Rat Stomach Tissue
The digital image featured in the above section is a three-dimensional reconstruction of rat stomach fundus tissue stained with Alexa Fluor 350 (wheat germ agglutinin; lectins), Alexa Fluor 568 (phalloidin; actin), and SYTOX Green (nuclei). The muscular contractions of the stomach wall churn food, reducing the volume of the fundus, before food is able to loop around it and the body of the stomach. Chewed food mass called boluses are converted into chyme, or partially digested food, which after passing through the pyloric sphincter and into the duodenum, is extracted of nutrients and digested.