This document provides an overview of hormones, including:
1. Hormones are chemicals secreted by endocrine glands that travel through the blood and influence other glands and organs. There are two major classes: protein hormones and steroid hormones.
2. The hypothalamus and pituitary gland control hormone release through negative feedback loops. The hypothalamus secretes hormones that stimulate or inhibit the pituitary gland.
3. Hormone disorders can occur if glands do not produce the proper hormones. Examples include congenital adrenal hyperplasia and androgen insensitivity syndrome.
Biochemistry Of Hormones
Contains All Important topics with best key points....
Made By Sanjay kumar (Student Of PharmD Faculty of Pharmacy Hamdard University)
Hormones are chemical messengers that are secreted directly into the blood, which carries them to organs and tissues of the body to exert their functions. There are many types of hormones that act on different aspects of bodily functions and processes.
Growth hormone is secreted by the anterior pituitary gland and promotes body cell growth. It has a half-life of 5-20 minutes in humans. Growth hormone increases protein synthesis and amino acid uptake while decreasing protein breakdown. It also increases fat mobilization from adipose tissue while promoting fat breakdown for energy. Growth hormone stimulates bone and cartilage growth by increasing the production of somatomedins in the liver. Hypoglycemia, decreased fatty acids, and increased amino acids stimulate growth hormone secretion, while hyperglycemia, increased fatty acids, and decreased amino acids decrease its secretion.
Hormones act through receptor-mediated pathways. They bind to receptors on target cells and induce responses. There are several types of hormone receptors, including cell surface receptors like G protein-coupled receptors and tyrosine kinase receptors, as well as intracellular/nuclear receptors found within cells. Hormones are synthesized in various glands and organs throughout the body, then travel through the bloodstream to target tissues to exert their effects, such as regulating metabolism, growth, and development. Hormone receptors trigger intracellular signaling cascades that alter cellular functions. Antagonists can block hormone receptors to inhibit their actions.
Hormones are chemical substances produced in the body that control and regulate the activity of certain cells or organs. They are classified based on their chemical nature as proteins, steroids, or amino acid derivatives. Hormones also bind to either intracellular or cell surface receptors and work through various second messenger systems to stimulate physiological processes. Key functions of hormones include growth, metabolism, reproduction, and mood control. Hormone levels are regulated through feedback mechanisms and various factors can influence their actions.
Hormones are chemical messengers produced by endocrine glands that control various bodily functions like growth, metabolism, and development through negative feedback loops. They travel via bloodstream and have longer-lasting effects than nerve impulses. Examples of glands that produce hormones include the pituitary, thyroid, adrenal, pancreas, ovaries, and testes, with hormones regulating processes such as blood sugar levels, mood, and sexual maturation.
Chemical messengers, Biochemistry of Hormones & their Feedback MechanismZoologist Pakistan
Slides about Chemical Messengers, Hormones, Pheromones, Types of Chemical Messengers, Biochemistry of Chemical Messengers, Feedback Mechanisms of Hormones
The document discusses the mechanisms of action of different types of hormones. Protein and peptide hormones act through cell surface receptors and use secondary messengers like cAMP or calcium to trigger intracellular signaling cascades. Steroid hormones diffuse into cells and act through nuclear receptors to regulate gene expression. The mechanisms allow hormones to control diverse physiological processes like metabolism, development, and reproduction through feedback loops that precisely regulate hormone production and secretion.
Biochemistry Of Hormones
Contains All Important topics with best key points....
Made By Sanjay kumar (Student Of PharmD Faculty of Pharmacy Hamdard University)
Hormones are chemical messengers that are secreted directly into the blood, which carries them to organs and tissues of the body to exert their functions. There are many types of hormones that act on different aspects of bodily functions and processes.
Growth hormone is secreted by the anterior pituitary gland and promotes body cell growth. It has a half-life of 5-20 minutes in humans. Growth hormone increases protein synthesis and amino acid uptake while decreasing protein breakdown. It also increases fat mobilization from adipose tissue while promoting fat breakdown for energy. Growth hormone stimulates bone and cartilage growth by increasing the production of somatomedins in the liver. Hypoglycemia, decreased fatty acids, and increased amino acids stimulate growth hormone secretion, while hyperglycemia, increased fatty acids, and decreased amino acids decrease its secretion.
Hormones act through receptor-mediated pathways. They bind to receptors on target cells and induce responses. There are several types of hormone receptors, including cell surface receptors like G protein-coupled receptors and tyrosine kinase receptors, as well as intracellular/nuclear receptors found within cells. Hormones are synthesized in various glands and organs throughout the body, then travel through the bloodstream to target tissues to exert their effects, such as regulating metabolism, growth, and development. Hormone receptors trigger intracellular signaling cascades that alter cellular functions. Antagonists can block hormone receptors to inhibit their actions.
Hormones are chemical substances produced in the body that control and regulate the activity of certain cells or organs. They are classified based on their chemical nature as proteins, steroids, or amino acid derivatives. Hormones also bind to either intracellular or cell surface receptors and work through various second messenger systems to stimulate physiological processes. Key functions of hormones include growth, metabolism, reproduction, and mood control. Hormone levels are regulated through feedback mechanisms and various factors can influence their actions.
Hormones are chemical messengers produced by endocrine glands that control various bodily functions like growth, metabolism, and development through negative feedback loops. They travel via bloodstream and have longer-lasting effects than nerve impulses. Examples of glands that produce hormones include the pituitary, thyroid, adrenal, pancreas, ovaries, and testes, with hormones regulating processes such as blood sugar levels, mood, and sexual maturation.
Chemical messengers, Biochemistry of Hormones & their Feedback MechanismZoologist Pakistan
Slides about Chemical Messengers, Hormones, Pheromones, Types of Chemical Messengers, Biochemistry of Chemical Messengers, Feedback Mechanisms of Hormones
The document discusses the mechanisms of action of different types of hormones. Protein and peptide hormones act through cell surface receptors and use secondary messengers like cAMP or calcium to trigger intracellular signaling cascades. Steroid hormones diffuse into cells and act through nuclear receptors to regulate gene expression. The mechanisms allow hormones to control diverse physiological processes like metabolism, development, and reproduction through feedback loops that precisely regulate hormone production and secretion.
organic biologically active compounds of different chemical nature that are produced by the endocrine glands, enter directly into blood and accomplish humoral regulation of the metabolism of compounds and functions on the organism level.
