Unit 3 Flashcards
Hormones
Chemicals that send signals to different parts of the body, either to or from the body to or from the brain. Required to produce Gender.
Steroid Hormone
Body -> Brain. Hydrophobic, thus bypasses the hydrophobic blood-brain barrier. In utero: causes physical differences btw genders (genitalia/musculoskeletal). Puberty: activates expression of sexual physiology and gamete formation. All steroid based on cholesterol.
Peptide Hormone
Brain -> Body. Hydrophilic. Not restricted by blood brain barrier. Produced by proteolysis from precursor proteins. IE vasopressin, oxytocin.
Proteolysis
Process by which peptides are produced by being broken off from larger “precursor” proteins. Can lead to multiples effects and reactions to stress (ACTH [stress] is cleaved off of POMC precursor, but so is enkephalin [pain relief]).
Anterior Pituitary
Contains endocrine cells controlled by cells in the hypothalamus. Hypothalamus cells release neurotransmitters into the blood to start up endocrine cells in AP (pituicytes) to release hormones into brain. Contains larger variety of cells and peptides than posterior.
Posterior Pituitary
Contains pre-synaptic terminals from cells in the hypothalamus. Offers a direct connection between the brain and body as peptides are directly released into the blood.
Pituitary Gland
Master gland. Controls release of peptide hormones into the bloodstream. Essentially is a portal system through which the brain interacts with the body chemically.
Hypothalamus
Site of synthesis of peptide hormones. Releases hormones into blood via terminals in the posterior pituitary.
Vasopressin
ADH (anti-diurectic hormone). Controls water retention. Stops bed-wetting. Influence sex behavior in males and maternal behavior in females.
Oxytocin
Controls uterine contractions during labor and milk letdown from breasts. Influence sex behavior in males and maternal behavior in females.
Corticotrophs
A pituicyte in the ant. pituitary. Synthesizes POMC (precursor protein), and thus secretes ACTH (stress) into the blood stream. Hormone release from the AP is stimulated by Thyrotropin (Corticotropin Releasing Thyroid Hormone) producing cells.
Gonadotrophs
A pituicyte in the ant. pituitary. Synthesizes and secretes Follical Stimulating Hormone (FSH) and Lutenizing Hormone (LH) into blood supply. Release from AP is stimulated by Gonadotropin Releasing Hormone (GnRH) cells in the hypthalamus.
Negative Feedback in the Pituitary Gland
Body must maintain homeostasis, thus some hormones have actions that prevent further production of the hormone. EG: HPA Axis: Hypothalamus releases CRH -> AP releasing ACTH -> Adrenal Cortex releasing cortisol -> cortisol inhibits CRH and ACTH release.
Genomic vs. Non-Genomic Effects of Steroid Hormone
Genomic: Passes through membrane onto a nuclear receptor on the nucleus where it activates the relevant genes (SLOW).
Non-Genomic: Lands on a membrane receptor which activates 2nd messengers (FAST).
Progesterone/Estradiol
Steroid Hormones responsible for female reproduction. High concentration in breasts, vagina, uterus, and assoc brain regions.
Testosterone
Steroid hormone with organization and activational role in male reproduction. High concentration in male genitalia, hair follices, muscle groups, and assoc. brain regions.
Cortisol
Steroid hormone related to stress in males and females.
Steroid Conversion
Aromatase turns testosterone carbon ring into estrogen by aromatization. Causes gynoclymastia
Reductase turns testosterone carbon into ditestosterone by adding a Carbon ring. Causes male baldness
Steroids and Gender
Men and women both have testosterone and estrogen (among others), just in different levels. Steroid responsiveness is determine by presence and concentration of receptor, not hormone.
Primary Sexual Characteristics
Determined by genotype in the developmental state of the primordial gonad. Y chromosome: gene for the testosterone-sensitive Testes Determination Factor, which signals formation of testes instead of ovaries. If no testosterone, no testes.
Secondary Sexual Characteristics
More visible expressions of gender. Determined by the presence or absence of estrogen/testosterone activity.
Castration
Produces a feminizing effect before puberty.
Testicular Feminization Syndrome
XY genotype but unresponsive to androgen, thus develops as the default female phenotype.
Homosexuality
No natural equivalent for exclusive homosexuality in animal kingdom, and no evolutionary pressures for non-reproductive behaviors. Early theory by LeVay: smaller hypothalamus. Debunked b/c subjects were HIV+.
Testosterone Levels
Rises rapidly after puberty, peaks around mid-20s, and slowly declines thereafter, dropping after 60. Link between blood testosterone, aging, and sex activity
Female Receptivity
Passive females accepts male sexual activity. Early theory of all sexuality.
Female Selectivity
Females are discriminate, only accepting advances from dominant males.
Female Proceptivity
Females are aggressive and actively seek sexual contact. Driven behavior: Alpha has sex -> overthrown by others -> new alpha having sex = Genetic Variability.
Female Menstrual Cycle
CONSULT DIAGRAMS
Estrus Sex Behavior
Sex only at certain times, usually peri-ovulatory. Males very interested at only this time, otherwise are hunting/foraging/etc. Largely in animals
Menstrual Sex Behavior
Sexual behavior throughout cycle with increased frequency and constant male attendance necessary. Leads to tribal groups as females cannot be left alone. Human behavior
Lutenizing-hormone Releasing Hormone
Produces sexual behavior in female mammals.
Fixed Action Patterns
Discrete stages of mating.
Ultimate Fixed Action Patterns: responsible for initiating causal event (attraction, arousal) [Lordosis: female arching of spine].
Proximate Fixed Action Patterns: direct cause and effect (copulation) [erection, intromission, ejaculation in males]
SEXY BRAIN STUFF
CONSULT OTHERS’ NOTES
Pharmacology
Study of the action of drugs on living organisms.
Neuropharmacology
Drug-induced changes in functioning of nerve cells.
Psychopharmacology
Drug-induced changes in behavior
Neuropsychopharmacology
Drug-induced changes in the function of select neurons that influence specific behaviors
Drug Action
Molecular changes produced by drug binding to target site or receptor
Drug Effects
Molecular changes that alter physiological/psychological function
Therapeutic Drug Effects
Drug/receptor interactions that produce the desired effect
Drug Side Effects
All non-desired drug effects varying from annoying to dangerous
Depressants
Produce general decrease in cognitive and behavior processes. Ex: marijuana, barbituates, benzos
Stimulants
Produce general increase in behavior and thought. Ex: nicotine, caffeine, amphetamines, cocaine