the respiratory system in a baby is not well developed and they do respire through mouth too, and so they keep their mouth open.
Your body takes in air through your nose and mouth. There is another interpretation of the original question. "to respire"
By asking you (yes you) if you really need to know that.
The phylum Porifera (sponges) has no anus or mouth. They pass water through their bodies to filter out food particles, but they do not have specialized openings for ingestion or excretion.
Reptiles have 2 body openings. Mouth and an anus.
You Have lymph nodes under your chin as well as your tonsils. However most harmful bacteria that come in through your mouth will be killed my enzymes in your saliva
There are published openings for veterinarians in the biweekly JAVMA journal, as well as on USAJobs.gov. However, most openings for veterinarians in private practice are not advertised formally - they are filled through word of mouth or through contacts with the local vet school.
Cats have a pair of vomeronasal organs on the roof of their moth that help them sniff out a particular scent. Usually cats do not breathe through their mouth.
The tonsils help protect the body from harmful microorganisms that enter through the mouth. They are part of the immune system and function as a first line of defense by trapping pathogens before they can spread further into the body.
They have one according to my science text book.
No, all modern amphibians do not only use their lungs for respiration. They can also respire through their skin and tissues in the lining of their mouth.
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