KINS 1131: Systems Physiology I Endocrine System Part I: Introduction PDF

KINS 1131: Systems Physiology I Endocrine System Part I: Introduction Lecture Outline: Part I Introduction o Introduction o Endocrinology o Functions of the Endocrine System o Nervous System vs Endocrine System o Control of Secretion o Hormones o Hormones vs Local Chemical Messenge...

KINS 1131: Systems Physiology I Endocrine System Part I: Introduction Lecture Outline: Part I Introduction o Introduction o Endocrinology o Functions of the Endocrine System o Nervous System vs Endocrine System o Control of Secretion o Hormones o Hormones vs Local Chemical Messengers o Receptor Regulation o Chemical Classes o Mechanism of Action o Interactions Endocrinology o Arnold Berthold o First recorded endocrine experiments o Stated: o Endocrine system regulates the internal milieu of an animal o “internal secretions” were liberated by one part of the body and travel via the bloodstream to distant target cells Comb of rooster its because of testestron so comb will shrank if no more testestron Functions of the Endocrine System 1. Help regulate: o Chemical composition and volume of extracellular fluid o Metabolism and energy balance o Contraction of smooth and cardiac muscle fibres o Glandular secretions What is the term for the o Some immune system activities regulation and maintenance of body systems? 2. Control growth and development 3. Regulate operation of reproductive systems Homeostasis 4. Help establish circadian rhythms Flashback: Homeostasis o Ability of the body to maintain constant normal resting internal conditions, even as the outside conditions change. Negative feedback bring our body bck to homeostasis Flashback: Control Systems in the Body o Homeostasis is primarily maintained by 2 control systems: o The nervous system (acts in milliseconds and lasts the same) : very very quickly and not last for a long time start fast end fast o The endocrine system (acts in seconds to hours and lasts seconds to days) : start late long late To bring us back to homestosis through negative feedback mechanism and control body Nervous System vs. Endocrine System o Nervous System o Endocrine System o Fast response o Slow response o Short-term effects o Long-term effects o Uses electrochemical impulses o Uses hormones transported by blood to delivered by neurons to tissue tissue o Turns-on and turns-off endocrine system functions o Makes adjustments to maintain homeostasis by overriding endocrine controls Control of Hormone Release o What triggers hormone release in the first place? 1. Humoral Stimulus o Hormones released in response to changing blood levels of certain ions and nutrients o Simplest endocrine controls o e.g., parathyroid gland monitors blood calcium levels → secretion of parathyroid hormone by parathyroid glands → increased blood calcium levels Control of Hormone Release 2. Neural Stimuli o Nerve fibres stimulate hormone release o e.g., sympathetic nervous system stimulation of adrenal medulla → epinephrine Cortex of adrenal gland Control of Hormone Release 3. Hormonal Stimuli o Hormones released in response to other hormones o e.g., anterior pituitary hormones regulated by releasing and inhibiting hormones of the hypothalamus → other hormones released Lecture Outline: Part I Introduction o Introduction o Endocrinology o Functions of the Endocrine System o Nervous System vs Endocrine System o Control of Secretion o Hormones o Hormones vs Local Chemical Messengers o Receptor Regulation o Chemical Classes o Transport & Mechanism of Action o Interactions Hormones vs Local Chemical Messengers o Hormones o Act on distant target Distante Target cells not the close one chemical o Local Chemical Messengers o Autocrines o Chemicals that exert effects on the same cells that secrete them o Paracrines o Locally acting chemicals that affect cells other than those that secrete them Receptor Regulation o Target cell specificity o Target cell activation depends on: 1. Blood levels of the hormones 2. Relative number of receptors on or in the target cell 3. Affinity of binding between receptor and hormone Hormones just can effect on their specific reseptor **** So if u have a lot of specific hormones in ur body but u do not have enough receptor u are not getting a very big response **** Hormones need receptor to it has to bind with receptor Receptor