1. Given what you have learned so far about the male and female reproductive systems, briefly respond to each of the following questions for each gender: Which hormones are primarily responsible for triggering the onset of puberty? At what age does this typically occur? Describe some of the changes that occur as a result.
Provide answer here
2. Insulin and glucagon are important hormones. Where are they produced, what are the effects of each, and why is the maintenance of homeostasis between these hormones so important?
Provide answer here
3. Choose an endocrine organ from the following list and answer these questions: Where is this organ located? What major hormones does it produce? What are the effects of one or more of the hormones it produces?
· Anterior pituitary gland
· Posterior pituitary gland
· Hypothalamus
· Pineal gland
· Thyroid gland
· Parathyroid glands
· Adrenal glands
_____________________
Male Reproductive System:
Hormones responsible for triggering the onset of puberty: The primary hormone responsible for triggering the onset of puberty in males is testosterone, which is produced by the testes.
Typical age of onset: Puberty in males typically begins between the ages of 9 and 14 years.
Changes that occur: During puberty, males experience several changes, including the growth of testes and penis, development of secondary sexual characteristics like facial hair, deepening of the voice, increased muscle mass, and the onset of sperm production.
Female Reproductive System:
Hormones responsible for triggering the onset of puberty: The primary hormones responsible for triggering the onset of puberty in females are estrogen and progesterone, which are produced by the ovaries.
Typical age of onset: Puberty in females typically begins between the ages of 8 and 13 years.
Changes that occur: As a result of puberty, females experience the development of breasts, growth of pubic and underarm hair, widening of hips, the onset of menstruation, and the ability to conceive and bear children.
Insulin and glucagon:
Insulin: Insulin is produced by the beta cells of the pancreas, specifically in the islets of Langerhans. Its main effect is to lower blood glucose levels by facilitating the uptake of glucose from the bloodstream into cells, particularly in muscle and adipose tissue. Insulin promotes the storage of glucose as glycogen in the liver and muscles, and it also enhances protein synthesis.
Glucagon: Glucagon is also produced by the pancreas, specifically in the alpha cells of the islets of Langerhans. Its main effect is to increase blood glucose levels. Glucagon stimulates the breakdown of glycogen in the liver, releasing glucose into the bloodstream through a process called glycogenolysis. It also promotes gluconeogenesis, the production of glucose from non-carbohydrate sources like amino acids and glycerol.
Importance of homeostasis: Maintaining homeostasis between insulin and glucagon is crucial for regulating blood glucose levels. Insulin helps prevent blood sugar from rising too high, while glucagon prevents it from dropping too low. When blood glucose levels are elevated, insulin is released to promote glucose uptake and storage. Conversely, when blood glucose levels are low, glucagon stimulates the release of stored glucose. The balance between these hormones ensures a stable blood glucose concentration, which is vital for cellular energy production and overall metabolic function.
Endocrine Organ: Thyroid gland
Location: The thyroid gland is located in the neck, just below the Adam’s apple, wrapped around the trachea (windpipe).
Major hormones produced: The thyroid gland produces two primary hormones: thyroxine (T4) and triiodothyronine (T3). These hormones are produced and stored in thyroid follicles.
Effects of the hormones: T4 and T3 are involved in regulating the body’s metabolism. They increase the metabolic rate of cells throughout the body, influencing processes like growth, development, and energy expenditure. These hormones also play a crucial role in the development and functioning of the nervous system, as well as in maintaining body temperature. Additionally, they are involved in regulating heart rate, digestion, and muscle control.