Hormones can be classified in several ways based on their chemical composition, mechanism of action, target effects, and whether they stimulate other endocrine glands. The three main types are steroid hormones, peptide hormones, and amine hormones. Steroid hormones are lipophilic and act via nuclear receptors. Peptide hormones are hydrophilic and act through cell surface receptors and secondary messengers like cAMP. Amine hormones have properties of both peptides and steroids. Hormones also differ in their local versus general actions, kinetic versus metabolic effects, and whether they stimulate other glands via tropic hormones or act directly on tissues.
GENERAL MECHANISM OF PEPTIDE AND STEROID HORMONE ACTION.pdfApoorva Rajagopal
Hormones are a type of signaling molecules that are produced by the endocrine glands. They are natural organic substance produced in minute quantity to regulate growth, metabolism and other functions.
Hormones are chemical messengers that are produced in endocrine glands and secreted into the bloodstream to control metabolic and biological activities in target cells. They can be classified based on their chemical nature as amino acid derivatives, proteins/peptides, or steroids, and based on their mechanism of action as group I hormones that bind intracellular receptors or group II hormones that bind cell surface receptors and trigger secondary messengers. Key hormones include reproductive hormones like estrogen and testosterone; thyroid hormones; adrenal hormones like cortisol and aldosterone; calcium regulating hormones calcitriol, PTH, and calcitonin; and others. Abnormalities in hormone levels can lead to diseases and disorders.
The document discusses adrenocortical hormones and their synthesis and secretion. It covers the following key points:
1. The adrenal cortex secretes corticosteroids including mineralocorticoids like aldosterone and glucocorticoids like cortisol.
2. Aldosterone regulates sodium and potassium levels while cortisol regulates glucose levels and has anti-inflammatory effects.
3. Corticosteroid synthesis occurs in the zona glomerulosa, zona fasciulata, and zona reticularis layers of the adrenal cortex from cholesterol.
4. ACTH stimulates cortisol secretion which is regulated by a negative feedback loop with the hypothalamus and
Basic Introduction to the vast science of the endocrine glands and their interactions. A brief review into the physiological processes that result in endocrine disorders.
Hormones are signaling molecules produced by glands that are transported via bloodstream to target distant organs to regulate physiology. They are classified as proteinaceous (peptide) hormones or non-proteinaceous (steroid) hormones. Some important peptide hormones include insulin which regulates carbohydrate and fat metabolism, glucagon which raises blood sugar levels, adrenocorticotropic hormone (ACTH) which regulates glucocorticoid secretion, antidiuretic hormone (ADH) which regulates water retention, oxytocin which causes uterine contraction and lactation, and prolactin which promotes milk production. Each hormone has specific functions, and deficiencies or excesses can result in various diseases treated through medication or manipulating hormone levels.
A chemical substance produced in the body that controls and regulates the activity of certain cells or organs. Many hormones are secreted by special glands, such as thyroid hormone produced by the thyroid gland.
The document summarizes the hormones of the pituitary gland. It discusses that the pituitary gland, also known as the master gland, controls other endocrine glands by secreting hormones. These hormones include growth hormone, thyroid stimulating hormone, adrenocorticotropic hormone, prolactin, luteinizing hormone, follicle stimulating hormone, oxytocin, and vasopressin. It provides details on the function and regulation of each hormone. Common diseases associated with hormonal imbalances are also mentioned.
The anterior pituitary gland, also called the adenohypophysis, is divided into two parts: the pars anterior and the tiny pars intermedia. The pars anterior contains five major cell types that secrete different hormones: somatotrophs secrete growth hormone, corticotrophs secrete ACTH, thyrotrophs secrete TSH, lactotrophs secrete prolactin, and gonadotrophs secrete LH and FSH. The hypothalamus controls hormone secretion in the anterior pituitary through releasing and inhibiting hormones that travel via the hypophyseal portal system and stimulate or suppress hormone production.
Hormones are chemical substances produced in one part of the body that travel through the bloodstream and cause changes to structures and functions in distant target organs. There are two main types of hormone receptors - cell surface receptors for water-soluble hormones that generate intracellular messengers, and intracellular receptors for lipid-soluble hormones that alter gene expression. Hormones regulate important bodily functions like growth, metabolism, mood, immune response, reproduction, and preparing the body for events like puberty or stress. The effects of hormones are controlled by their rates of secretion, transport, receptor levels in target tissues, and degradation.
The document summarizes key concepts about mammalian hormones. It lists the three major chemical groups that most hormones belong to: amines, peptides, and steroids. It explains that hormones can either promote or inhibit actions in target organs or many organs. Hormonal secretion is controlled by the hypothalamus and can occur in response to the presence of specific substances, other hormones, or nervous stimulation from the autonomic nervous system.
Insulin, glucagon, and diabetes mellitusbigboss716
The pancreas secretes two important hormones, insulin and glucagon, which regulate glucose, lipid, and protein metabolism. Insulin is secreted by beta cells in the pancreas and lowers blood glucose levels by promoting glucose uptake in muscle and fat cells and stimulating glycogen and fat synthesis in the liver. Glucagon is secreted by alpha cells and raises blood glucose levels by stimulating glycogenolysis and gluconeogenesis in the liver. Diabetes occurs when there is insufficient insulin secretion or insulin resistance, leading to high blood glucose levels and ketosis due to fat breakdown and acidosis.
Hormonal control of gametogenesis involves the hypothalamus releasing GnRH which acts on the anterior pituitary to release FSH and LH. In males, FSH acts on Sertoli cells to facilitate spermatogenesis while LH stimulates Leydig cells to produce testosterone which further stimulates spermatogenesis and causes secondary sex characteristics. Rising testosterone provides negative feedback to slow spermatogenesis. In females, FSH causes follicular development while LH triggers ovulation and the corpus luteum produces estrogen and progesterone, maintaining the endometrium lining during pregnancy.
The document summarizes key aspects of the endocrine system and hormone signaling. It describes two main coordinating systems - the endocrine system which secretes hormones to regulate slower processes like growth and metabolism, and the nervous system which uses fast electrical signals. Hormones are classified by their range and effects. The endocrine system uses hormones to coordinate processes in the body and maintain homeostasis via feedback loops, such as insulin and glucagon regulating blood glucose levels. Disorders like diabetes occur when these regulatory processes are disrupted.