Regulation o Hormones can influence the number of their receptors Would up-regulation o Up-regulation increase or decrease o Decreased/deficient blood hormone levels → target cells form more sensitivity to a hormone? receptors in response o Down-regulation o Rising/prolonged hormone levels → desensitization of target cells and loss of receptors Would down-regulation increase or decrease hormone effects? o Concentration of hormones reflects We do not have enough hormon o Its rate of release receptor so decrease an effect o Speed it is inactivated and removed from the body o Degraded by enzymes in target cells o Removed from blood by the kidneys or liver and excreted 1.How fast release 2.how fast down Hormones: Chemical Classes Lipid-Soluble Water-Soluble 1. Steroid hormones 1. Amine hormones o Derived from cholesterol o Synthesized by removing a molecule of CO2 and modifying certain amino acids while 2. Thyroid hormones (T3 and T4) retaining an amino group o Synthesized by attaching iodine to the amino o e.g. Catecholamines and histamine acid tyrosine 2. Peptide & Protein hormones 3. Nitric Oxide o These are amino acid polymers o Hormone and neurotransmitter 3. Eicosanoid hormones o Derived from a 20-carbon fatty acid o Prostaglandins & leukotrienes Hormones: Chemical Classes Chemical Class Hormones Site of Secretion LIPID SOLUBLE Steroid Hormones Aldosterone, cortisol, androgens Adrenal cortex Testosterone Testes Estrogens, progesterone Ovaries Thyroid Hormones T3 and T4 Thyroid gland Nitric Oxide Gas Nitric Oxide Endothelial cells in blood vessels WATER SOLUBLE Amines Catecholamines (epinephrine, norepinephrine) Adrenal medulla Melatonin Pineal gland Histamine Mast cells in connective tissue Serotonin Platelets in blood Peptides and All hypothalamic releasing and inhibiting hormones Hypothalamus proteins Oxytocin, antidiuretic hormone Posterior pituitary Growth hormone, thyroid-stimulating hormone, adrenocorticotropic Anterior pituitary hormone, follicle-stimulating hormone, luteinizing hormone, prolactin Insulin, glucagon Pancreas Parathyroid hormone Parathyroid glands Calcitonin Thyroid gland Erythropoietin Kidneys Leptin Adipose tissue Lecture Outline: Part I Introduction o Introduction o Endocrinology o Functions of the Endocrine System o Nervous System vs Endocrine System o Control of Secretion o Hormones o Hormones vs Local Chemical Messengers o Receptor Regulation o Chemical Classes o Transport & Mechanism of Action o Interactions Hormones: Transport & Mechanism of Action o Hormones circulate in the blood in two forms o Free o Bound to transport protein Which lipid-soluble hormones, free or o Lipid-soluble NOT bound referred to as “free fraction” bound, exert effects? o Free fraction diffuses from bloodstream to bind to receptor o Transport protein functions: 1. Lipid-soluble temporarily water-soluble Most of blood is water :plasma 2. Slow rate of loss via excretion by limiting passage of small hormones filtration in kidneys 3. Provide ready reserve of hormone to blood stream Hormones: Transport & Mechanism of Action o Hormone action on target cells 1. Alter plasma membrane permeability of membrane potential by opening or closing ion channels 2. Stimulate synthesis of proteins or regulatory molecules 3. Activate or deactivate enzyme systems 4. Induce secretory activity 5. Stimulate mitosis Hormones: Transport & Mechanism of Action o Video Hormones: Transport & Mechanism of Action o Lipid-soluble hormones (steroid and thyroid hormones) o Can enter target cell o Act on intracellular receptors and directly activate genes Hormones: Transport & Mechanism of Action o Water-soluble hormones (amino acid, peptide & protein, and eicosanoids) o Cannot enter target cells o Act on plasma membrane receptors o Use secondary messenger systems o Couple with G proteins to exert effects inside the cell o Example: cyclic AMP (cAMP) Why can’t water-soluble hormones enter cells directly? Hormones: Transport & Mechanism of Action o Video Hormones & Target Cells: Interactions o Hormone interactions 1. Permissiveness o One hormone cannot exert its full effects without another hormone being present o e.g., thyroid hormone needed for development of reproductive system 2. Synergism o More than one hormone produces the same effects on a target cell o e.g., glucagon and epinephrine acting together → more glucose being released by