Definition of hormone
Any substance produced by one tissue and conveyed by the bloodstream to another to effect physiological activity.
Examples of hormone in the following topics:
- These contractions are believed to be triggered by high concentrations of the hormone ghrelin.
- This theory developed from the findings that bilateral lesions of the lateral hypothalamus can cause anorexia, a severely diminished appetite for food, while bilateral lesions on the ventromedial hypothalamus can cause overeating and obesity.Leptin, a hormone secreted exclusively by adipose cells in response to an increase in body fat mass, is an important component in the regulation of long-term hunger and food intake.
- Ghrelin, a hormone produced by the stomach, triggers the release of orexin from the hypothalamus, thus signalling to the body that it is hungry.StarvationStarvation is a severe deficiency in caloric energy, nutrient, and vitamin intake.
- Hunger is divided into long-term and short-term regulation, each stimulating different hormone responses from the hypothalamus.
- Sustained or chronic stress, in particular, leads to elevated hormones such as cortisol, the "stress hormone," and reduced serotonin and other neurotransmitters in the brain, including dopamine, which has been linked to depression.
- Cortisol, also known as the “stress hormone”, plays an integral role in our body's reaction to stress.
- The hypothalamic-pituitary-adrenocortical system reacts within a person's brain, and it releases the hormone cortisol from the adrenal glad when one is exposed to a stressor.
- The best way to describe hormones is to think of a lock and a key - only a certain hormone can create a certain response within your body.
- This gland regulates all seven of the other glands, and secretes growth hormone .
- These rhythms can influence sleep-wake cycles, hormone release, body temperature and other important bodily functions.
- The body’s master clock, or the suprachiasmatic nucleus (abbreviated SCN), controls the production of melatonin, a hormone that makes you sleepy.The SCN is a small group of brain cells located in the hypothalamus that controls the circadian cycles and influences many physiological and behavioral rhythms occurring over a 24-hour period, including the sleep/wake cycle.
- Stressful stimuli cause the hypothalamus to signal the adrenal medulla (which mediates short-term stress responses) via nerve impulses, and the adrenal cortex (which mediates long-term stress responses) via the hormone adrenocorticotropic hormone (ACTH), which is produced by the anterior pituitary .
- Oxytocin, also known as the “hormone of love,” is released in both men and women during sexual intercourse when an orgasm is achieved.
- Follicle-stimulating hormone (FHS) is responsible for ovulation in women by triggering egg maturity; it also stimulates sperm production in men.
- Luteinizing hormone (LH) triggers the release of a mature egg in women during the process of ovulation.In males, testosterone appears to be a major contributing factor to sexual motivation.
- Studies in mice and human cancer cells grown in a laboratory have found that the stress hormone norepinephrine, part of the body’s fight-or-flight response system, may promote angiogenesis and metastasis.
- Hormones play an organizational role, priming the body to behave in a certain way once puberty begins, and an activational role, triggering certain behavioral and physical changes.Puberty occurs through a long process, and begins with a surge in hormone production, which in turn causes a number of physical changes.
- Other causes may include aging, fatigue, hormone imbalance, pregnancy, postpartum depression, medications (such as SSRIs), or psychiatric conditions, such as depression and anxiety.Sexual arousal disorders were previously known as frigidity in women and impotence in men, though these have now been replaced with less judgmental terms, such as erectile dysfunction.
- Biological factors that may influence gender identity include pre- and post-natal hormone levels and genetic makeup.