The pituitary gland, located at the base of the brain, is divided into the anterior and posterior pituitary. The anterior pituitary secretes hormones that control other endocrine glands and is regulated by hormones from the hypothalamus. The posterior pituitary stores and releases oxytocin and antidiuretic hormone (ADH), which are produced in the hypothalamus and travel down nerve fibers to the posterior pituitary. Growth hormone, secreted by the anterior pituitary, promotes growth and protein synthesis throughout the body and has effects on carbohydrate and fat metabolism. Its secretion is regulated by the hypothalamus.
Hormones can be classified into four groups based on their mechanism of action. Group 1 hormones bind to intracellular receptors and include androgens, calcitriol, estrogens, glucocorticoids, and progestins. Group 2 hormones bind to cell surface receptors and use either cyclic AMP or cyclic GMP as second messengers, such as ACTH, ADH, and atrial natriuretic factor. Group 3 hormones also bind to cell surface receptors but use calcium or phosphatidyl inositols as second messengers like GnRH and TRH. Group 4 hormones signal through a kinase or phosphatase cascade as a second messenger, including insulin, GH, and prolactin.
The thyroid gland produces thyroid hormones that regulate metabolism. It takes up iodine to produce thyroglobulin, which is the precursor for the active hormones T3 and T4. Production of thyroid hormones is regulated by TSH from the pituitary, which is itself regulated by TRH from the hypothalamus in a negative feedback loop. Both hypothyroidism and hyperthyroidism can result from problems in this regulatory system and cause a variety of symptoms and health effects.
Hormones in human body , biological bases of behavior Anand Choudhary
This document provides an overview of hormones and their functions. It describes hormones as chemicals secreted by endocrine glands that influence other glands and organs. There are two major classes of hormones - protein hormones like insulin and glucagon, and steroid hormones derived from cholesterol like corticoids and sex steroids. The release of hormones is controlled by the hypothalamus and pituitary gland using negative feedback systems. Specific hormonal disorders that impact sexual development and characteristics are also discussed, as well as the effects of pheromones on behavior in animals and humans.
The endocrine system regulates bodily functions through hormones secreted into the bloodstream. Hormones are chemical messengers produced by endocrine glands that travel through the body and bind to target cells. The endocrine system maintains homeostasis through feedback loops that regulate hormone production and secretion. Hormone receptors on target cells determine the cells' response, and the endocrine system controls hormone levels through patterns of secretion including pulsatile, acute, and cyclic release.
organic biologically active compounds of different chemical nature that are produced by the endocrine glands, enter directly into blood and accomplish humoral regulation of the metabolism of compounds and functions on the organism level.
Hormones can be classified in several ways based on their chemical composition, mechanism of action, target effects, and whether they stimulate other endocrine glands. The three main types are steroid hormones, peptide hormones, and amine hormones. Steroid hormones are lipophilic and act via nuclear receptors. Peptide hormones are hydrophilic and act through cell surface receptors and secondary messengers like cAMP. Amine hormones have properties of both peptides and steroids. Hormones also differ in their local versus general actions, kinetic versus metabolic effects, and whether they stimulate other glands via tropic hormones or act directly on tissues.
GENERAL MECHANISM OF PEPTIDE AND STEROID HORMONE ACTION.pdfApoorva Rajagopal
Hormones are a type of signaling molecules that are produced by the endocrine glands. They are natural organic substance produced in minute quantity to regulate growth, metabolism and other functions.
Hormones are chemical messengers that are produced in endocrine glands and secreted into the bloodstream to control metabolic and biological activities in target cells. They can be classified based on their chemical nature as amino acid derivatives, proteins/peptides, or steroids, and based on their mechanism of action as group I hormones that bind intracellular receptors or group II hormones that bind cell surface receptors and trigger secondary messengers. Key hormones include reproductive hormones like estrogen and testosterone; thyroid hormones; adrenal hormones like cortisol and aldosterone; calcium regulating hormones calcitriol, PTH, and calcitonin; and others. Abnormalities in hormone levels can lead to diseases and disorders.
The document discusses adrenocortical hormones and their synthesis and secretion. It covers the following key points:
1. The adrenal cortex secretes corticosteroids including mineralocorticoids like aldosterone and glucocorticoids like cortisol.
2. Aldosterone regulates sodium and potassium levels while cortisol regulates glucose levels and has anti-inflammatory effects.
3. Corticosteroid synthesis occurs in the zona glomerulosa, zona fasciulata, and zona reticularis layers of the adrenal cortex from cholesterol.
4. ACTH stimulates cortisol secretion which is regulated by a negative feedback loop with the hypothalamus and
Basic Introduction to the vast science of the endocrine glands and their interactions. A brief review into the physiological processes that result in endocrine disorders.
Hormones are signaling molecules produced by glands that are transported via bloodstream to target distant organs to regulate physiology. They are classified as proteinaceous (peptide) hormones or non-proteinaceous (steroid) hormones. Some important peptide hormones include insulin which regulates carbohydrate and fat metabolism, glucagon which raises blood sugar levels, adrenocorticotropic hormone (ACTH) which regulates glucocorticoid secretion, antidiuretic hormone (ADH) which regulates water retention, oxytocin which causes uterine contraction and lactation, and prolactin which promotes milk production. Each hormone has specific functions, and deficiencies or excesses can result in various diseases treated through medication or manipulating hormone levels.
A chemical substance produced in the body that controls and regulates the activity of certain cells or organs. Many hormones are secreted by special glands, such as thyroid hormone produced by the thyroid gland.
The document summarizes the hormones of the pituitary gland. It discusses that the pituitary gland, also known as the master gland, controls other endocrine glands by secreting hormones. These hormones include growth hormone, thyroid stimulating hormone, adrenocorticotropic hormone, prolactin, luteinizing hormone, follicle stimulating hormone, oxytocin, and vasopressin. It provides details on the function and regulation of each hormone. Common diseases associated with hormonal imbalances are also mentioned.
The anterior pituitary gland, also called the adenohypophysis, is divided into two parts: the pars anterior and the tiny pars intermedia. The pars anterior contains five major cell types that secrete different hormones: somatotrophs secrete growth hormone, corticotrophs secrete ACTH, thyrotrophs secrete TSH, lactotrophs secrete prolactin, and gonadotrophs secrete LH and FSH. The hypothalamus controls hormone secretion in the anterior pituitary through releasing and inhibiting hormones that travel via the hypophyseal portal system and stimulate or suppress hormone production.
