Epinephrine, or adrenaline, is regulated by the nervous system when an environmental stress occurs. Nerve signals travel through the spinal cord to the adrenal medulla, which secretes epinephrine and norepinephrine. Release of epinephrine is not caused by a tropic hormone or other cell signal, but by direct neural stimulation.

Release of epinephrine is a short-term stress response that increases blood pressure, breathing rate, glycogen break down to glucose, and metabolic rate. This increases alertness, and decreases digestive, excretory and reproductive system activity. Epinephrine is essentially responsible for the effects of the sympathetic nervous system, which is active during the "fight or flight" response.

Following a large uptake of glucose, the body will begin to release insulin to facilitate storage of the glucose molecules within the cells of the liver, as well as skeletal muscles.

Glucagon is released when blood glucose levels are low and promotes an increase in free blood glucose. The breakdown of glycogen into free blood glucose is a process known as glycogenolysis; this process is stimulated by glucagon and inhibited by insulin. Gluconeogenesis is the generation of glucose from non-carbohydrate carbon substrates; it is also stimulated by glucagon and inhibited by insulin.

Endocrine glands release hormones directly into the circulatory system, where they can act on target effector organs. The kidneys serve both endocrine and exocrine functions. Releasing urine filtrate through ducts is an exocrine function. Kidneys also release the hormone erythropoietin, which promotes the generation of new red blood cells.

The hormone described in the question is luteinizing hormone (LH). If fertilization occurs, the LH levels will decrease and human chorionic gonadotropin (hCG) is released from the placenta to simulate LH function.

Calcitonin is the hormone in charge of taking calcium ions from the bloodstream and incorporating them into the matrix of the bone. This allows the bone to produce hydroxyapatite crystals from the calcium, which can strengthen the matrix of the bone and reduce the effect of osteoporosis. Parathyroid hormone and calcitriol (vitamin D) have opposite effects as calcitonin - they increase the blood calcium levels through breaking down bone and increasing the absorption of calcium in the gut. Growth hormone is responsible for normal growth and development of the body, especially bones and skeletal muscles. It is not involved in regulation of minerals such as calcium. Calmodulin is a calcium binding protein that regulates many intracellular processes. 

The hormone responsible for the reduction of calcium in the blood is calcitonin. This hormone promotes the assimilation of calcium ions into the bone matrix from the blood. This reduces the concentration of calcium ions in the blood and increases the concentration found in the bone. Meanwhile, PTH has the opposite effect by taking calcium ions from the bone matrix and releasing them into the blood.

The correct answer is oxytocin because this hormone is produced in the posterior pituitary gland along with antidiuretic hormone (ADH). Oxytocin is responsible for uterine contraction during labor in a positive feedback look mechanism.

Melatonin is produced in the pineal gland which is a gland in the brain responsible for the body’s circadian rhythms and sleep/wake cycle. The concentration of melatonin peaks at night and causes us to fall asleep. Melatonin is degraded while we sleep so that when we wake up in the morning we start to produce it again throughout the day.

Because insulin receptors have been desensitized to insulin, the addition of more insulin will not have any effect. This is why Type II Diabetes is much more difficult to treat than Type I. The recommended course of action for individuals with Type II diabetes is to eat healthy and exercise.

The adrenal gland is almost certainly responsible for your reaction, as this gland contains the adrenal medulla, which is capable of releasing epinephrine. During stressful situations, the sympathetic nervous system triggers the fight-or-flight response. During this response, sympathetic nerves stimulate the adrenal medulla, which then releases epinephrine. Epinephrine raises blood sugar levels and increases blood pressure, brain oxygen consumption, and heart rate. It prepares an individual to either fight a threat (such as a dog), or run away from it.

The anterior pituitary is capable of releasing a number of hormones including growth hormone, thyroid-stimulating hormone, and prolactin.

The pineal gland is involved in biorhythms and sleep patterns. 

The adrenal cortex is stimulated by adrenocorticotropic hormone and releases corticosteroids in response to long-term stress, such as sleep or food deprivation.