVXcp strain), potato virus Y (PVYo strain), potato leaf roll virus (PLRV) and potato spindle tuber viroid (PSTV) were used separately or combined for the detection of the corresponding RNAs in extracts of infected plants.
  • (8) Positive cDNA clones isolated from both a pea leaf and embryo lambda gt11 expression library using an antibody raised against the purified lipoamide dehydrogenase proved to be the product of a single gene.
  • (9) Betel leaf extract at the dose levels used in the present study did not affect the body weight gain among rats.
  • (10) Poison oak, ivy, and sumac dermatitis is a T-cell-mediated reaction against urushiol, the oil found in the leaf of the plants.
  • (11) Leaf TBC was usually third while fiber had the least TBC.
  • (12) Using this estimate, the pure Photosystem I emission spectrum was subtracted from the measured emission spectrum of a flashed leaf to give an emission spectrum representative of pure Photosystem II fluorescence at -196 degrees C. Emission spectra were also measured on flashed leaves which had been illuminated for several hours in continuous light.
  • (13) The effect of 50% methanolic extract (U-ext) from Bearberry leaf on immuno-inflammation was studied by contact dermatitis caused by picryl chloride (PC-CD) in mice.
  • (14) Several antisera from rabbits immunized with tobacco smoke components reacted by immunoprecipitation with tobacco smoke or leaf antigens.
  • (15) DNP treatment reduced ion absorption by leaf tissue.
  • (16) Instead, cell divisions are gradually restricted to the base of the leaf with localized sites of increased division at the preligule region.
  • (17) In the leaf-nosed bat, Macrotus californicus, a 4.5-month period of delayed early embryogenesis (October-March) precedes a 3.5-month period of normal embryogenesis (March-June).
  • (18) Plastic responses in leaf form resulting from ontogenetic or external influences are initiated very early in primordial development and are brought about by effects on the rate and direction of cell division and expansion in different regions of the primordium.
  • (19) Northern blot analysis of infected leaf tissue extracts revealed the presence of an oligomeric series of plus RNAs (of monomer size and greater) but minus RNAs were present only as high molecular weight species of heterogeneous size.
  • (20) And, hey, until Friday morning, most surveillance reform advocates were worried about the Senate ramming through the currently neutered version of the USA Freedom Act as its fig leaf of reform, before going back to business as usual and proposing bills that will give the NSA more power – not less.

Stem


Definition:

  • (v. i.) Alt. of Steem
  • (n.) Alt. of Steem
  • (n.) The principal body of a tree, shrub, or plant, of any kind; the main stock; the part which supports the branches or the head or top.
  • (n.) A little branch which connects a fruit, flower, or leaf with a main branch; a peduncle, pedicel, or petiole; as, the stem of an apple or a cherry.
  • (n.) The stock of a family; a race or generation of progenitors.
  • (n.) A branch of a family.
  • (n.) A curved piece of timber to which the two sides of a ship are united at the fore end. The lower end of it is scarfed to the keel, and the bowsprit rests upon its upper end. Hence, the forward part of a vessel; the bow.
  • (n.) Fig.: An advanced or leading position; the lookout.
  • (n.) Anything resembling a stem or stalk; as, the stem of a tobacco pipe; the stem of a watch case, or that part to which the ring, by which it is suspended, is attached.
  • (n.) That part of a plant which bears leaves, or rudiments of leaves, whether rising above ground or wholly subterranean.
  • (n.) The entire central axis of a feather.
  • (n.) The basal portion of the body of one of the Pennatulacea, or of a gorgonian.
  • (n.) The short perpendicular line added to the body of a note; the tail of a crotchet, quaver, semiquaver, etc.
  • (n.) The part of an inflected word which remains unchanged (except by euphonic variations) throughout a given inflection; theme; base.
  • (v. t.) To remove the stem or stems from; as, to stem cherries; to remove the stem and its appendages (ribs and veins) from; as, to stem tobacco leaves.
  • (v. t.) To ram, as clay, into a blasting hole.
  • (v. t.) To oppose or cut with, or as with, the stem of a vessel; to resist, or make progress against; to stop or check the flow of, as a current.
  • (v. i.) To move forward against an obstacle, as a vessel against a current.