Hormones are chemical substances produced in one part of the body that travel through the bloodstream and cause changes to structures and functions in distant target organs. There are two main types of hormone receptors - cell surface receptors for water-soluble hormones that generate intracellular messengers, and intracellular receptors for lipid-soluble hormones that alter gene expression. Hormones regulate important bodily functions like growth, metabolism, mood, immune response, reproduction, and preparing the body for events like puberty or stress. The effects of hormones are controlled by their rates of secretion, transport, receptor levels in target tissues, and degradation.
The document summarizes key concepts about mammalian hormones. It lists the three major chemical groups that most hormones belong to: amines, peptides, and steroids. It explains that hormones can either promote or inhibit actions in target organs or many organs. Hormonal secretion is controlled by the hypothalamus and can occur in response to the presence of specific substances, other hormones, or nervous stimulation from the autonomic nervous system.
Insulin, glucagon, and diabetes mellitusbigboss716
The pancreas secretes two important hormones, insulin and glucagon, which regulate glucose, lipid, and protein metabolism. Insulin is secreted by beta cells in the pancreas and lowers blood glucose levels by promoting glucose uptake in muscle and fat cells and stimulating glycogen and fat synthesis in the liver. Glucagon is secreted by alpha cells and raises blood glucose levels by stimulating glycogenolysis and gluconeogenesis in the liver. Diabetes occurs when there is insufficient insulin secretion or insulin resistance, leading to high blood glucose levels and ketosis due to fat breakdown and acidosis.
Hormonal control of gametogenesis involves the hypothalamus releasing GnRH which acts on the anterior pituitary to release FSH and LH. In males, FSH acts on Sertoli cells to facilitate spermatogenesis while LH stimulates Leydig cells to produce testosterone which further stimulates spermatogenesis and causes secondary sex characteristics. Rising testosterone provides negative feedback to slow spermatogenesis. In females, FSH causes follicular development while LH triggers ovulation and the corpus luteum produces estrogen and progesterone, maintaining the endometrium lining during pregnancy.
The document summarizes key aspects of the endocrine system and hormone signaling. It describes two main coordinating systems - the endocrine system which secretes hormones to regulate slower processes like growth and metabolism, and the nervous system which uses fast electrical signals. Hormones are classified by their range and effects. The endocrine system uses hormones to coordinate processes in the body and maintain homeostasis via feedback loops, such as insulin and glucagon regulating blood glucose levels. Disorders like diabetes occur when these regulatory processes are disrupted.
The pituitary gland, located at the base of the brain, is divided into the anterior and posterior pituitary. The anterior pituitary secretes hormones that control other endocrine glands and is regulated by hormones from the hypothalamus. The posterior pituitary stores and releases oxytocin and antidiuretic hormone (ADH), which are produced in the hypothalamus and travel down nerve fibers to the posterior pituitary. Growth hormone, secreted by the anterior pituitary, promotes growth and protein synthesis throughout the body and has effects on carbohydrate and fat metabolism. Its secretion is regulated by the hypothalamus.
Hormones can be classified into four groups based on their mechanism of action. Group 1 hormones bind to intracellular receptors and include androgens, calcitriol, estrogens, glucocorticoids, and progestins. Group 2 hormones bind to cell surface receptors and use either cyclic AMP or cyclic GMP as second messengers, such as ACTH, ADH, and atrial natriuretic factor. Group 3 hormones also bind to cell surface receptors but use calcium or phosphatidyl inositols as second messengers like GnRH and TRH. Group 4 hormones signal through a kinase or phosphatase cascade as a second messenger, including insulin, GH, and prolactin.
The thyroid gland produces thyroid hormones that regulate metabolism. It takes up iodine to produce thyroglobulin, which is the precursor for the active hormones T3 and T4. Production of thyroid hormones is regulated by TSH from the pituitary, which is itself regulated by TRH from the hypothalamus in a negative feedback loop. Both hypothyroidism and hyperthyroidism can result from problems in this regulatory system and cause a variety of symptoms and health effects.
Hormones in human body , biological bases of behavior Anand Choudhary
This document provides an overview of hormones and their functions. It describes hormones as chemicals secreted by endocrine glands that influence other glands and organs. There are two major classes of hormones - protein hormones like insulin and glucagon, and steroid hormones derived from cholesterol like corticoids and sex steroids. The release of hormones is controlled by the hypothalamus and pituitary gland using negative feedback systems. Specific hormonal disorders that impact sexual development and characteristics are also discussed, as well as the effects of pheromones on behavior in animals and humans.
The endocrine system regulates bodily functions through hormones secreted into the bloodstream. Hormones are chemical messengers produced by endocrine glands that travel through the body and bind to target cells. The endocrine system maintains homeostasis through feedback loops that regulate hormone production and secretion. Hormone receptors on target cells determine the cells' response, and the endocrine system controls hormone levels through patterns of secretion including pulsatile, acute, and cyclic release.
The endocrine system regulates and integrates various physiological functions through hormones. Hormones are chemical messengers that are secreted into the bloodstream by endocrine glands and travel to target cells. There are two main classes of hormones - steroid hormones which are lipid soluble and can pass through cell membranes, and peptide hormones which are water soluble and bind to surface receptors of target cells. The endocrine system maintains homeostasis through feedback mechanisms that regulate hormone secretion and receptor levels.
Hormones are chemical messengers that are secreted by endocrine cells and glands. They regulate functions in target cells by binding to specific receptors. There are two main classes - peptide hormones which are proteins or glycoproteins, and steroid hormones which are derived from cholesterol. Hormones trigger cellular responses through signal transduction pathways and regulate important bodily processes like growth, metabolism, and reproduction.
This document provides an overview of endocrinology and the endocrine system. It discusses that endocrinology is the study of hormones, their receptors, and signaling pathways. It describes the major endocrine glands and their hormone functions. It also summarizes the different types of hormone actions, classifications, synthesis, secretion, transport, and feedback control of hormone levels.
The endocrine system coordinates and regulates bodily functions through the secretion of hormones from various glands directly into the bloodstream. The major glands include the hypothalamus, pituitary, thyroid, parathyroids, adrenals, pancreas, testes, and ovaries. The hypothalamus controls the pituitary gland which secretes hormones that regulate other endocrine glands. Hormones maintain homeostasis, metabolism, sexual development, and reproduction. Glandular secretions are influenced by negative and positive feedback loops in the endocrine system.