the liver into the blood 3. Antagonism o One or more hormones oppose the actions of another hormone o Antagonists may compete for same receptor, act through different pathways or cause down-regulation for the other hormone o e.g., insulin lowers blood glucose levels but opposed by glucagon Lecture Outline: Part I Introduction o Introduction o Endocrinology o Functions of the Endocrine System o Nervous System vs Endocrine System o Control of Secretion o Hormones o Hormones vs Local Chemical Messengers o Receptor Regulation o Chemical Classes o Mechanism of Action o Interactions KINS 1131: Systems Physiology I Endocrine System Part II: Hypothalamus & Pituitary Lecture Outline: Part II o Hypothalamus o Pituitary o Pituitary Gland Structure & Function o Anterior Pituitary Hormones o Growth hormone (GH); aka: somatotropin o Thyroid stimulating hormone (TSH) o Adrenocorticotropic hormone (ACTH) o Follicle stimulating hormone (FSH) o Luteinizing hormone (LH) o Prolactin o Posterior Pituitary & Hypothalamic Hormones o Oxytocin o Antidiuretic Hormone (ADH) Major Endocrine Organs Need to know: The gland (name, location, identification) The structure (anatomy) Hormone(s) released Stimulus for release General hormone effect Hypothalamus o Hypothalamus o Receives input from external and internal environment (sensory nervous system) o Subject to stimuli from ‘higher centres’ o Controls the autonomic nervous system o Acts with limbic system to regulate o Emotional and behavioural patterns o Eating and drinking o Body temperature o Sleep/wake cycle o Pituitary gland secretions o Interaction of hypothalamus and pituitary links nervous and endocrine systems o Nervous system regulates the endocrine system → endocrine activity adjusts the activity of the CNS Hypothalamus Hypothalamus o Hypothalamus synthesizes & releases > 9 different hormones: o Thyrotropin-releasing hormone (TRH) o Corticotropin-releasing hormone (CRH) o Growth hormone-releasing hormone (GHRH) o Prolactin releasing hormone (PRH) o Aka Prolactin releasing factor o Gonadotropin-releasing hormone (GnRH) o Most hormones released by the hypothalamus act on the pituitary gland. Lecture Outline: Part II o Hypothalamus o Pituitary o Pituitary Gland Structure & Function o Anterior Pituitary Hormones o Growth hormone (GH); aka: somatotropin o Thyroid stimulating hormone (TSH) o Adrenocorticotropic hormone (ACTH) o Follicle stimulating hormone (FSH) o Luteinizing hormone (LH) o Prolactin o Posterior Pituitary & Hypothalamic Hormones o Oxytocin o Antidiuretic Hormone (ADH) Pituitary Gland Structure & Function o Pituitary gland aka hypophysis (“to grow under”) o Location: o Sella turcica of sphenoid bone Pituitary Gland Structure & Function o Pea-shaped o Two lobes o Anterior pituitary o Posterior pituitary Anterior pituitary Infundibulum Posterior pituitary Anterior Pituitary Gland o Anterior Pituitary (adenohypophysis) o Glandular tissue o Link to hypothalamus o Capillary system (i.e., no direct neural link) o Manufactures and secretes many hormones: o Growth hormone (GH) o Thyroid stimulating hormone (TSH) o Adrenocorticotropic hormone (ACTH) o Follicle stimulating hormone (FSH) o Luteinizing hormone (LH) o Prolactin Anterior Pituitary Hormones Growth Hormone Released Anterior Pituitary from Target Cell(s) Main Effect(s) Cell growth and tissue repair Protein synthesis, formation of collagen, bone deposit Mobilizes fats (lipolysis), spares glucose Anterior Pituitary Hormones Thyroid Stimulating Hormone Released Anterior Pituitary from Target Cell(s) Main Effect(s) Stimulates synthesis and secretion of thyroid hormones Anterior Pituitary Hormones Adrenocorticotropic Hormone (ACTH) Released Anterior Pituitary from Target Cell(s) Main Effect(s) Stimulates release of corticosteroids (e.g., cortisol) Anterior Pituitary Hormones Follicle Stimulating Hormone (FSH) Released Anterior Pituitary from Target Cell(s) Main Effect(s) Males: Sperm production Females: Egg production and secretion of estrogen Anterior Pituitary Hormones Luteinizing Hormone (LH) Released Anterior Pituitary from Target Cell(s) Main Effect(s) Males: Stimulates testosterone production Females: Stimulates secretion of estrogen and progesterone Triggers ovulation Anterior Pituitary Hormones Prolactin Released Anterior Pituitary from Target Cell(s) Main Effect(s) Females: Stimulates milk production and