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Endocrine and Heart
A & P II
Question | Answer |
---|---|
The PINEAL GLAND is attached to | the roof of the third ventricle of the brain at the midline. |
The PINEAL GLAND produces | MELATONIN, which contributes to setting the body’s biological clock. |
The ADRENAL MEDULLA secretes | EPINEPHRINE and NOREPINEPHRINE, which contribute to the fight-or-flight response. |
When is EPINEPHRINE and NOREPINEPHRINE released | These are released under stress by direct innervation from the ANS. |
The ADRENAL GLANDS are located where | lie atop each kidney and consist of an outer CORTEX (ZONA GLOMERULOSA/FASCICULATA/RETICULARIS) and inner MEDULLA. |
The CORTEX is subdivided into three zones... | The OUTER ZONE secretes hormones classified as MINERALCORTICOIDS, the MIDDLE ZONE secretes hormones classified as GLUCOCORTICOIDS, and the INNER ZONE secretes ANDROGENS. |
The MINERALOCORTICOIDS such as ALDOSTERONE... | increase sodium and water reabsorption, decrease potassium reabsorption, and regulate sodium and potassium levels in the blood. |
The GLUCOCORTICOIDS such as CORTISOL... | promote the metabolism of proteins and triglycerides, and serve as anti-inflammatory agents, and depress the immune response |
The BETA CELLS secrete | INSULIN, which functions to decrease blood levels of glucose and increase tissue utilization of glucose. Levels of glucose in the blood control secretion of insulin. |
The ALPHA CELLS secrete | GLUCAGON, which functions to increase the blood level of glucose. Glucose levels in the blood control its secretion. |
Pancreas Histologically, it is | comprised of patches of cells called the PANCREATIC ISLETS OR ISLET OF LANGERHANS |
The PANCREAS is a | flattened organ posterior and inferior to the stomach. |
THE PANCREAS is both | an exocrine and endocrine organ. |
The PARATHYROIDS are located on | the posterior aspect of the thyroid gland. There is usually a pair on either side. |
The parathyroids secrete | PARATHYROID HORMONE (PTH). |
PARATHYROID HORMONE regulates | the homeostasis of calcium and phosphate by increasing blood calcium levels and decreasing blood phosphate levels, by stimulating osteoclasts. Calcium levels in the blood control the secretion of PTH. |
The THYROID GLAND is located | below to the larynx (voice box) and contains two lobes. |
The thyroid consists of | follicles composed of FOLLICULAR CELLS, which secrete thyroid hormones THYROXINE (T-4) AND TRIIODOTHYRONINE (T-3), and PARAFOLLICULAR CELLS, which secrete CALCITONIN (CT). |
THYROID HORMONES regulate | the basal metabolic rate and oxygen consumption, cellular metabolism, and development. Secretion is mediated through the action of both the hypothalamus and anterior pituitary. |
CALCITONIN (CT) functions to | lower blood levels of calcium and phosphate by depositing mineral salts into bone tissue, via the inhibition of osteoclasts. The level of calcium in the blood controls secretion of |
The POSTERIOR PITUITARY stores two hormones, | OXYTOCIN (OT) and ANTIDIURETIC HORMONE (ADH), which are made in the hypothalamus. |
OXYTOCIN stimulates | the contraction of the uterus and the ejection of milk (“letdown”). |
ANTIDIURETIC HORMONE also called | vasopressin, stimulates water reabsorption by the kidneys. |
The PITUITARY GLAND sits in | the sphenoid bone (sella turcica). It is divided into the ANTERIOR PITUITARY and POSTERIOR PITUITARY. |
The ANTERIOR PITUITARY releases | hormones that regulate a wide range of bodily activities and are activated or inhibited by regulating hormones released by the hypothalamus. |
Seven hormones can be released by the anterior pituitary with proper stimulation from the hypothalamus. These are | human growth hormone (hGH), prolactin (PRL), adrenocorticotropic hormone (ACTH), melanocyte-stimulating hormone (MSH), thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). |
HUMAN GROWTH HORMONE (hGH) stimulates | body growth by acting on skeletal muscles and bone tissue. |
THYROID-STIMULATING HORMONE (TSH) stimulates the | synthesis and secretion of hormones from the thyroid gland and its release is controlled by RH from the hypothalamus. |
FOLLICLE-STIMULATING HORMONE (FSH) functions to | control the development and production of sperm in the male and the development of oocytes in the female. |
LUTEINIZING HORMONE (LH) together with FSH stimulates | ovulation. It also stimulates the secretion of PROGESTERONE and ESTROGENS which prepares the uterus for implantation. |
PROLACTIN (PRL) together with other female hormones initiates | milk secretion from the mammaries. |
ADRENOCORTICOTROPIC HORMONE (ACTH) controls | the production and secretion of glucocorticoids by the adrenal cortex. |
MELANOCYTE-STIMULATING HORMONE (MSH) has | an unknown role in humans, but administration of this hormone will cause darkening of the skin. |
HORMONES are released on demand. The amount of hormone released by a gland is determined by | the body’s need for the hormone at any given time. |
CONTROL OF HORMONE SECRETIONS: | FEEDBACK CONTROL |
Most hormones are released on demand in short bursts, with little or no secretion between bursts. A NEGATIVE FEEDBACK CONTROL MECHANISM prevents | the overproduction or underproduction of a hormone. |
Hormone secretions are controlled by | (1) signals from the nervous system, (2) chemical changes in the blood, and (3) other hormones. |