The endocrine system coordinates and regulates bodily functions through chemical messengers called hormones. It includes glands like the hypothalamus, pituitary, thyroid, parathyroids, adrenals, pancreas, testes, and ovaries. The hypothalamus produces releasing and inhibiting hormones that control the pituitary. The pituitary secretes hormones that control other glands. Hormones regulate metabolism, growth and development, tissue function, sexual function, reproduction, sleep, and mood. Glandular secretions and hormone actions are precisely balanced to maintain homeostasis.
This document discusses endocrinology and hormones. It defines endocrinology as the science of endocrine glands and their functions and disorders. Endocrine glands secrete hormones directly into the bloodstream without ducts. Hormones are chemical messengers that affect cells distant from their site of secretion. There are two types of hormonal action - through intracellular mediators like cAMP or through gene mediators by binding to DNA. Major endocrine glands and their hormones are described.
The document discusses endocrinology and the endocrine system. It provides details on:
- The endocrine system uses hormones to control physiological processes through transmitters, signals, and receivers.
- The main endocrine glands include the pituitary, thyroid, parathyroid, thymus, adrenal, and reproductive glands.
- Each gland produces specific hormones that target certain cells and tissues to regulate key body functions like growth, metabolism, sexual development, stress response, and more.
- The hormones work through feedback loops controlled by the hypothalamus and pituitary gland.
Arnold Berthold conducted early endocrine experiments in 1849 showing that castration caused changes in roosters that could be reversed by testicular extracts, demonstrating the endocrine role of the testes. Claude Bernard established that hormones travel via blood to regulate the internal environment. The endocrine and nervous systems both integrate stimuli and responses but differ in their modes of communication. Hormones are categorized into peptides/proteins, amino acid derivatives, steroids, and fatty acid derivatives. Key aspects of hormone function, synthesis, regulation, and control are discussed.
There are two types of animal development: indirect and direct. Indirect development involves one or more larval forms before reaching adulthood, while direct development results in offspring that resemble smaller versions of the parents from birth. Indirect development includes a process called metamorphosis where the animal transforms between immature and adult forms. Mammals typically undergo direct development where the embryo develops inside the mother's uterus. The endocrine system uses hormones to regulate bodily functions and homeostasis. Hormones can be peptides or steroids and act through receptors in target cells to elicit metabolic responses.
Classification of hormones, mechanism of hormone action, structure
and functions of pituitary gland, thyroid gland, parathyroid gland, adrenal gland, pancreas, pineal gland, thymus and their disorders.
The document provides an overview of the endocrine system. It describes that the endocrine and nervous systems work together to coordinate body functions. The endocrine system releases hormones to control activities, unlike the nervous system which uses neurotransmitters. There are two types of glands - exocrine glands which secrete through ducts, and endocrine glands which secrete directly into blood. Key endocrine glands and tissues discussed include the pituitary, thyroid, parathyroid, adrenal glands, pancreas, ovaries, testes and others. The roles, secretions and regulations of various hormones are explained in detail.
This document discusses hormones, including their mechanism of action, types, importance, and factors that affect hormone levels. Hormones are chemical messengers that are secreted from endocrine glands and carry signals through the bloodstream to target organs. They regulate important bodily functions like growth, metabolism, and reproduction. Imbalances in hormone levels can lead to health issues like diabetes or thyroid disorders.
Hormones are chemical messengers that are secreted into the bloodstream by endocrine glands and target specific organs. The endocrine system regulates bodily functions through hormones, while the nervous system uses nerves. There are two main types of hormones - lipid-soluble hormones like steroids which diffuse through cell membranes, and water-soluble hormones like peptides which bind to surface receptors. Major endocrine glands include the pituitary, thyroid, parathyroids, pancreas, adrenals, ovaries/testes, which regulate growth, metabolism, sexual development, and other processes. Hormones bind to receptors on target cells and trigger physiological responses through various mechanisms of action.
The pituitary gland, located at the base of the brain, is responsible for regulating many important bodily processes through the hormones it produces and secretes. Known as the "master gland", it takes signals from the brain and controls other endocrine glands. Composed of three lobes, the anterior pituitary secretes hormones that stimulate growth, thyroid function, adrenal function, lactation, and reproduction. The posterior pituitary stores and releases oxytocin and vasopressin. Together with the hypothalamus, the pituitary regulates a negative feedback system to maintain hormone levels within normal ranges.
Hormones and behavior is the scientific study of interaction between hormone...VandanaGaur15
Hormones may modulate the expression of behaviour, but are not causes of behaviour. Behaviour is mainly driven by internal and environmental stimuli, with different stimuli eliciting different behaviors. For example, courtship behavior occurs when a male and a female in reproductive condition meet each other.In this way, the brain adjusts its performance and control of behavior in response to a changing environment. Hormones are important agents of protection and adaptation, but stress and stress hormones, such as the glucocorticoid cortisol, can also alter brain function, including the brain's capacity to learn.
The document provides an overview of intensive care unit (ICU) training. It defines the ICU and its purpose of providing life support and monitoring for critically ill patients. It discusses types of ICUs including postoperative, pediatric, and neonatal units. Key aspects of ICU care covered include vital sign management, oxygen therapy, common procedures, scales used to assess patients, and equipment. Invasive and noninvasive monitoring techniques are also outlined.
This document defines vitamins and minerals, classifies different vitamins, discusses their sources and functions. It describes vitamin and mineral deficiencies and their symptoms. Key points include: vitamins are organic compounds necessary for health; there are two groups of vitamins - water and fat soluble; common vitamins include A, B, C, D, E and K; deficiencies can cause diseases like scurvy and rickets; minerals are inorganic elements from the earth's crust essential for body structure and processes.
This document defines vitamins and minerals, classifies different vitamins, discusses their sources and functions. It describes vitamin and mineral deficiencies and their symptoms. Key points include: vitamins are organic compounds necessary for health; there are two groups of vitamins - water and fat soluble; common vitamins include A, B complex, C, D, E and K. Minerals are inorganic elements needed for growth; important minerals are calcium, iron, iodine and phosphorus. The document provides details on specific vitamins and minerals.
Proteins are essential components of every cell and are needed for the body's structures, functions, and regulation. They are made up of amino acids and provide many critical functions. Important protein sources include meat, eggs, dairy, and beans. Digestion of proteins begins in the stomach and is completed in the small intestine. Lipids are fats and oils that provide stored energy and serve other crucial roles like insulation. Essential fatty acids must be obtained through diet as the body cannot produce them. Lipid digestion begins in the stomach and small intestine with the help of enzymes.
