Are glands in human made of muscles?

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Glands are not composed of muscle tissue; rather, they are specialized tissues that secrete substances. Secretions from glands do not get squeezed out by muscle contractions. For example, skunks have glands near their anus that store a foul-smelling fluid in pouches with muscle walls, which contract to expel the fluid. In contrast, glands like the thyroid and adrenal glands secrete hormones directly into the bloodstream without muscle involvement. The pancreas functions as both an endocrine and exocrine gland, producing digestive enzymes and hormones, but again, muscle tissue is not part of the gland itself. The confusion arises from a biology textbook that inaccurately suggests muscles are involved in glandular secretion. External muscle contractions can help move secretions along, but they do not originate from the glands themselves. The discussion highlights the need for clarity in educational materials regarding the anatomy and function of glands.
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Is it true that glands made of muscles and these are the muscles which squeezes out secretion from the glands?
 
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No. Smooth and striated muscle tissue is not part of a gland. Secretions do not get squeezed out
of glands. Skunks secrete a horrible smelling fluid from glands near the anus. It is stored in pouches with a muscle wall around them. Contraction of the muscle wall squirts out the fluid. Skunks have pretty good aim BTW.

Example: In some contexts you could consider your stomach as secreting HCl or digestive enzymes. But it is not a gland. And it does not squeeze out secretions.
https://en.wikipedia.org/wiki/Stomach

Where did you read this? It is really very hard to give decent answers to questions like yours without context.

What I mean: Please give us a sample of the text that led you to ask the question. Thanks.
 
jim mcnamara said:
No. Smooth and striated muscle tissue is not part of a gland. Secretions do not get squeezed out
of glands. Skunks secrete a horrible smelling fluid from glands near the anus. It is stored in pouches with a muscle wall around them. Contraction of the muscle wall squirts out the fluid. Skunks have pretty good aim BTW.

Example: In some contexts you could consider your stomach as secreting HCl or digestive enzymes. But it is not a gland. And it does not squeeze out secretions.
https://en.wikipedia.org/wiki/Stomach

Where did you read this? It is really very hard to give decent answers to questions like yours without context.

What I mean: Please give us a sample of the text that led you to ask the question. Thanks.
I have read it in my biology book grade 12th in Support and movement chapter. There it is written that " Muscles move eye lid , tongue, beat the heart, popel food through gut, discharge wastes, squeeze out secretion from the glands etc" I just wanted to know whether this is true, if yes then how? BTW this book is not available on any site.
 
Okay. The skunk example I gave is what they are referring to. Which is not a common thing. Glands (endocrine glands ) are not muscle tissue, they are a special kind of tissue derived from the nervous system . Exocrine glands which contribute to digestion also are not generally encased in muscle.

Sometimes the excretions are stored in secondary "containers" or bags that have muscle tissue. Not all glands are like this. Endocrine glands like the thyroid gland or the adrenal glands or the Islets of Langerhans in the pancreas, secrete directly into blood. The pancreas is thought of as an exocrine gland because most of the secretions go into the duodenum - digestive enzymes. But the Islets have a direct connection to the blood - for glucagon and insulin. In both cases for the pancreas, no muscle tissue is there.

Now you see why I was confused. The book in fact gives a somewhat odd take on glands, and I do not think they meant it like that. External to the gland - muscle contractions do move excretions along. Glands are not muscle tissue.
 
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jim mcnamara said:
Okay. The skunk example I gave is what they are referring to. Which is not a common thing. Glands (endocrine glands ) are not muscle tissue, they are a special kind of tissue derived from the nervous system or contribute to digestion. Exocrine glands also are not generally encased in muscle.

Sometimes the excretions are stored in secondary "containers" or bags that have muscle tissue. Not all glands are like this. Endocrine glands like the thyroid gland or the adrenal glands or the Islets of Langerhans in the pancreas, secrete directly into blood. The pancreas is thought of as an exocrine gland because most of the secretions go into the duodenum - digestive enzymes. But the Islets have a direct connection to the blood - for glucagon and insulin. In both cases for the pancreas, no muscle tissue is there.

Now you see why I was confused. The book in fact gives a somewhat odd take on glands, and I do not think they meant it like that. External to the gland - muscle contractions do move excretions along. Glands are not muscle tissue.
They might refer to lymphatic system. Because any secretion from cells does not happen directly to blood but it first secreted into tissue fluid and then into lymph vessels whose walls are muscular. These lymph vessels return the tissue fluid back to blood vessels along with secretion. Is that right?
 
Yes. In any case the statement in the book will cause confusion.
 
jim mcnamara said:
Yes. In any case the statement in the book will cause confusion.
Yeah but I have to admit this as it is in my book. But there is not much detail of endocrine glands on any site that how they secrete hormones and what is the anatomy of these glands. Thank you for your help
 
Aafia said:
I have read it in my biology book grade 12th in Support and movement chapter. There it is written that " Muscles move eye lid , tongue, beat the heart, popel food through gut, discharge wastes, squeeze out secretion from the glands etc" I just wanted to know whether this is true, if yes then how? BTW this book is not available on any site.

Did you mean sphincter muscles?
 
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  • #10
Fervent Freyja said:
Did you mean sphincter muscles?
No this mentions about all types of muscles. Is there any sphincter in glands ?
 
  • #11
No. Some of the mechanisms you have asked about are caused by sphincter muscles, not glands...
 
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