Video Transcript
Which of the following tables
correctly summarizes the hormones released from each part of the pituitary
gland? (A) The anterior part releases
growth hormone and gonadotropic hormones, while the posterior releases ADH and
oxytocin. (B) The anterior part releases ADH
and oxytocin, while the posterior releases growth hormone and gonadotropic
hormones. (C) The anterior part releases ADH
and growth hormone, while the posterior releases oxytocin and gonadotropic
hormones. Or (D) the anterior part releases
gonadotropic hormones and oxytocin, while the posterior releases growth hormone and
ADH.
This question asks us about the
pituitary gland, which is a small endocrine gland, about the size of a pea, located
at the base of the brain. Despite its small size, the
pituitary gland is responsible for regulating many important biological processes,
including metabolism, growth, and reproduction. It does this by releasing many
different chemical messengers called hormones.
The pituitary gland is often
referred to as the master gland in the human body. This is because the hormones it
secretes can influence nearly every organ and tissue, even other endocrine
glands.
This important gland is divided
into two main lobes: the anterior lobe, which is located closer to the front of the
brain, and the posterior lobe, which is located closer to the back of the brain. These two lobes are responsible for
secreting different hormones. In order to answer our question
correctly, we need to review four of the hormones that can be released by the
pituitary gland and identify which lobe, anterior or posterior, releases them.
Let’s start with the posterior lobe
of the pituitary gland. The posterior lobe acts more like a
storage place for the hormones produced in the hypothalamus, the brain structure
that is located just above the pituitary gland. One such hormone that is stored in
the posterior pituitary gland before being secreted into the bloodstream is
oxytocin. Oxytocin is responsible for
stimulating uterine contractions during childbirth in biological females.
Another hormone that is secreted
from the posterior pituitary gland is called antidiuretic hormone, which is
sometimes referred to as ADH or vasopressin. ADH acts upon the kidneys,
stimulating them to reabsorb water into the blood.
The anterior lobe of the pituitary
gland both produces and secretes many different hormones, which have a broad range
of effects. These anterior pituitary hormones
include those that are referred to as gonadotropins as they influence other
endocrine glands, the gonads. An example of a gonadotropin is
follicle-stimulating hormone, or FSH, which stimulates the development of an egg
cell in a biological female’s gonads, the ovaries. Interestingly, FSH also plays an
important role in the development of sperm cells in a biological male’s gonads, the
testes.
The final hormone that is listed in
the answer choices is growth hormone, or GH, which is also produced and released
from the anterior pituitary gland. Growth hormone acts on pretty much
all of the body tissues, for example, our muscles and bones, stimulating the growth
of these tissues.
Now that we know which lobe of the
pituitary gland these four different hormones are secreted from, we can answer our
question correctly. The table that correctly summarizes
the hormones released from each part of the pituitary gland is in answer choice
(A). The anterior part releases growth
hormone and gonadotropic hormones, while the posterior releases ADH and
oxytocin.