The document outlines a nutrition course covering topics such as carbohydrates, proteins, vitamins, minerals and water. It also discusses why health workers study nutrition and some common nutrition-related health problems. Key points include definitions of food, nutrition, diet and malnutrition. Carbohydrate digestion and metabolism are explained in detail. Causes and signs of malnutrition and malabsorption syndrome are also provided.
This document discusses different patterns of inheritance including recessive, dominant, autosomal, and sex-linked traits. It provides examples of several genetic diseases that are inherited through autosomal recessive or dominant patterns including cystic fibrosis, Gaucher disease, osteogenesis imperfecta type 1, and Huntington's disease. It describes the genes involved, typical symptoms, and inheritance patterns for each of these conditions.
This document provides guidelines for the management of cardiovascular diseases during pregnancy from the European Society of Cardiology (ESC). It was developed by an international task force and endorsed by several societies. The guidelines cover epidemiology, physiological adaptations during pregnancy, pre-pregnancy counseling, cardiovascular diagnosis and testing considerations in pregnancy, genetic testing, fetal assessment, interventions in mothers, timing and mode of delivery, postpartum care, breastfeeding, and infective endocarditis management. The goal is to provide recommendations to optimize outcomes for both maternal and fetal health in women with heart disease who are pregnant or wish to become pregnant.
The respiratory tract is divided into three segments: the upper respiratory tract, respiratory airways, and lungs. The upper respiratory tract includes the nose, paranasal sinuses, and throat. The respiratory airways include the larynx, trachea, bronchi, and bronchioles. The lungs contain the respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli, which are the sites of gas exchange with the blood. The respiratory tract is susceptible to both upper and lower respiratory infections caused by viruses and bacteria. Common upper respiratory infections include strep throat, caused by Streptococcus pyogenes, which if left untreated can lead to rheumatic fever or glomerulone
This document discusses preeclampsia, a hypertensive disorder that occurs during pregnancy. It defines preeclampsia as hypertension and proteinuria arising after 20 weeks of gestation. Preeclampsia can progress to eclampsia, which involves seizures. Risk factors include primigravidity and family history. Symptoms include headaches and visual disturbances. Diagnosis involves blood pressure monitoring and urine analysis. Delivery is the only cure for preeclampsia. Management focuses on controlling blood pressure, monitoring the fetus, and timely delivery. Complications for the mother include eclampsia, HELLP syndrome, and stroke, while risks for the baby include growth restriction and stillbirth.
This document describes the process and principles of immunofluorescence assays. It discusses both direct and indirect immunofluorescence techniques. Direct immunofluorescence involves applying fluorescently-labeled antibodies directly to tissue samples to detect antigens. Indirect immunofluorescence uses unlabeled patient antibodies detected using secondary fluorescently-labeled anti-human antibodies to identify antibodies in serum. The document provides detailed steps for performing indirect immunofluorescence assays including preparing antigen slides, making serum dilutions, incubation, washing, and examination under a fluorescence microscope.
10 Benefits an EPCR Software should Bring to EMS Organizations Traumasoft LLC
The benefits of an ePCR solution should extend to the whole EMS organization, not just certain groups of people or certain departments. It should provide more than just a form for entering and a database for storing information. It should also include a workflow of how information is communicated, used and stored across the entire organization.
These lecture slides, by Dr Sidra Arshad, offer a simplified look into the mechanisms involved in the regulation of respiration:
Learning objectives:
1. Describe the organisation of respiratory center
2. Describe the nervous control of inspiration and respiratory rhythm
3. Describe the functions of the dorsal and respiratory groups of neurons
4. Describe the influences of the Pneumotaxic and Apneustic centers
5. Explain the role of Hering-Breur inflation reflex in regulation of inspiration
6. Explain the role of central chemoreceptors in regulation of respiration
7. Explain the role of peripheral chemoreceptors in regulation of respiration
8. Explain the regulation of respiration during exercise
9. Integrate the respiratory regulatory mechanisms
10. Describe the Cheyne-Stokes breathing
Study Resources:
1. Chapter 42, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 36, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 13, Human Physiology by Lauralee Sherwood, 9th edition
Nano-gold for Cancer Therapy chemistry investigatory projectSIVAVINAYAKPK
chemistry investigatory project
The development of nanogold-based cancer therapy could revolutionize oncology by providing a more targeted, less invasive treatment option. This project contributes to the growing body of research aimed at harnessing nanotechnology for medical applications, paving the way for future clinical trials and potential commercial applications.
Cancer remains one of the leading causes of death worldwide, prompting the need for innovative treatment methods. Nanotechnology offers promising new approaches, including the use of gold nanoparticles (nanogold) for targeted cancer therapy. Nanogold particles possess unique physical and chemical properties that make them suitable for drug delivery, imaging, and photothermal therapy.
Know the difference between Endodontics and Orthodontics.Gokuldas Hospital
Your smile is beautiful.
Let’s be honest. Maintaining that beautiful smile is not an easy task. It is more than brushing and flossing. Sometimes, you might encounter dental issues that need special dental care. These issues can range anywhere from misalignment of the jaw to pain in the root of teeth.
Travel Clinic Cardiff: Health Advice for International TravelersNX Healthcare
Travel Clinic Cardiff offers comprehensive travel health services, including vaccinations, travel advice, and preventive care for international travelers. Our expert team ensures you are well-prepared and protected for your journey, providing personalized consultations tailored to your destination. Conveniently located in Cardiff, we help you travel with confidence and peace of mind. Visit us: www.nxhealthcare.co.uk
Osteoporosis - Definition , Evaluation and Management .pdfJim Jacob Roy
Osteoporosis is an increasing cause of morbidity among the elderly.
In this document , a brief outline of osteoporosis is given , including the risk factors of osteoporosis fractures , the indications for testing bone mineral density and the management of osteoporosis
Cell Therapy Expansion and Challenges in Autoimmune DiseaseHealth Advances
There is increasing confidence that cell therapies will soon play a role in the treatment of autoimmune disorders, but the extent of this impact remains to be seen. Early readouts on autologous CAR-Ts in lupus are encouraging, but manufacturing and cost limitations are likely to restrict access to highly refractory patients. Allogeneic CAR-Ts have the potential to broaden access to earlier lines of treatment due to their inherent cost benefits, however they will need to demonstrate comparable or improved efficacy to established modalities.