secretion Males: Unclear but low levels associated with sexual disfunction, and high levels associated with decreased testosterone production Lecture Outline: Part II o Hypothalamus o Pituitary o Pituitary Gland Structure & Function o Anterior Pituitary Hormones o Growth hormone (GH); aka: somatotropin o Thyroid stimulating hormone (TSH) o Adrenocorticotropic hormone (ACTH) o Follicle stimulating hormone (FSH) o Luteinizing hormone (LH) o Prolactin o Posterior Pituitary & Hypothalamic Hormones o Oxytocin o Antidiuretic Hormone (ADH) Posterior Pituitary Gland o Posterior Pituitary o Neural tissue (axons of hypothalamic neurons) o Link to hypothalamus o Axonal connections called hypothalamic- hypophyseal tract/axis (aka hypo-hypo axis) o Stores neurohormones secreted from hypothalamus (not a true endocrine gland): o Oxytocin o Antidiuretic hormone (ADH) Posterior Pituitary Hormones o Oxytocin in females during childbirth: o Stimulates uterine smooth muscle contraction o Released during labour and childbirth o *drug used to induce labour o As the uterus is stretched… o Impulses sent to hypothalamus o More oxytocin produced o More powerful contractions o *positive feedback loop Posterior Pituitary Hormones o Oxytocin in females who are nursing o Oxytocin stimulates milk secretion in response to stimulation of the areolas and nipples What anterior pituitary hormone was also involved in milk secretion? Posterior Pituitary Hormones o Oxytocin in males and non-pregnant females o Bonding hormone o Released during sexual arousal and orgasm o Role in pleasure/satisfaction o Released during affectionate and trusting behaviors o Promotes nurturing and affectionate behaviour aka “cuddle hormone” o “moral molecule”? o https://www.ted.com/talks/paul_zak_trust_morality_and_oxytocin Posterior Pituitary Hormones Oxytocin Released Posterior Pituitary from Where is this hormone synthesized? Target Cell(s) Main Effect(s) Females: Childbirth: uterine contractions Nursing: milk secretion Males & Non-pregnant Females: Promotes bonding and caregiving, sexual pleasure/satisfaction Posterior Pituitary Hormones o Antidiuretic Hormone (aka vasopressin) o Inhibits urine formation (diuresis) and helps to prevent dehydration Dehydration Inadequate fluid intake Excessive sweating (exercise) Increased blood solute concentration Low blood pressure Detected by hypothalamic osmoreceptors Adequate or excessive water intake Decreased blood solute concentration Alcohol Detected by hypothalamic osmoreceptors Release of ADH ADH release inhibited Kidneys reabsorb water to blood stream Water not reabsorbed → Produce less urine to blood stream → Produce more urine Posterior Pituitary Hormones o Antidiuretic Hormone o In high blood concentrations: o Vasoconstriction (visceral blood vessels) o Response to severe blood loss (and therefore sharp decrease in blood pressure) → increase in ADH → vasoconstriction → increased blood pressure Posterior Pituitary Hormones Antidiuretic Hormone (ADH) Released Posterior Pituitary from Where is this hormone synthesized? Target Cell(s) Blood vessels Main Effect(s) Inhibits urine formation In high concentrations can cause vasoconstriction Lecture Outline: Part II o Hypothalamus o Pituitary o Pituitary Gland Structure & Function o Pituitary-Hypothalamic Relationships o Anterior Pituitary Hormones o Growth hormone (GH); aka: somatotropin o Thyroid stimulating hormone (TSH) o Adrenocorticotropic hormone (ACTH) o Follicle stimulating hormone (FSH) o Luteinizing hormone (LH) o Prolactin o Posterior Pituitary & Hypothalamic Hormones o Oxytocin o Antidiuretic Hormone (ADH) KINS 1131: Systems Physiology I Endocrine System Part III: Other Endocrine Organs Lecture Outline: Part III o Thyroid Gland o Pancreas o Thyroid Hormones (T3, T4) o Glucagon o Calcitonin o Insulin o Parathyroid Glands o Ovaries & Testes o Parathyroid Hormone o Estrogen & Progesterone o Adrenal Glands o Inhibin o Adrenal Cortex o Relaxin o Aldosterone o Testosterone o Cortisol o Pineal Gland o Adrenal Medulla o Melatonin o Epinephrine/Norepinephrine Thyroid Gland o Located inferior to larynx o Left and right lobes connected by isthmus o Composed of thyroid follicles o T thyrocytes o Produce T3 and T4 o C thyrocytes (parafollicular cells) o Produce calcitonin Video Break: Thyroid Gland Ed.ted.com Thyroid Gland o Thyroid Hormones T3, T4 o Produced by and secreted