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Bacterial multidrug efflux pumps (E-CmeB) expel antibiotics  from inside the bacterium (bottom): ciprofloxacin (yellow), chloramphenicol (violet),  ampicillin (red).
A model of an Enhanceosome protein complex binding to a strand of DNA. This enhanceosome reacts to infection by viruses by accelerating the production of human interferon and triggering the defenses of the immune system.
Cell membrane structure background, 3d rendering. Digital drawing.
Bacteria pathogen - 3d rendered microbiology image. Illustrate of Lactobacillus Bulgaricus Bacteria, Microbacterium Tuberculosis Bacteria (MTB). Medical research, health-care concept. SEM (TEM) scanning view
3D cartoon model, secondary structure color scheme, PDB 5lb8, white background
Nourish hair of shampoo or serum. Repair damaged hair concept, 3d rendering.
Human Morula Cell, Solid Ball of Cells Resulting from Division
orange: RNA primer; red: RNA template; light blue: proofreading riboexonuclease; mid blue: helicase; dark blue: RNA directed RNA polymerase; violet: non structural proteins (NSPs).
3d rendering of Easter eggs background
Lily leaf c.s. under microscope
Bacteria medical illustration - 3d rendered microbiology image. Illustrate of Lactobacillus Bulgaricus Bacteria, Microbacterium Tuberculosis Bacteria (MTB). Medical research, health-care concept. SEM (TEM) scanning view
Cyclin is a family of proteins that controls the progression of a cell through the cell cycle by activating cyclin-dependent kinase (CDK) enzymes or group of enzymes required for synthesis of cell cycle. 3D cartoon model, PDB 2i53, white background.
Liver Fluke Section under light microscope with white background
Cell Membrane and Molecules, 3d rendering. Computer digital drawing.
Bubbles background
After dopamine binding, the dopamine receptor changes his shape and binds the inactive G protein.The G protein expels its GDP molecule replacing it by GTP. and falls into two pieces. The Galpha subunit binds to and activates the enzyme adenylyl cyclase, which produces then cyclic AMP spreading a signal through the cell.
Green and blue paper clips and one yellow paper clip on a blue background.
Probiotic bacteria, Lactobacillus , 3d illustration.
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.
Nivolumab is an anti-cancer medication used to treat several types of cancer. 3D cartoon and molecular surface model, entity id color scheme, PDB 5ggr, white background
Squash preparation of stained onion root tip cells showing various stages of mitosis. Differential interference contrast optics on a Leica microscope, Image taken with the X40 objective lens.  Depth of focus is extremely shallow (just a few microns).  Differential interference contrast results in an optical slice horizontally through the specimen providing maximum possible resolution at this magnification and good contrast. Chromatic abberation is inevitable in light microscopy, but has been kept to a minimum in this image.
Biological protein and molecule, 3d rendering. 3D illustration.
A model of a strand of DNA. Isolated on black.
Cystic fibrosis transmembrane conductance regulator  (CFTR) allows negatively-charged ions, such as chloride and bicarbonate, to pass through the membrane of lung epithell cells. Malfunction leads to cystic fibrosis. Left: inactive form. ATP (red)
Bacteria medical illustration - 3d rendered microbiology image. Illustrate of Lactobacillus Bulgaricus Bacteria, Microbacterium Tuberculosis Bacteria (MTB). Medical research, health-care concept. SEM (TEM) scanning view
Chain of amino acid or bio molecules called protein - 3d illustration
plant Leaf of Nerium indicum T.S. under light mircoscope with white background
B-chain pentamer and A-chain subunit (green), 3D cartoon and Gaussian surface model, white background
Photomicrograph of rotifer. Rapidly rotating cilia at top of head, internal organs visible. Live specimen. Wet mount, 40X objective, transmitted brightfield illumination.
Free Images: "bestof:Structure cobl.jpg en Structure of Cordon-bleu protein with characteristic domains Own Feux04 08 06 2009 Unidentified biology diagrams"
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