Taste

Prepare your palettes for a taste of taste.

Taste – or gustation – is the one of the traditional five senses along with sight, hearing, touch, and smell. Taste usually refers to the ability to detect flavor, although smell, texture, temperature, and sight are also contributing factors. Humans experience taste through sensory organs called taste buds (or gustatory calyculi), located on the upper surface of the tongue on raised protrusions called papillae. Fungiform papillae are mushroom-shaped, and found on the tip and sides of the tongue; circumvallate papillae are the ten to fourteen dome-shaped dots at the back of the tongue; and foliate papillae appear on the sides of circumvallate papillae and the sides of the base of the tongue. Paintbrush-like filiform papillae are most common, but sense texture and touch rather than taste. Although the widely taught taste map implies taste is localized to certain parts of the tongue, taste-perception is evenly distrusted and all tasting papillae can sense every basic taste.

Photosynthesis

Today on learnalittle, learn how your food feeds itself with a look at photosynthesis.

Photosynthesis is a chemical process that uses sunlight to convert carbon dioxide and water into sugars, usually releasing oxygen as a byproduct. Land plants are the most widely known photoautotrophs (they produce energy from sunlight), along with algae and certain bacteria. Though only a handful of organisms use photosynthesis, all life on earth depends on this process. Cyanobacteria first appeared 3,000,000,000 years ago, and gradually oxygenated the planet, allowing complex aerobic (oxygen-breathing) organisms to evolve. Likewise, photoautotrophs serve as the basic terrestrial food source.

Batteries

Make sure your laptop is fully charged, because today’s learnalittle is all about batteries.

A battery reacts two different kinds of metal to convert stored chemical energy into electricity through a series of ionic reactions. Batteries produce a strong, consistent current of electricity, ideal for powering electronic devices in a closed electrical circuit.