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from article Cardiovascular system
Computerized artwork of the human cardiovascular system, including the heart, lungs, and major arteries and veins. (Credit: Science Photo Library RF/Getty Images)
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from article Cardiovascular system
Diagram of the heart and major vessels of a fetus just before birth. Small arrows within the liver indicate alternative blood routes by way of hepatic sinusoids. (Credit: Based on an original drawing by B. M. Patten; copyright © McGraw-Hill…
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from article Cardiovascular system
Single type of circulatory system. (Credit: Based on an original drawing by C. K. Weichert; copyright © McGraw-Hill Education)
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from article Cardiovascular system
Double type of circulatory system in a vertebrate having a four-chambered heart (ventral view). (Credit: Based on an original drawing by C. K. Weichert; copyright © McGraw-Hill Education)
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from article Cardiovascular system
Illustration of the human cardiovascular system, which involves pulmonary circulation and systemic circulation. Red vessels transport oxygenated blood; blue vessels transport deoxygenated blood; and purple vessels are involved in gas exchange.…
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from article Hematologic disorders
Myelophthisic anemia results from a space-occupying lesion in the bone marrow, which hinders hematopoiesis (the process by which the cellular elements of the blood are formed). In this photomicrograph, the bone marrow space is expanded, and the…
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from article Hematologic disorders
Scanning electron micrograph of (top) an elongated, flattened sickle cell and (bottom) a normal red blood cell. (Credit: Callista Images/Image Source/Getty Images)
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from article Hematologic disorders
Colored scanning electron micrograph of round leukocytes from a patient with leukemia. (Credit: Steve Gschmeissner/Science Photo Library)
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from article Allometry
Allometric lines for the mass of some organs across mammal species. (These are best-fit lines: individual species may lie above or below them.) Note that the skeleton is disproportionately heavy in large species (positive allometry), whereas the…
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from article Allometry
Three different types of allometry. Each curve shows the growth allometry of organ size in a different species. The adults of each species show static intraspecific allometry. The circles indicate a particular stage of the life history (for example,…
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from article Electric filter
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from article Electric filter
Passive, lumped-element filters. (a) RC low-pass filter. (b) LC band-pass filter.
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from article Electric filter
Ladder structure. (a) Overall structure with alternating series and shunt arms. (b) LC circuit whose impedance contains both a finite-frequency pole and a zero. Such circuits are used in the series and shunt arms of the ladder structure.
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from article Electric filter
Mechanical filter.
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from article Electric filter
Single-amplifier filters. (a) Low-pass Sallen-Key filter. (b) Low-pass, infinite-gain, single-amplifier filter. (c) Cascade of second-order filter realizations.
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from article Electric filter
Multiple-amplifier filters. (a) State-variable (KHN) filter. (b) Tow-Thomas filter.
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from article Electric filter
Simulated-inductor realization of fifth-order high-pass filter. (a) RLC prototype, normalized for cutoff frequency of 1 rad/s (0.159 Hz). (b) Direct active-RC realization.
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from article Satellite television broadcasting
Direct broadcasting television satellite system.
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from article Fungi
Porcini mushrooms (Boletus edulis) are members of the Basidiomycota division of Fungi. (Credit: Digoarpi/Shutterstock)
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from article Fungi
Spore types (upper illustrations) and structures of parent mycelia (lower illustrations) in fungi.
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from article Fungi
Sporangia of saprophytic Rhizopus. (Credit: Richard Gross; copyright © McGraw-Hill Education)
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from article Fungi
Sexual mechanisms in fungi: (a) gametic copulation; (b) gametangial copulation; (c) gamete-gametangial copulation; and (d) somatic copulation.
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from article Fungi
Colorized scanning electron micrograph of brewer's yeast cells (Saccharomyces cerevisiae). This fungus consists of single vegetative cells, and small daughter cells can be seen budding off from the larger cells. Brewer's yeast is used in the…
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from article Medical bacteriology
Microscopic view of bacterial pneumonia, which is a type of pneumonia caused by bacterial infection. (Credit: Stocktrek Images/Corbis)
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from article Medical bacteriology
Bacteria culture growth on agar medium in a petri dish. (Credit: Sompraaong0042/Shutterstock)
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from article Genetically modified organism (GMO)
Transgenic zebrafish cells. Green fluorescent protein (GFP) is a fluorescent protein first discovered in the jellyfish Aequorea victoria. GFP is commonly used as a reporter of gene expression in other species. Here, GFP is expressed by zebrafish…
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from article Genetically modified organism (GMO)
Genome editing technologies. In particular, targeted nucleases are a powerful tool for precise genome editing in GMOs. Among these tools are (a) transcription activator-like effector nucleases (TALENs), (b) zinc-finger proteins (ZFPs), (c) homing…
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from article Channelrhodopsin
Three-dimensional (3D) protein crystal structure of channelrhodopsin variant C1C2. (Image courtesy of Protein Data Bank 3UG9, Molecular Modeling Database 96737)
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from article Melatonin
Chemical structure of melatonin (C13H16N2O2).
