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According to the sliding filament theory, the myosin (thick) filaments of muscle fibers slide past the actin (thin) filaments during muscle contraction. 3D cartoon and Gaussian surface models, based on PDB 6bnp, white background.
plant Zea Stem C.S. under light mircoscope with white background
Spring flowers series, beautiful Cherry blossom , pink sakura flowers
Fringe tree
Closeup on white flowers of black elder sambucus nigra
Photomicrograph of filamentous blue-green algae, Oscillatoria species. Each band along the stand is one cell. This filament is very short probably having recently parted from a longer one. Filaments are typically many times longer. This algae is mobile, it moves and twists through the water. San Francisco Bay, California, USA. Live specimen. Wet mount, 40X objective, transmitted brightfield illumination. Note - motion blur of live specimen, very shallow depth of field, chromatic aberration and uneven focus are inherent in light microscopy.
Microalgae under microscopic view, green algae, cyanobacteria, phytoplankton, diatom, algae mix collage background
Blooming chestnut tree
Fraxinus caroliniana, the pop ash, Florida ash, swamp ash, Carolina ash, or water ash, is a species of ash tree native from Cuba through the subtropical Southeastern United States from southern Virginia to Texas. It was originally described by the botanist Philip Miller.
Rhododendron
Cross-section Dicot, Monocot and Root of Plant Stem under the microscope for classroom education.
Cork Oak (Quercus suber) tree. Luogosanto. Province of Sassari. Sardinia. Italy.
Reynoutria japonica in bloom
Closeup seeds after blooming time of white Eucalyptus flowers, background with copy space, full frame horizontal composition
single tree with clipping path and alpha channel
Close up of summer tree
Haematococcus pluvialis green and cyst algae under microscopic view - haematocyst, active and resting cells, strong antioxidant astaxanthin
Background of fresh young leaves in springtime with sunlight.
Small white flowers on the shrub. Black elderberry flowers. Large inflorescences with white flowers.
Photomicrograph of two rotifers. Rapidly rotating cilia at top of heads, internal organs visible. Live specimen. Wet mount, 10X objective, transmitted brightfield illumination.
Crataegus azarolus unripe fruit
computer generated 3d tree
Carya ovalis, the red hickory or sweet pignut hickory, is a fairly uncommon but widespread hickory native to eastern North America. It is typically found growing in dry, well drained sandy upland ridges and sloped woodlands from southern Ontario, Canada, and in the United States east to New Hampshire, south to northern Florida west to eastern Texas and north-west to Nebraska.
Sambucus nigra. Common names include elder, elderberry, black elder, European elder, European elderberry and European black elderberry.
flowers of the medicinal elder plant bloom on the bush in summer
Aesculus hippocastanum (horse chestnut) leaves
Representatives of the Lemnaceae, the duckweed family, are well-adapted for use as bioindicators for testing soil and water for toxic substances.  Their rapid multiplication and the simplicity of their anatomy are important advantages for this use.
Flowers of Strawberry Tree (Arbutus unedo). Cinque Terre. Liguria. Italy.
Giant knotweed (Fallopia sachalinensis). Known also as Sakhalin Knotweed also. Another scientific names are Reynoutria sachalinensis and Polygonum sachalinensis.
Hawthorn
Free Images: "bestof:Megalocystidium-Mamximum-Likelihood-Tree.svg Megalocystidium Figure Molecular Phylogenetic analysis of Megalocystidium by the Maximum Likelihood method<br/> The"
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