Lecture 10: Sex Flashcards
gender
the characteristics and traits considered socio-culturally appropriate for men and women. the term ‘gender’ implies biological mechanisms
sexual orientation and gender identity
can be measured along a spectrum with characteristics traditionally considered more masculine or feminine
sex differences
there are both biological and sociocultural differences between genders
asexual reproduction
only requires a single parent
sexual reproduction
based on evolutionary theory, sexual reproduction must have an adaptive function. asexual reproduction would ensure the passage of harmful mutations, while sexual reproduction reduces this chance. sexual reproduction also gives rise to diversity and possibility that future generations will have an advantageous genetic combination
sex determining region of the Y chromosome (SRY)
a region on the Y chromosome that has the gene which codes for sex. the SRY is linked to a testes-determining factor (TDF), which allows male gonads to develop
female genitalia
the entire external female genitalia is called the vulva. first there is mons veneris, as area of fatty tissue with a triangle of pubic hair above it. from mons veneris, on either side of the vulva, extends to labia majora, separated by the pudendal cleft
labia minora
hairless flaps of skin that are located inside the labia majora and surround the opening of the vagina. the inside of the labia is called the vastibule and at the top, where the labia minora meet, is the clitoral hood
corpus cavernosum
the erectile tissue of the clitoral shaft consists of two corpus cavernosum, which are blood-gilled chambers
pacini’s blood cells
provides deep sensation and sensory vibration
urethral opening
the main function of the urethra is to allow urine to leave the bladder
perineum
the sensitive area between the vagina and the anus
hymen
the young girls vagina is “covered” by a membrane of the skin referred to as the hymen. the tearing of these membranes during sex has great significance in many cultures, indicating that the women is no longer a virgin
vagina
the tube that connects the uterus to the external genitalia. its function is to carry the male’s sperm to the uterus for fertilization, and it is also the route by which the offspring are taken to the outside world
three levels of the vagina
- internal mucosal layer: provides a larger surface area when extended due to the elastic fibers present and the network of blood vessels. it is transudate of these blood vessels, combined with cervical mucus, that provides vaginal fluid during sexual arousal
- intermediate muscularis layer: the muscle layer
- external adventitial layer: an elastic tissue that provides structural support and allows for expansion
cervix
at the top of the vagina there is the cervix. the cervix has an opening through which sperm can enter the uterine environment and menstrual fluid can leave the uterine environment
three layers of the uterus
- inner layer: the endometrium made of connective tissue
- middle layer: the myometrium made of smooth muscle
- outer layer: the perimetrium made of connective tissue
fallopian tube
at the top of the uterus is the fallopian tube which extends left and right. the fallopian tube delivers ova from the ovaries to the uterus. at the end of the fallopian tube is an area called the infundibulum, where fimbriae branch to catch released ova and direct them to the tube. it is the ampulla, middle part of the fallopian tube fertilization is most likely to occur
cilia
fill up the inside of the fallopian tube. hair like structures that facilitate the movement of the ovum along the tube
scrotum
contains the testicles that are visible beneath the surface of the skin
corpora cavernosa
responsible for most of the erection. around it is connective tissue and this is called tunica albuginea
corpus spongiosum
passes through the midline of the surface of the penis around the urethra
sex hormones
much of the adolescent behavior is attributed to sex hormones, which are made of cholesterol and fall into three categories
three categories of sex hormones
- androgens: such as testosterone and 5-alpha dihydrotestosterone (DHT). these are typical male sex hormones
- estrogens: such as estradiol. these are reproductive hormones
- progestins: such as progesterone. these are female sex hormones
both sexes posses androgens and estrogens, but at different concentrations
aromataste
an enzyme which helps convert testosterone into estradiol
5-alpha reductase
an enzyme that converts testosterone into DHT
conversions
- cholesterol > progesterone > testosterone
- testosterone > (aromatase) > estradiol
- testosterone > (5-alpha reductase) > DHT