In addition to infrastructure and capacity constraints, CAR-Ts face a very different risk-benefit dynamic in autoimmune compared to oncology, highlighting the need for tolerable therapies with low adverse event risk. CAR-NK and Treg-based therapies are also being developed in certain autoimmune disorders and may demonstrate favorable safety profiles. Several novel non-cell therapies such as bispecific antibodies, nanobodies, and RNAi drugs, may also offer future alternative competitive solutions with variable value propositions.
Widespread adoption of cell therapies will not only require strong efficacy and safety data, but also adapted pricing and access strategies. At oncology-based price points, CAR-Ts are unlikely to achieve broad market access in autoimmune disorders, with eligible patient populations that are potentially orders of magnitude greater than the number of currently addressable cancer patients. Developers have made strides towards reducing cell therapy COGS while improving manufacturing efficiency, but payors will inevitably restrict access until more sustainable pricing is achieved.
Despite these headwinds, industry leaders and investors remain confident that cell therapies are poised to address significant unmet need in patients suffering from autoimmune disorders. However, the extent of this impact on the treatment landscape remains to be seen, as the industry rapidly approaches an inflection point.
How to Control Your Asthma Tips by gokuldas hospital.Gokuldas Hospital
Respiratory issues like asthma are the most sensitive issue that is affecting millions worldwide. It hampers the daily activities leaving the body tired and breathless.
The key to a good grip on asthma is proper knowledge and management strategies. Understanding the patient-specific symptoms and carving out an effective treatment likewise is the best way to keep asthma under control.
Co-Chairs, Val J. Lowe, MD, and Cyrus A. Raji, MD, PhD, prepared useful Practice Aids pertaining to Alzheimer’s disease for this CME/AAPA activity titled “Alzheimer’s Disease Case Conference: Gearing Up for the Expanding Role of Neuroradiology in Diagnosis and Treatment.” For the full presentation, downloadable Practice Aids, and complete CME/AAPA information, and to apply for credit, please visit us at https://bit.ly/3PvVY25. CME/AAPA credit will be available until June 28, 2025.
Are you looking for a long-lasting solution to your missing tooth?
Dental implants are the most common type of method for replacing the missing tooth. Unlike dentures or bridges, implants are surgically placed in the jawbone. In layman’s terms, a dental implant is similar to the natural root of the tooth. It offers a stable foundation for the artificial tooth giving it the look, feel, and function similar to the natural tooth.
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptxHolistified Wellness
We’re talking about Vedic Meditation, a form of meditation that has been around for at least 5,000 years. Back then, the people who lived in the Indus Valley, now known as India and Pakistan, practised meditation as a fundamental part of daily life. This knowledge that has given us yoga and Ayurveda, was known as Veda, hence the name Vedic. And though there are some written records, the practice has been passed down verbally from generation to generation.
2. Learning Outcomes.
• By the end of this lecture you should be able to:
• 1. Describe the different types of hormones and their key
actions.
• 2. Explain the neural control of hormone release.
• 3. Describe specific hormonal disorders.
• 4. Explain the term 'pheromone' and provide examples of
pheromones in action.
4. How Do Hormones Work?
• Hormones travel through the blood and influence the
activity of other glands and organs.
• They produce short- and long-term changes in various
cells and organs by acting like neurotransmitters at
metabotropic receptors.
• A hormone can only influence cells that have specific
target receptors for that particular hormone.
5. Types of Hormones.
• Endocrine glands produce 2 major classes of hormones
(and several other types as well):
• 1. Protein hormones: These comprise amino acids, those
that are only several amino acids in length are called
peptide hormones, whereas larger ones are called
polypeptide hormones. They include:
• Insulin: Made in the pancreas, it increases the entry of
glucose into the cells, and regulates fat storage.
• Glucagons: Made in the pancreas, are responsible for
increasing the conversion of stored fats to blood
glucose.
• Leptin: Produced by the fat cells, it informs the brain how
much fat is contained in the body.
6. Leptin in Action.
When leptin levels are
high appetite is
decreased.
When leptin levels are low
appetite is increased and
bodily activity is reduced.
Mice who inherit 2 copies
of the defective ob gene
are unable to produce
leptin and so overeat.
Injections of leptin reduce
their food intake.
7. 2. Steroid Hormones.
• These are derived from cholesterol from the diet and
exert their effects in two ways:
• i) They bind directly to membrane receptors.
• ii) As they are fat soluble they pass through cell
membranes where they attach to receptors in the
cytoplasm. Here they determine gene expression.
• There are several types of steroid hormones:
• a) Corticoids.
• Glucocorticoids (principally cortisol) are released by the
adrenal glands in response to stress.
• They increase the breakdown of fats and proteins into
glucose to trigger escape or defense ("fight or flight").
• Mineralocorticoids (e.g. aldosterone) are also produced
by the adrenal glands and reduce salt secretion in the
kidneys.
8. b) Sex Steroids.
• These are released mainly by the ovaries and testes but
also by the adrenal glands. They comprise:
• Androgens: Testosterone is produced in large amounts in
males and has masculinising and defeminising effects;
maintaining male secondary sexual characteristics and
promoting courtship, aggressive and sexual behaviours.
• Estrogens: Estradiol is produced in large amounts in
females and has feminising effects, promoting female
secondary sexual characteristics, water retention,
calcium metabolism, sexual behaviour and maternal
behaviours.
• Progesterone prepares the uterus for the implantation of
a fertilised ovum and regulates the stages of pregnancy.
9. Misunderstandings.
• According to Nelson (2000), there are several
misunderstandings surrounding hormones:
• 1. Sex steroids are sex-specific: In fact both males and
females produce androgens and estrogens though their
relative concentrations differ.
• 2. Individual differences in behaviour and physiology
reflect differences in hormone concentration: While
overall concentration is indeed important, of equal
importance is the receptivity of the cells to the hormone.
• A high hormone concentration will have little effect if
cells lack receptivity, an excellent example of this is
Androgen Insensitivity Syndrome.
10. Control of Hormone Release.
• Hormone release is controlled by two key structures in
the brain:
• 1. Hypothalamus: This is located at the base of the brain
and consists of several interconnected nuclei.
• The hypothalamic nuclei synthesise releasing hormones
that either stimulate or inhibit the release of hormones
from the pituitary gland.
• The hypothalamus also secretes oxytocin and
vasopressin which travel to the posterior pituitary gland.
This then releases them into the bloodstream in
response to certain neural signals.
11. Negative Feedback in the
Hypothalamus.
