Video Transcript
Which of the following best
describes how the hormones produced by the endocrine glands move into the body? (A) Endocrine glands release
hormones into the external environment through a duct. (B) Endocrine glands do not have a
duct and release hormones into the external environment. (C) Endocrine glands do not have a
duct and release hormones directly into the bloodstream. (D) Endocrine glands release
hormones into the bloodstream through a duct.
To answer the question, we need to
recall the unique features of endocrine glands. Endocrine glands are the component
parts that make up the endocrine system. The endocrine glands work like any
other gland found in the body. They are specialized organs that
produce and secrete substances that have different functions. However, unlike many of the other
glands in the body, the endocrine glands do not have tubes or ducts to deliver their
secretions. This is why endocrine glands are
sometimes called ductless glands.
Without ducts or tubes, the cells
of the endocrine glands secrete chemical messengers called hormones directly into
the bloodstream. Once the hormones are in the
bloodstream, they’re carried by the circulatory system to their target organs where
they can exert their effect. So the correct answer choice will
detail the two unique characteristics of an endocrine gland that it is ductless and
releases hormones directly into the bloodstream.
With this information, we’re now
able to answer the question. Endocrine glands do not have a duct
and release hormones directly into the bloodstream.