from T thyrocytes o Affect virtually every cell in the body o Metabolic hormones Thyrotropin-releasing hormone o Increases metabolic rate and body heat production o Regulates tissue growth and development during childhood Thyroid-stimulating hormone o Promotes normal functioning of the heart, nervous, and muscular systems  Thyroid Gland o Calcitonin o Produced and secreted from C thyrocytes (parafollicular cells) o Targets skeleton o Inhibits osteoclast activity and bone resorption Bone o Stimulates calcium uptake into bone matrix sparing o Used as treatment for osteoporosis o Decreases blood calcium levels o Increased blood calcium levels (~20% above normal) → increased calcitonin release → decreased blood calcium levels (to normal range) → decreased calcitonin release o *but, is not primarily involved in blood calcium homeostasis Lecture Outline: Part III o Thyroid Gland o Pancreas o Thyroid Hormones (T3, T4) o Glucagon o Calcitonin o Insulin o Parathyroid Glands o Ovaries & Testes o Parathyroid Hormone o Estrogen & Progesterone o Adrenal Glands o Inhibin o Adrenal Cortex o Relaxin o Aldosterone o Testosterone o Cortisol o Pineal Gland o Adrenal Medulla o Melatonin o Epinephrine/Norepinephrine Parathyroid Gland o Parathyroid Gland o Posterior aspect of thyroid gland o Contains chief cells which secrete parathyroid hormone  Parathyroid Gland: Parathyroid Hormone o Parathyroid Hormone o Most important for blood calcium homeostasis o Increases osteoclast activity Bone o Increases calcium reabsorption sacrificing o Promotes increased absorption of calcium o Increases blood calcium levels Lecture Outline: Part III o Thyroid Gland o Pancreas o Thyroid Hormones (T3, T4) o Glucagon o Calcitonin o Insulin o Parathyroid Glands o Ovaries & Testes o Parathyroid Hormone o Estrogen & Progesterone o Adrenal Glands o Inhibin o Adrenal Cortex o Relaxin o Aldosterone o Testosterone o Cortisol o Pineal Gland o Adrenal Medulla o Melatonin o Epinephrine/Norepinephrine Adrenal Glands o Adrenal Glands (aka suprarenal glands) o Superior to kidneys o Two glands o Adrenal Cortex o Adrenal Medulla Adrenal Glands o Adrenal Glands (aka suprarenal glands) o Adrenal Cortex o Corticosteroids o Mineralocorticoids o Aldosterone o Glucocorticoids Adrenal Cortex o Cortisol o Gonadocorticoids Adrenal Medulla o Androgens o Adrenal Medulla o Catecholamines adrenal gland o Epinephrine o Norepinephrine  Adrenal Cortex Adrenal Cortex Adrenal Medulla o Mineralocorticoid: Aldosterone o Regulate electrolyte (mineral salt) concentrations in extracellular fluids o Stimulates Na+ reabsorption and water retention in kidneys o Na+ concentration changes → movement of water → blood volume changes → blood pressure Typical Stimulus Extenuating Circumstances Renin-angiotensin-aldosterone mechanism  Adrenal Cortex Adrenal Cortex Adrenal Medulla o Glucocorticoids: Cortisol o Mobilization of fuels o Formation of glucose from fats and proteins o Increases vasoconstriction → increased blood pressure → quick distribution of nutrients Corticotropin-releasing hormone o Suppresses the immune system and inhibits inflammatory response by decreasing function of WBCs Adrenocorticotropic hormone o Long-term/excessive effects o Affects collagen production → weakens connective tissue lipolysis  Adrenal Cortex Adrenal Cortex: Gonadocorticoids Adrenal Medulla o Gonadocorticoids: Androgens o Male sex hormones o Converted to testosterone in males and estrogen in females o In adult women o Thought to be responsible for sex drive and estrogen production post-menopause  Adrenal Cortex Adrenal Medulla Adrenal Medulla o Catecholamines: Epinephrine & Norepinephrine o Stimulated by sympathetic nervous system o Intensify effects of sympathetic nervous system o Increases heart rate and blood pressure o Breaks down glycogen to glucose o Increases metabolism Adrenal Gland and Stress What would be the effect of chronic stress on blood pressure? What’s the effect of chronic stress on the immune system? Lecture Outline: Part III o Thyroid Gland o Pancreas o Thyroid Hormones (T3, T4) o Glucagon o Calcitonin o Insulin o Parathyroid Glands o Ovaries & Testes o Parathyroid Hormone o Estrogen & Progesterone o Adrenal Glands o Inhibin o Adrenal Cortex o Relaxin o Aldosterone o Testosterone o Cortisol o Pineal Gland o Adrenal Medulla o Melatonin o Epinephrine/Norepinephrine Pancreas o Pancreas o