• The hypothalamus maintains fairly constant levels of
hormones because it operates a negative feedback
system. E.g:
Hypothalamus
Thyroid Stimulating Hormone-
Releasing Hormone
Anterior pituitary
Thyroid gland
Thyroid Stimulating Hormone
Thyroid
hormones
excitatory
inhibitory
12. 2. Pituitary Gland.
• This is called ‘the
master gland’ as it
produces at least 10
hormones which
influence the other
endocrine glands via
the hypothalamus.
• It consists of two
separate regions.
• The anterior pituitary
and the posterior
pituitary each share
distinct connections
with the
hypothalamus.
hypothalamus
Posterior
pituitary
Vasopressin
and oxytocin
GH, ACTH, TSH,
FSH, LH and
prolactin
Anterior
pituitary
Blood
supply
13. Anterior Pituitary Gland.
• Hormones produced here are referred to as tropic as
they stimulate various processes:
• Luteinizing Hormone (LH): Increases production of
progesterone and stimulates ovulation in females. In
males it increases production of testosterone.
• Follicle-Stimulating Hormone (FSH): Increases
production of estrogen and maturation of the ovum (in
females) and sperm (in males).
• Thyroid-Stimulating Hormone (TSH): Controls secretions
of the thyroid gland.
• Growth Hormone (GH): Increases body growth.
• Prolactin: Controls milk production in females.
• Adrenocorticotropic Hormone (ACTH): Controls
secretions of the adrenal gland.
14. Posterior Pituitary Gland.
• This stores oxytocin which controls uterine contractions,
milk release, parental behaviours and orgasm.
• It also stores vasopressin (also known as antidiuretic
hormone) which constricts blood vessels, raises blood
pressure, and decreases urine volume.
15. Hormones and Behaviour.
• Hormones do not cause a particular behaviour to
change, rather they change the likelihood that a
particular behaviour will occur in an appropriate
environmental context.
• Certain behaviours can also influence hormone levels,
e.g. testosterone levels can rise or fall depending upon
whether a contest has been won or lost.
• This is a ‘chicken and egg’ problem, i.e. do hormones
influence behaviour by directly affecting the brain, or
does behaving in a particular manner influence hormone
production?
• In order to decide we can use three techniques:
16. Experiments to Test
Hormone/Behaviour
Relationships.
• 1. If we remove the source of a particular hormone then
a behaviour that is assumed to depend upon that
hormone should disappear. E.g removal of testosterone
by castration dramatically reduces sexual desire and
aggression in many male animals.
• 2. Once a behaviour has ceased following hormone
removal, we can restore hormone function and see if the
behaviour returns. E.g administration of testosterone to
castrated adult males restores aggressive behaviours
and the mating urge.
• 3. If hormones and certain behaviours are related, then
we should expect that alterations in the relative
concentration of a hormone should produce related
alterations in a behaviour. E.g aggression should be
higher when circulating levels of testosterone are higher.
17. Human Hormone Disorders.
• 1. Congenital Adrenal Hyperplasia (CAH).
• This is a genetic disorder producing enzyme deficiency
in the adrenal glands.
• The glands are unable to produce sufficient quantities of
cortisol which normally inhibits the release of
adrenocorticotropic hormone (ACTH) which promotes
sex-steroid synthesis.
• ACTH is thus produced in large amounts and the foetus
is exposed to excessive amounts of androgens which
have a masculinising effect.
• Affected females display masculinised genitals and
behaviour. Affected males may show precocious puberty.
18. 2. Androgen-Insensitivity Syndrome
(AIS).
• An X-linked recessive disorder
(affecting only males) in which
androgen receptors in the cells
do not function.
• The male brain and body remain
unresponsive to androgens and
are feminised due to maternal
estrogens.
• At puberty the testes do not
descend and secondary female
sexual characteristics appear
due to circulating estrogens.
• Individuals are often reared as
girls and do not discover that
they are ‘male’ until they fail to
menstruate at puberty.
19. 3. Idiopathic Hypogonadotropic
Hypogonadism (IHH):
• This is caused by the insufficient release of gonadotropin
releasing hormone from the hypothalamus.
• It is sometimes referred to as ‘Kallman’s Syndrome’.
• Affected males are genetically normal, but do not receive
sufficient testosterone before birth.
• Their genitals remain relatively unaffected due to the
influence of maternal androgens, but at puberty
secondary male sex characteristics fail to appear.
20. 4. Turner’s Syndrome.
• This syndrome was first described by Turner (1938).
• It only affects females in which all or part of one X
chromosome is deleted.
• This leads to a failure in ovary development, and
produces short stature and physical anomalies such as
webbing of the neck.
• Externally, such individuals appear female but as they
fail to produce female sex hormones they remain
sexually immature unless provided with hormone
replacements.
• They remain infertile.
21. 4. 5α- Reductase Deficiency.
• This is a deficiency of the enzyme 5α-reductase which
normally converts testosterone into dihydrotestosterone.
• As dihydrotestosterone is principally responsible for
masculinising the external genitals before birth, males
with this syndrome are born with ambiguous genitalia
and undescended testes.
• They are often mistaken for females at birth and reared
as such.
• However at puberty when exposed to large amounts of
testosterone their body and external genitals become
more masculine.
22. Pheromones.
• These are chemicals derived from sex hormones which are
manufactured and released by the apocrine glands.
• They are released into the environment via sweat and
urine where they are detected by individuals of the same
species in whom they activate specific physiological and
behavioural responses.
• The following effects have been noted in animals:
23. Pheromone Effects in Animals.
• Lee-Boot effect: When groups of female mice are housed
together their estrus cycles slow down and stop.
• Whitten effect: If groups of female mice are then
exposed to an adult male mouse (or to the odour of his
urine) they begin estrus again and their cycles become
synchronised.
• Similar menstrual synchrony has been reported in human
females sharing accommodation.
• Vandenburg effect: The presence of an unrelated adult
male causes the acceleration of puberty in female rats.
This has also been reported for human females in the
presence of a stepfather.
• Bruce effect: When a pregnant female mouse is housed
with a male mouse who is not the father the pregnancy is
likely to fail and she quickly comes into estrus again.
24. Effects of Human Pheromones.
• At puberty, pheromones derived from androgens act as
sexual attractants. E.g. Thorne et al., (2002) found that
non-pill using females unknowingly exposed to male
pheromones gave higher attractiveness ratings to
photographs of males faces.