Example Sentences:

  • (1) However, CT will be insensitive in the detection of the more cephalic proximal lesions, especially those in the brain stem, basal cisterns, and skull base.
  • (2) Based on our results, we propose the following hypotheses for the neurochemical mechanisms of motion sickness: (1) the histaminergic neuron system is involved in the signs and symptoms of motion sickness, including vomiting; (2) the acetylcholinergic neuron system is involved in the processes of habituation to motion sickness, including neural store mechanisms; and (3) the catecholaminergic neuron system in the brain stem is not related to the development of motion sickness.
  • (3) The examination of the standard waves' amplitude and latency of the brain stem auditory evoked response (BAEP) was performed in 20 guinea pigs (males and females, weighing 250 to 300 g).
  • (4) A previous trial into the safety and feasibility of using bone marrow stem cells to treat MS, led by Neil Scolding, a clinical neuroscientist at Bristol University, was deemed a success last year.
  • (5) Proliferation of quiescent hematopoietic stem cells, purified by cell sorting and evaluated by spleen colony assay (CFU-S), was investigated by measuring the total cell number and CFU-S content and the DNA histogram at 20 and 48 hours of liquid culture.
  • (6) The last stems from trends such as declining birth rate, an increasingly mobile society, diminished importance of the nuclear family, and the diminishing attractiveness of professions involved with providing maintenance care.
  • (7) Following BHT administration, the alveolar stem cells (type II pneumocytes) proliferate and differentiate according to a biphasic pattern, with proliferative peaks at d 3 and 7.
  • (8) In testing the contribution of the long, curved stem to the torsional stability of uncemented prostheses by comparing it with other stems, the long, curved stem was the most stable, followed by a shorter straight stem, and a short, proximally curved stem.
  • (9) For example, stem pairing with a sequence other than wild-type resulted in normal protein binding in vitro but derepression of protein synthesis in vivo.
  • (10) These results indicate that this population (approximately 0.1% of bone marrow) may contain the pluripotent hematopoietic stem cell.
  • (11) Brain-stem CBF varied the most but did not correlate with clinical signs of brain-stem dysfunction.
  • (12) We infer from these results that endotoxin ameliorates the cyclical changes in blood cell counts by regulating hematopoietic proliferative activity at the stem cell level.
  • (13) The effects of inhibitors of aldehyde dehydrogenase activity on the sensitivity of murine pluripotent hematopoietic stem cells to oxazaphosphorine anticancer agents, e.g.
  • (14) Three strains of fluorescent pseudomonads (IS-1, IS-2, and IS-3) isolated from potato underground stems with roots showed in vitro antibiosis against 30 strains of the ring rot bacterium Clavibacter michiganensis subsp.
  • (15) This has stemmed from an inadequate understanding of the mechanisms involved in the formation and propagation of this condition.
  • (16) We therefore think that the detailed examination of CALLA(-) non-T non-B ALL cells using myeloid specific antibodies is helpful in clarifying the characteristics of myeloid precursors and the common bipotential stem cell of lymphoid and myeloid progenitors.
  • (17) Imaging studies had shown no change in his brain stem lesion, which at autopsy was found to be a focal collection of fibrillary astrocytes.
  • (18) These cells were hypothesized to be the stem cells for the corneal epithelium.
  • (19) Auditory brain stem potentials (ABP) were recorded in 27 patients with Bell's palsy during the early phase of the disease and 1-3 months later.
  • (20) The results indicate that stimulation of trigeminal subnucleus caudalis, a brain stem region that processes nociceptor afferent information, evokes a prompt increase in plasma ACTH.