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from article Phospholipases
Sites at which different phospholipases cleave the typical phospholipid phosphatidylcholine. F1 and F2 are long-chain fatty acids esterified at positions 1 and 2 of the glycerol backbone, respectively.
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from article Phospholipases
Mechanisms by which activated receptors coupled to phospholipase C (PLC) through heterotrimeric G proteins produce their physiological responses. Terms: PIP2, phosphatidylinositol bisphosphate; DAG, diacylglycerol; PKC, protein kinase C; IP3,…
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from article Human-factors engineering
Human-factors engineers design modern computer equipment, including ergonomic keyboards and mouse devices, to accommodate the varied physical contours and dimensions of the human hand. (Credit: JG Photography/Alamy)
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from article Human-factors engineering
Human-factors engineering addresses problems related to the design of seats, workplaces, and consoles in terms of a user's physical size, comfort, strength, and visibility. (Copyright © McGraw-Hill Education)
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from article Human-factors engineering
Cognitive engineering and the development of new technology applications.
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from article Human ecology
Shacks and garbage along a dirty river in a slum in Manila, Philippines. Human ecology encompasses how individual people and their communities interact with their particular environment. In many cases, though, humans have created polluted…
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from article Human ecology
Burning of a tropical rainforest in Brazil in order to clear land for animal grazing. (Credit: Barry Barker; copyright © McGraw Hill)
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from article DNA methylation
In humans and other mammals, DNA methylation involves the addition of a methyl group to a cytosine ring, forming methylcytosine. The methylation is carried out by a DNA methyltransferase (DNMT). (Copyright © McGraw-Hill Education)
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from article DNA methylation
Transcriptional silencing via DNA methylation. The methylated configuration blocks proteins that activate gene transcription, preventing them from acting as gene activators. (Copyright © McGraw-Hill Education)
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from article Microtechnique
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from article Microtechnique
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from article Microtechnique
Materials and method for applying cover slip to balsam wholemount. (a) Correct way; notice that the cover slip is held vertically centered over the drop of balsam. (b) Wrong way; this method draws the object to one side. (After P. Gray, Handbook of…
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from article Microtechnique
Making a smear preparation. (a) Place the drop about 1 in. (2.5 cm) from end of slide. (b) Apply a second slide just in front of the drop. (c) Push slide smoothly forward to spread the smear. (After P. Gray, Handbook of Basic Microtechnique, 3d ed.,…
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from article Microtechnique
Rotary microtome produced by the American Optical Co. (From P. Gray, Handbook of Basic Microtechnique, 3d ed., McGraw-Hill, 1964)
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from article Microtechnique
Method of mounting the wax block on the block holder. (After P. Gray, Handbook of Basic Microtechnique, 3d ed., McGraw-Hill, 1964)
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from article Microtechnique
Basic steps in cutting and mounting paraffin ribbons prior to staining. (a) Starting the ribbon. (b) Cutting the ribbon in lengths. (c) Mounting the dry ribbon. (d) Flooding the ribbons. (e) Warming the flooded ribbons to flatten them. (After P.…
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from article Microtechnique
Coplin jars for starting a slide through the reagent series. (After P. Gray, Handbook of Basic Microtechnique, 3d ed., McGraw-Hill, 1964)
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from article Bioorganic chemistry
Vancomycin and an analog that is active against vancomycin-resistant bacteria.
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from article Bioorganic chemistry
Foldamers that mimic proteins.
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from article Bioorganic chemistry
The rate of this intramolecular lactonization, relative to that of intermolecular esterification, mimics the rate increase caused by an enzyme's binding and orienting substrates for a bimolecular reaction.
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from article Bioorganic chemistry
Intramolecular models of enzymatic general acid and general base catalysis. (a) Intramolecular general acid catalysis causes this acetal to hydrolyze at pH 7 more than 107 times faster than the corresponding acetal without the carboxylic acid group.…
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from article Bioorganic chemistry
An antibody raised against the phosphonate analog of a tetrahedral intermediate catalyzes the hydrolysis of cocaine to ecgonine methyl ester.
