sphincter
Infants have two soft openings within the skull called fontanels. These will usually close completely by about the 18 month of age.
Openings in a leaf are called stomata. Stomata are small pores located primarily on the underside of a leaf that allow for gas exchange, such as the intake of carbon dioxide and the release of oxygen and water vapor.
A muscle around an opening may be named by the term "sphincter". Sphincters are circular muscles that can open and close to regulate the flow of substances through various openings in the body, such as the anus or the urinary bladder.
It is called the neuromuscular junction.
Plants breath through stomates. they are microscopic openings covering the leaves that open and close bringing in CO2 and out oxygen. This gives us 29 percent of our oxygen while the other percentage (71) is from phytoplankton
The parotid gland is close to the masseter muscle, which is one of the main muscles responsible for chewing.
You can tell because if you turn them over ( most will play dead) you can see two openings, on a male, the openings are far apart, on a female, the openings are close together, might even look like one!
You can tell if your kitten is a female by looking for two small openings near the tail. If the openings are close together, it's likely a female kitten.
mentralis buccula
All hamsters have 2 openings between their back legs. Females have openings that are very close together and almost look like one openings. Males have openings that are about 5 to 10 millimeters apart.
The close grip lat pulldown primarily targets the latissimus dorsi muscle.
masseter