Contains both endocrine and exocrine gland cells o Exocrine: excreting digestive enzymes via ducts to the intestine o Endocrine: secretion of insulin and glucagon o Pancreatic islets (aka islets of Langerhans) o Alpha cells o Synthesize glucagon o Beta cells o Produce insulin Video Break: Pancreas Ed.ted.com Pancreas: Glucagon & Insulin o Glucagon o Hyperglycemic hormone o Increases blood glucose levels o Breaks down glycogen into glucose and releases glucose from liver cells to blood stream o Insulin o Hypoglycemic hormone o Lowers blood glucose levels o Enhancing membrane transport of glucose into muscle and fat cells (and therefore out of blood stream) o Inhibits breakdown of glycogen to glucose Pancreas: Glucagon & Insulin beta cells Stimuli → change in blood glucose levels alpha cells Lecture Outline: Part III o Thyroid Gland o Pancreas o Thyroid Hormones (T3, T4) o Glucagon o Calcitonin o Insulin o Parathyroid Glands o Ovaries & Testes o Parathyroid Hormone o Estrogen & Progesterone o Adrenal Glands o Inhibin o Adrenal Cortex o Relaxin o Aldosterone o Testosterone o Cortisol o Pineal Gland o Adrenal Medulla o Melatonin o Epinephrine/Norepinephrine Ovaries o Ovaries produce: 1. Estrogen and Progesterone o Promote development of female sex characteristics during puberty (eg: widening of hips, enlargement of breasts) o Prepare the uterine lining for implantation and the mammary glands for lactation 2. Inhibin o Inhibits release of FSH 3. Relaxin (along with placenta) during pregnancy o Increases extensibility of connective tissue o What purpose does this serve? o What implications would this have for pregnant women with respect to injury during pregnancy? Testes o Testes produce: 1. Testosterone o Promotes development of male sex characteristics during puberty (eg: voice changes, facial hair) o Stimulates descent of testes before birth o Regulates sperm production 2. Inhibin o Inhibits release of FSH Lecture Outline: Part III o Thyroid Gland o Pancreas o Thyroid Hormones (T3, T4) o Glucagon o Calcitonin o Insulin o Parathyroid Glands o Ovaries & Testes o Parathyroid Hormone o Estrogen & Progesterone o Adrenal Glands o Inhibin o Adrenal Cortex o Relaxin o Aldosterone o Testosterone o Cortisol o Pineal Gland o Adrenal Medulla o Melatonin o Epinephrine/Norepinephrine Pineal gland o Melatonin is a hormone produced by the pineal gland o Believed to be involved in “circadian rhythms” (setting the “biological clock”) by promoting sleepiness o SADD seasonal affective disorder depression: thought to be due (partly) to overproduction of melatonin Lecture Outline: Part III o Thyroid Gland o Pancreas o Thyroid Hormones (T3, T4) o Glucagon o Calcitonin o Insulin o Parathyroid Glands o Ovaries & Testes o Parathyroid Hormone o Estrogen & Progesterone o Adrenal Glands o Inhibin o Adrenal Cortex o Relaxin o Aldosterone o Testosterone o Cortisol o Pineal Gland o Adrenal Medulla o Melatonin o Epinephrine/Norepinephrine Lecture Outline: Part IV Sleep, Hormones & Health Watch the video (posted separately) and answer the following: Sleep and Hormones: 1. How does sleep impact testosterone levels in men? Amount of Sleep: 2. How does sleep impact melatonin production and 1. What percentage of the population can function on less release? than 7 hours of sleep a night without any impairment? 0 2. What range is enough sleep for most adults? 8 :7-9 Stages of Sleep and Function: Sleep and Weight: 1. Which stage of sleep, REM or deep non-REM sleep is 1. What is the role of sleep and weight gain? associated with problem solving? 2. Where is leptin produced and what does it do? a. How does this stage of sleep go about solving problems? 3. What does Ghrelin do? Sleep and the Brain: Factors Impacting Sleep: 1. Why is sleep needed before and after learning? 1. What is the impact of light on sleep? a. What brain structure is affected by sleep in the above question? hypocampuss 2. What is the impact of stress on sleep? 3. What is the effect of caffeine on sleep? 2. What impact does sleep have on emotional regulation? 4. What is the effect of alcohol on sleep? a. What brain structures are affected by sleep with regard to emotional regulation? 5. What is the function of “regularity” on sleep? a. What is “social jetlag”? 3. What is the glymphatic system, how does it relate to Alzheimer’s, and what is the role of sleep? 6. What is a chronotype?