Pituitary dwarfism is caused by problems arising from the pituitary gland. The pituitary gland, also called the hypophysis, is a gland at the base of the brain that produces many different hormones. This gland is divided into the anterior (front) and posterior (back) halves. The anterior pituitary produces six hormones: growth hormone, adrenocorticotropin (corticotropin), thyroid stimulating hormone (thyrotropin), prolactin, follicle stimulating hormone, and lutenizing hormone. The posterior pituitary gland only produces two hormones: antidiuretic hormone (vasopressin) and oxytocin.
The growth process begins in the lower part of the forebrain in a small organ called the hypothalamus. The hypothalamus releases hormones that regulate the production of other hormones. When the hypothalamus releases growth hormone-releasing hormone (GHRH), the anterior pituitary is stimulated to release growth hormone (GH). Growth hormone then acts on the liver and other tissues and stimulates them to secrete insulin-like growth factor-1 (IGF-1). IGF-1 directly promotes the development of bone and muscle, causing bones to grow in length, and muscles to increase protein synthesis (make more protein).
Since growth is a complex phenomenon, it may be slowed down or stopped by abnormalities arising at any point in the process. Thus, dwarfism can result if there is a deficiency in any of these hormones, if there is a failure in the receptor cells receiving the hormonal stimuli, or if the target cells are unable to respond.
At its most basic, pituitary dwarfism results from decreased production of hormones by the anterior pituitary. When none of the hormones of the anterior pituitary are adequately produced, this is called panhypopituitarism. A common form of pituitary dwarfism is due to deficiencies in the production of growth hormone (GH). When less GH than normal is produced during childhood, an individual's arms, legs, and other structures continue to develop in normal proportions, but at a decreased rate.
<span>
hopre i helped</span>
<em>Hardness is a measure of how resistant solid matter is to various kinds of permanent shape change when a force is applied</em> <em>Macroscopic hardness is generally characterized by</em> <em>strong intermolecular bonds</em>, <em>but the behavior of solid materials under force is complex; therefore,</em> <em>there are different measurements of hardness</em>: <em>scratch hardness, indentation hardness, and rebound hardness. Hardness is dependent on ductility, elastic stiffness, plasticity, strain, strength, toughness, viscoelasticity, and viscosity. Common examples of hard matter are ceramics, concrete, certain metals, and super hard materials, which can be contrasted with soft matter.</em>
Answer:
A device to measure the dimensions of a object
Explanation:
Answer:
Abiotic
Explanation:
They aren't a living organism so it's abiotic I assume.
Answer:
transportation
Explanation:
looking at nighttime satellite photos that show dark landscapes illuminated by glowing urban dots. On the surface, these seem like clear evidence of city dwellers' oversized energy footprints.
And when comparing big cities and small towns directly, a Philadelphia, Pennsylvania, obviously dwarfs the power consumption of a Philadelphia, Tennessee Urban and rural populations use energy differently, though, which complicates such broad comparisons.
Despite hosting regular traffic jams, cities win the head-to-head efficiency matchup in transportation thanks to their mass transit systems and denser layouts, which promote walking and bicycling. Small-town and suburban residents usually have to drive themselves to get around, which isn't cheap.
According to EIA data, urban U.S. households own an average of 1.8 vehicles each, compared with 2.2 for each rural household. Urban families also drive about 7,000 fewer miles annually than their rural counterparts, saving more than 400 gallons of gasoline and roughly $1,300-$1,400 at current gas prices.
( I hoped this helped! :D )