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from article Bioorganic chemistry
A functionalized cyclodextrin mimics the enzyme RNase by catalyzing the regioselective hydrolysis of a model phosphodiester.
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from article Bioorganic chemistry
Enzyme-catalyzed reactions that have been commercialized as industrial processes.
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from article Bioorganic chemistry
Mechanism of DNA scission by calicheamicin. Reductive or nucleophilic cleavage of the trisulfide triggers conjugate (Michael) addition to the enone, rehybridization of the bridgehead carbon, and Bergman cyclization of the enediyne, generating a…
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from article Type 1 diabetes
One characteristic feature of type 1 diabetes is glomerulosclerosis (Kimmelstiel-Wilson lesion), which involves the scarring or hardening of the glomeruli (blood vessels) in the kidneys. (Copyright © McGraw Hill)
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from article Type 1 diabetes
Stages in the development of type 1 diabetes. (Credit: Type 1 Diabetes TrialNet)
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from article Parathyroid gland
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from article Parathyroid gland
Common positions of human parathyroid glands on the posterior aspect of the thyroid. (After W. H. Hollinshead, Anatomy of the endocrine glands, Surg. Clin. N. Amer., 32(4):1115–1140, 1952)
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from article Parathyroid gland
Section of human parathyroid gland, demonstrating the two main parenchymal cell types. Zenker-formal fixation, Mallory-azan stain. (After D. Bloom and D. W. Fawcett, A Textbook of Histology, 9th ed., Saunders, 1968)
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from article Parathyroid gland
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from article Yeast
Colorized scanning electron micrograph (SEM) of Schizosaccharomyces pombe yeast. This single-celled fungus is studied widely as a model organism for eukaryotic cell division. It is a rod-shaped yeast that grows by elongation at its ends, and it…
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from article Yeast
Cell shapes of yeasts are extremely varied: (a) rectangular; (b) pear-shaped; (c) apiculate; (d) ogival; (e) spherical; (f) globose; (g) ellipsoidal (oval); (h) elongate; (i) tetrahedral. (Copyright © McGraw Hill)
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from article Yeast
Colorized scanning electron micrograph (SEM) of cells of brewer's yeast (Saccharomyces cerevisiae). This yeast consists of single vegetative cells. Small daughter cells can be seen budding off from the larger cells. Saccharomyces cerevisiae ferments…
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from article Yeast
Yeast mycelia: (a) a true septate mycelium showing a break to form an arthrospore; (b) a pseudomycelium. (Copyright © McGraw Hill)
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from article Yeast
Heterothallic (bifactorial) life cycle of a basidiomycetous yeast, Leucosporidium scottii. (Copyright © McGraw Hill)
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from article Yeast
A fluorescent antibody stain reveals the oval budding yeast cells of Candida albicans. This yeast is the most common human fungal pathogen. (Credit: Maxine Jalbert and Leo Kaufman/Centers for Disease Control and Prevention)
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from article Beer
Grains of (a) barley before malting and (b) hop plant. (Credit: U.S. Department of Agriculture)
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from article Beer
Fermentation tanks. (Credit: ClarkandCompany/Getty Images)
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from article Peppermint
Peppermint (Mentha piperita). (Credit: Michael Thompson/Agricultural Research Service, U.S. Department of Agriculture)
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from article Citron
Citron (Citrus medica), including cross sections of the fruit. (Photo courtesy of California Citrus Clonal Protection Program)
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from article Foodborne disease
Trichrome-stained photomicrograph of a Giardia lamblia trophozoite (a growing stage in the life cycle of certain protozoan parasites). This microorganism often causes giardiasis (a diarrheal foodborne illness). (Credit: Melanie Moser/Centers for…
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from article Foodborne disease
A cluster of norovirus particles. (Credit: Charles D. Humphrey/Centers for Disease Control and Prevention)
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from article Foodborne disease
Colored scanning electron micrograph showing Salmonella enterica bacteria (serotype Typhimurium; colorized red) invading an immune cell (colorized yellow). This bacterial species commonly causes food-associated gastroenteritis. (Credit: National…
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from article Foodborne disease
Close-up view of Campylobacter jejuni bacteria. This scanning electron microscope image shows the characteristic spiral (or corkscrew) shape of C. jejuni cells. (Credit: De Wood and Chris Pooley/Agricultural Research Service, U.S. Department of…
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from article Gelatin
Gelatin capsules. (Copyright © Digital Vision/SuperStock)
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from article Gelatin
Gelatin fruit dessert. (Credit: Getty Images/iStockphoto)
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from article Astrapotheria
Skeleton of Astrapotherium magnum. The genus Astrapotherium is known from the late Oligocene to the late Miocene.
