Lecture 38 - Coitus, fertilisation, and contraception Flashcards
Definitions of monarch
The onset of menstrual cycles
Definition of menopause
The cessation of menstrual cycles (usually in a woman’s 50s)
GnRH from the hypothalamus directly regulates the secretion of …
LH and FSH
During oogenesis, at what point in meiosis II is the secondary oocyte suspend and what event causes the cell cycle to resume?
Metaphase II
Dertilisation causes the cell cycle to resume (fertilisation can also be called sperm penetration)
What happens to the oocyte if fertilisation does not occur?
Atresia (degeneration)
Coitus
From the latin ‘a meeting together, sexual union’
Sexual intercourse/copulation
Erect penis introduced into vagina (intromission)
Semen released into upper part of vagina (insemination) so that sperm can travel to appropriate site for fertilisation (ampulla of uterine tube)
It is all about ensuring that the male gamete can be transported up into the female reproductive tract
Intromission
Erect penis introduced into vagina
Stages of the male sexual act
Erection of penis - parasympathetic (allows for intromission)
Mucus secretion into urethra - an erection is associated with secretion of fluid from the bulbourethral glands (in the pelvic diaphragm) which provides lubrication for the urethra and also cleans out any residual urine that might be present and this is then followed by ejaculation
Ejaculation
Two phases (both sympathetic)
Emission
Expulsion
Resolution - penis becomes flaccid
And then there is a refectory period where another erection can not occur
Two phases of ejaculation
Ejaculation
Two phases (both sympathetic)
Emission
Expulsion
The erection of the penis is a ________ response
Parasympathetic
The ejaculation is a __________ response
Sympathetic (both phases are)
Corpus spongiosum
Structure through which the urethra runs
Runs the entire length of the penis and widens to form the glans penis
Corpus cavernosum
Runs from the root of the penis to just below the glans penis - there is two of them
Bulbocavernosus muscle (bulbospongiosus)
very important in the ejaculatory process
Covers the bulb of the penis
Fascia of the penis
The erectile tissues are surrounded by different layers of fascia
Fascia are important in restraining the erection
Superficial fascia
Outermost fascia
Tunica albuginea
Two of these - one around the spongiosum and one around cavernosum
The tunica albuginea around the corpus spongiosum (and therefore surround the urethra as it is inside this) is not as dense as the other tunica albuginea
Deep (Buck’s) fascia
Buck’s fascia, which covers the corpora cavernosa and corpus spongiosum and attaches posteriorly to the suspensory ligaments of the penis, allowing the erect penis to achieve a horizontal or greater angle.
Trabeculae
Connective tissue containing smooth muscle which is important for the constraining and allowing of the vasculature to the erectile tissues
Lacunae
Blood filled spaces that are part of the process of expanding and causing an erection