Chapter 10: Sexual And Reproductive Behaviors Flashcards
Sexual Dimorphic Behavior
Behavior that has different forms or that occurs with different probabilities or under different circumstances in males and females
Sex
Genetic or physiological characteristics of males and females
Gender
Refers to socially- influenced identity, roles, and/or behavior of individual as they pertain to male and female identities
Intersex
Variety of combos of biologically male and female characteristics, such as individual born with external female genitalia and internal male sex organs
Transgender
Gender identity that does not necessarily correspond to biological sex at birth
Gametes
Mature reproductive cell (sperm or ovum)
- Produced during cell division process called meiosis
- Produces cells that contain one set of each of pairs of chromosome
Genetic Sex
Determined by presence of XX or XY chromosome
- determined at time of fertilization
Sex Chromosomes
X and Y chromosomes, which determine an organism’s genetic sex
Exposure to sex hormones, […], is responsible for much of […]
Exposure to sex hormones, both before and after birth, is responsible for much of sexual dimorphism
3 categories of sex structures
Gonads
Internal sex organs
External genitalia
Gonads
- Testes and ovaries; first sex organs to develop
- Produce ova or sperms and secrete hormones
- Through 6th week of prenatal development, male and female fetuses are identical
- Both sexes have pair of identical undifferentiated gonads
SRY
Gene on Y chromosome whose product instructed undifferentiated fetal gonads to develop into testes
- absence of gene produces ovaries
Organizational Effect
Effect of hormone on tissue differentiation and development
- Permanent and persist throughout person’s life
Activational Effect
Effect of hormone that occurs in fully developed organism
- Occur later in life - May depend on organism’s prior exposure to organization of hormones
Wolffian System
Epididymis, vans deferents, seminal vesicles
- Testes secrete two types of hormones:
- Anti-Mullerian Hormone
- Androgen
Anti-Mullerian Hormone
Peptide secreted by fetal testes that inhibits development of
Mullerian system, which would otherwise become female internal sex organs
- Defeminizing Effect
Defeminizing Effect
Effect of hormone present early in development that reduces or prevents later development of anatomical or behavioral characteristics typical of females
Androgen
Male sex steroid hormone (testosterone and dihydrotestosterone)
- Masculinizing Effect
Masculinizing Effect
Effect of hormone present early in development that promotes later development of anatomical/ behavioral characteristics typical of males
Androgen Insecurity Syndrome
Condition caused by congenital lack of functioning androgen receptor
- In person with XY sex chromosomes, causes development of female with testes but no internal sex organs - Androgens don’t have Masculinizing effect - Anti-Mullerian hormone has defeminizing effect, preventing female internal sex organs from developing
Persistent Mullerian Duct Syndrome
Condition caused by congenital lack of anti-Mullerian hormone or receptors for this hormone
- In male, causes development of both male and female internal sex organs - Androgens have their masculinity effect, but defeminization does not occur
Turner Syndrome
Presence of only one sex chromosome (X chromosome)
- Lacks ovaries but otherwise normal female sex organs and genitalia
External Genitalia
Visible sex organs:
- Males: penis and scrotum - Females: labia, clitoris, and outer part of vagina
In presence of dihydrotestosterone, male external genitalia develops
- Female sex hormones are not required for female genitalia development - Development of person’s external genitalia is determined by presence/ absence of androgen
Primary Sex Characteristics
- Influences by organizational effects of hormones
- Present at birth; includes gonads, internal sex organs, and external genitalia
Secondary Sex Characteristics
- Influenced by activational effects of hormones
- Develop during puberty
- Puberty triggers hypothalamus to secrete gonadotropin-releasing hormones
Gonadotropin- releasing hormones (GnRH)
Hypothalamic hormone that stimulates anterior pituitary gland to secrete gonadotropic hormone
Gonadotropic Hormone
Hormone of anterior pituitary gland that has stimulating effects on cells of gonad
- Follicle-stimulating hormone (FSH) - Luteinizing hormone (LH)
Follicle-stimulating hormone (FSH)
Hormone of anterior pituitary gland that causes development of an ovarian follicular and maturation of ovum
Luteinizing Hormone (LH)
Hormone of anterior pituitary gland that causes ovulation and development of ovarian follicle into corpus luteum
Secretion of […] is under control of […]
Secretion of GnRH is under control of kisspeptin
Kisspeptin
Peptide produced by neurons in accurate nucleus of hypothalamus under control of leptin receptors
- essential odor initiation of puberty and maintenance of reproductive ability
Gonads secrete sex hormones
Estradiol
Estrogen
Estradiol
Principle estrogen of many mammals, including humans
Estrogen
Class of sex hormones that cause maturation of female genitalia, growth of breast tissue, and development of other physical features characteristics of females
Menstrual Cycle
Female reproductive cycle of most primates
- characterized by growth of lining of uterus, ovulation, development of corpus luteum, and menstruation
Estrous Cycle
Female reproductive cycle of mammals other than primates
Menstrual cycle begins with secretion of gonadotropins by […], which stimulates growth of […]
Anterior pituitary, ovarian follicles
Ovarian follicles
Cluster of epithelial cells surrounding an oocyte, which develops into ovum