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from article Trans fatty acid
Generalized chemical structure of the double bond in natural and common industrial monounsaturated fatty acids (18:1): configuration of the unsaturation site in monounsaturated fatty acids as found as a cis structure in natural fats/oils or as a…
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from article Lycopsida
Lycopodium clavatum, a representative homosporous lycopsid. (a) Sporophyte showing typical rhizomatous growth and paired cones. (b) Microphyllous leaf. (c) Sporophyll bearing a sporangium on the upper surface. (From K. R. Sporne, The Morphology of…
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from article CRISPR/Cas9 gene editing
Acquisition of immunity in the CRISPR/Cas9 system. Bacterial cells that are not immune to a particular bacteriophage and that survive infection acquire immunity through the function of the cas1 and cas2 genes. Through unknown mechanisms, Cas1 and…
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from article CRISPR/Cas9 gene editing
The function of the CRISPR/Cas9 system in bacterial immunity. Bacterial cells that are immune to particular bacteriophage species contain protospacer sequences that match or closely match the bacteriophage genome. (1) The bacterial genome contains…
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from article CRISPR/Cas9 gene editing
The function of the CRISPR/Cas9 system in genome engineering. Multiple methods are used to engineer genomes using the CRISPR/Cas9 system. One common method is illustrated here. (1) An engineered cas9 gene and an engineered crRNA–tracrRNA fusion…
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from article Brain
Magnetic resonance imaging (MRI) is a tool used to scan the brain. Four coronal-view MRI scans of the human brain are shown. (Credit: Shutterstock/AkeSak)
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from article Brain
Midsagittal (midline, medial) section through the human brain. (Credit: C. R. Noback; copyright © McGraw-Hill Education)
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from article Brain
Lateral surface view of the cerebral hemisphere. (Credit: C. R. Noback; copyright © McGraw-Hill Education)
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from article Modeling language
Systems engineering work space.
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from article Modeling language
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from article Modeling language
Component diagram for car window control. The small rectangles signify that this is a component diagram.
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from article Modeling language
Example of deep dependency structure.
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from article Vestibular system
Vestibular sensors are located in the inner ear. (a) Three semicircular canals and two otolith organs (utricle and saccule) detect head movements. Vestibular nerve fibers carry signals (with regular and irregular resting discharges) from the inner…
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from article Vestibular system
Compensation in the vestibulo-ocular reflex (VOR) response and vestibular nuclei (VN) neurons. (a) VOR compensation over time after unilateral removal of the labyrinth of the inner ear (labyrinthectomy) in response to rapid head movements in…
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from article Vestibular system
Organization of the vestibular cerebellum. The five main cerebellar regions that receive vestibular input include (1) lobules I–V of the anterior lobe (yellow), (2) lobules VI and VII, which comprise the oculomotor vermis of the posterior lobe…
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from article Vestibular system
Ascending thalamocortical projections of the vestibular information. VPL = vestibular posterior lateral thalamus, ADN = anterodorsal nucleus of the thalamus, VN = vestibular nuclei. VOR = vestibulo-ocular reflex. VSR = vestibular-spinal reflex.
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from article Marsupialia
Skull and jaws of marsupials. (a) Didelphidae, Didelphis (the carnivorous opossum of North America), Recent, with polyprotodont incisors (I 5/4). (b) Phalangeridae, Trichosurus (the herbivorous opossum of Australia), Recent, with diprotodont…
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from article Marsupialia
Views of the soles of the left hindfoot of marsupials. (a) Didelphidae, Didelphis, representing the five-toed, polydactylous condition. (b) Phalangeridae, Trichosurus, representing the five-toed, syndactylous condition (digits II and III are bound…
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from article Hyperbolic navigation system
Typical grid of hyperbolic lines of position formed by a master (M) and two secondary stations (W and X).
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from article Hyperbolic navigation system
Individual lines of position from a master and two secondaries at location P. γ =LOP crossing angle.
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from article Hyperbolic navigation system
Typical curves of constant horizontal dilution of precision (HDOP) for a master (X) and two secondary stations (X and Y). Numbers give HDOP values of contours.
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from article Pholidota
Pangolin (genus Manis, order Pholidota). (Credit: Wildlife Alliance)
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from article Yersinia
Scanning electron micrograph (color-enhanced) of Yersinia pestis bacteria (yellow) on the proventricular spines of a Xenopsylla cheopis flea (purple). (Credit: National Institute of Allergy and Infectious Diseases)
