Exam 3 study guide CHAPTER 10 What are hormones How do they differ from neurotransmitters think site of action and distance travelled from release site Are they made by the brain peripheral organs or both o Hormones travel through bloodstream so they effect the entire body Hormone levels adapt and respond to environmental changes Hormones are made by the brain AND peripheral organs What are the 3 main classes of hormones o Protein Hormones Peptides mostly made in the brain Hard to get in and out of blood brain barrier o Amine Hormones Neurotransmitters Mostly made peripherally in body o Steroid Hormones Can pass through blood brain barrier because they re fatty How do the classic mechanisms of hormone action differ between protein hormones and steroid hormones think where the receptors are located and what effects they lead to in the cell o Protein Hormone Action Protein hormone receptors embedded in the cell membrane bind to the hormone activating a second messenger system that affects various processes inside the target cell o Steroid Hormone Action Steroid hormones diffuse passively in binding to large receptors molecules in target cells The steroid receptor complex then binds to DNA altering the expression of certain genes a so called genomic effect Slower than protein hormone action Know how hormone release is stimulated starting at the hypothalamus pituitary and ending at the peripheral endocrine gland testis ovary etc Which site produces releasing hormones Tropic hormones o Anterior Pituitary Neuroendocrine in the Hypothalamus makes releasing hormones Releasing hormones are sent to the anterior pituitary glands Hormone producing cells n the anterior pituitary respond by releasing or inhibiting the release of their own hormones tropic hormones Tropic hormones travel through the bloodstream and regulate endocrine glands throughout the body What is the difference between how hormones are released from anterior and posterior pituitary Which 2 hormones are released from the posterior pituitary Hypothalamic hormones act on pituitary pituitary releases tropic o Anterior Pituitary hormones o Posterior Pituitary Peptide hormones oxytocin and vasopressin are made in hypothalamus Oxytocin and vasopressin neurons also project widely throughout brain and regulate behavior Neuroendocrine cell bodies in hypothalamus produce Oxytocin and Vasopressin Axons from these neurons pass through pituitary stalk Terminate on capillaries of posterior pituitary during action potential oxytocin or vasopressin are released from terminal directly into bloodstream Know basics of sex determination sex chromosomes SRY gene gonadal differentiation o Sex Chromosomes If sperm carries an X the baby will be female If sperm carries a Y the baby will be male o SRY genes Sex determining Region of the Y chromosome Without SRY gene gonads become ovaries o Gonadal Differentiation 6 weeks after conception gonads are undifferentiated testis determining factor protein develops gonads into tests Know which sex is the default and which results from action of SRY gene o SRY Gene present Testis determining factor protein Gonads develop into tests o Without SRY Gene Gonads become ovaries What are organizational and activational effects of hormones How are they different and when in life do they occur Which type of effect has a sensitive or critical period o Organization Effects of Hormones Hormonal effects on the differentiation and development of the sex organs brain and behavior in early development Permanent Sensitive period o Activational Effect of a hormone that occurs in the fully developed organism beginning at time of puberty Feminization for females Females organization is Not hormone dependent but there are activation effects Masculinization and Defeminization for males Males are complicated and have a combination of organizational and activational What does the story of David Reimer also known as Brenda and Bruce tell us about the role of hormones in shaping the development of the brain and gender identity o Was born a male but was castrated and was raised a girl o The brain and body were in mismatch of the sex causing gender identification issues o Ambiguous genitalia as child because an androgen DHT is necessary for external characteristic development Often raised as girls Which hormone is responsible for sexual interest and behavior in males Females Is this an organizational or activational effect Does more of this hormone lead to more sexual behavior o Females Testosterone activates sexual behavior Activational Effect o Males Testosterone activates sexual behavior Activational Effect o For both sexes testosterone levels influence sexual interest and behavior o Adult androgens are permissive to sexual behavior More does not equal better Organizational effects other genes and experiences etc Individual differences still apply What is the role of the peptide hormones oxytocin and vasopressin in social bonding and monogamy What is the role of the reward system o Peptide Hormones Activate the reward system ventral tegmental area Leads to dopamine release in presence of that special someone Both ventral tegmental area and nucleus accumbens show greater activation to partner than unfamiliar if oxytocin given first o Oxytocin o Vasopressin In females promotes social monogamy In males promotes social monogamy What do females with congenital adrenal hyperplasia CAH tell us about the role of androgens to produce sex differences in the brain and behavior o Adrenal dysfunction leads to under production of cortisol and over production of sex steroids o Females with CAH are exposed to high levels of androgens during early development Girls with CAH showed preference in boys toys over girls toys Is the sex difference in the SDN an example of an organizational or activational effect Which developmental process leads to sex differences in the size of the SDN Is there a human correlate of the SDN o SDN Organizational effect Due to steroid hormones acting to prevent developmental apoptosis INAH 3 thought to be human analog to rodent SDN POA Are all sex differences in the brain related to reproduction What are some other examples Are sex differences in cognitive abilities associated with organizational or activational hormones o Majority of sex differences occur in the brain regions primarily related to o Others in brain regions related to reproductive and other behaviors reproductive behavior Hypothalamus spinal cord nuclei