Billy's Remarkable Voice
Billy is an elderly man who has experienced 'remarkable' vocal changes throughout his life. Long-term growth and development occur as a consequence of hormone secration within the endocrine system. As an individual ages hormone secreation alters, changing how the human body is structured and functions. As a young boy Billy was a falsetto singer in a choir until he endured hormonal changes associated with puberty. He developed a broken tenor which was hard to control as well as his mood. During this period had also developed a larger muscle mass after taking up body building. After he participated in a choir, he engaged in rock and roll and country western singing. The current state his voice is crackly and monotonous. This report will attempt to investigate the hormonal mechanisms underlying the growth and development of Billy's body throughout throughout his life, in particular the mechanisms of the endocrine system.
Organs of the Endocrine System
Figure 1: The diagram above showcases the location of the endocrine organs. The organs of the endocrine system include the hypothalamus, thymus, pancreas, parathyroid glands ovaries, testis, pituitary gland, adrenal glands, pineal gland and thyroid gland. These endocrine organs are responsible for the regulation of reproduction, growth, metabolic rate and energy, fluid and nutrient balance, cardiac output, blood pressure and reproduction (Porterfield, 2001; Finlayson & Sanders, 2007; Marieb & Hoehn, 2014) .
Regulation of Hormone Secretion
Hormones within the endocrine system allow cells to communicate to maintain homoeostasis in the body, a process which continuously aims to create a balanced environment. In the endocrine system, homeostasis occurs through hormone feedback mechanisms. This occurs when hormones to feeback to where it's secreted from to activate or inhibit it's production accordaing to the hormonal blood levels secreted (Porterfield, 2001; Finlayson & Sanders, 2007). Hormone secretion is regulated by three mechanisms of hormone release control; humoral, neural and hormonal (as shown in Table 1 below) (Porterfield, 2001; Finlayson & Sanders, 2007; Marieb & Hoehn, 2014).
Secretion of a hormone is stimulated by changing blood levels of irons and nutrients.
Parathyroid gland is stimulated by low calcium levels in the blood to release the hormone osteoclasts to break down bone and calcium
Secretion of a hormone is stimulated by nerve fibres.
The adrenal medulla is stimulated by the sympathetic nervous system to release norepinephrane and epinephrine in response to stress.
Secreation of a hormone release is dependent on the secretion of another hormone.
Gonadotropin is released from the hypothalamus. It travels through the hyposeal tract into the anterior pituitary lobe. The anterior pituitary lobe is stimulated by gonadotropin to...