Google Analytics is a powerful tool that tracks and analyzes website traffic for informed marketing decisions.
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__utmx
Used to determine whether a user is included in an A / B or Multivariate test.
18 months
_ga
ID used to identify users
2 years
_gali
Used by Google Analytics to determine which links on a page are being clicked
30 seconds
_ga_
ID used to identify users
2 years
_gid
ID used to identify users for 24 hours after last activity
24 hours
_gat
Used to monitor number of Google Analytics server requests when using Google Tag Manager
1 minute
__utmb
Used to distinguish new sessions and visits. This cookie is set when the GA.js javascript library is loaded and there is no existing __utmb cookie. The cookie is updated every time data is sent to the Google Analytics server.
30 minutes after last activity
__utmc
Used only with old Urchin versions of Google Analytics and not with GA.js. Was used to distinguish between new sessions and visits at the end of a session.
End of session (browser)
__utmz
Contains information about the traffic source or campaign that directed user to the website. The cookie is set when the GA.js javascript is loaded and updated when data is sent to the Google Anaytics server
6 months after last activity
__utmv
Contains custom information set by the web developer via the _setCustomVar method in Google Analytics. This cookie is updated every time new data is sent to the Google Analytics server.
2 years after last activity
_gac_
Contains information related to marketing campaigns of the user. These are shared with Google AdWords / Google Ads when the Google Ads and Google Analytics accounts are linked together.
90 days
__utma
ID used to identify users and sessions
2 years after last activity
__utmt
Used to monitor number of Google Analytics server requests
10 minutes
Microscopic Photos of Digestive System Tissue Slides 4 years, 4 months ago Esophagus
The muscular tube that joins the throat to the stomach is visible in this image of the esophagus, underscoring its crucial function in food transportation. The layered structure, which includes layers of muscle and mucosa, helps explain how the esophagus uses peristalsis—coordinated muscle contractions—to effectively move food downward. It's intriguing to observe how the structure of this organ allows for both strength and flexibility to manage food passage safely.
The esophagus is a tube that moves food from the mouth to the stomach using muscle contractions. It is lined with layers of cells that protect it and produce mucus to keep it moist and safe from damage.
The esophagus plays a key role in the digestive system by actively moving food from the throat to the stomach through coordinated muscular contractions called peristalsis. Its lining, made of stratified squamous epithelium, helps protect it from abrasion caused by swallowing food. One unique feature of the esophagus is its muscularis externa, which transitions from striated muscle in the upper part to smooth muscle in the lower part, reflecting its dual control by voluntary and involuntary mechanisms.