Unlike humans and animals, plants use separate systems to transport food and water - the heavily reinforced xylem for transporting water and the phloem system, with its own built in filters (sieve pla...

A light micrograph of a thin slice through a cup fungus called Peziza. It grows on decaying wood and organic matter and reproduces itself by producing ascospores. This section shows the fungus' spore ...

Colorized light micrograph of Aggregatibacter actinomycetemcomitans colonies. A. actinomycetemcomitans is a Gram-negative bacteria commonly found to cause infections of the oral cavity and often isola...

Colorized light micrograph of Aggregatibacter actinomycetemcomitans colonies. A. actinomycetemcomitans is a Gram-negative bacteria commonly found to cause infections of the oral cavity and often isola...

Bacteria imaged inside the intestines of live zebrafish (Danio rerio) larvae, 5-6 days post-fertilization. The bacteria were engineered to constitutively express Green Fluorescent Protein (GFP), or dT...

Time-lapse experiments showing deltorphin II (100 nM; a selective agonist)-induced internalization of delta-opioid receptor–enhanced GFP (DOR-EGFP; green) receptors expressed in HEK 293 cells. The C...

This time series stack shows an amoeba (Dictyostelium discoideum) trying very hard to ingest a yeast cell (Saccharomyces cerevisiae) that is slightly too large. (The yeast cell is a mutant with an elo...

This is a region of a (semithin) longitudinal section of onion root taken from the meristematic zone; this is the undifferentiated region of plant tissue from which new cells are formed. Therefore, it...

This light micrograph shows the outside edge of two seminiferous tubules of a mouse testis. This section is a 1um thick transverse section, stained with toluidine blue to highlight the cells, with the...

A human (Homo sapien) cheek cell smeared on a coverslip and imaged by birghtfield, phase contrast and differential interference contrast (DIC) microscopy. Images were acquired on a Zeiss Axiovert 200M...