Fertility and Conception: Principles Flashcards
When does sperm production in males begin? When does it end?
It begins at puberty and continues throughout a man’s life
What happens to spermatids at spermiogenesis?
They become polarised, allowing them to become mature spermatozoa
What is found inside the head of the sperm?
Condensed nuclear material
What surrounds the head of the sperm?
The acrosome
What is the function of the acrosome of the sperm?
Contains enzymes which help the sperm to penetrate the oocyte once they are released
What is found at the opposite end of the sperm to the head?
The tail, which elongates to form a flagellum
What organelle is found in abundance in the tail of the sperm? What is its function?
Mitochondria - to provide energy for movement
Spermatozoa are ejaculated alongside what? What is the purpose of this?
Seminal fluid - it neutralises the acidity of the vagina to allow the sperm to survive
Mature spermatozoa are released into where?
The seminiferous tubules
After mature sperm have been released into the seminiferous tubules, what happens to them?
They are transported in testicular fluid to the epididymis where they become motile and get stored
What produces testicular fluid?
Sertoli cells
During ejaculation, where do spermatozoa pass through?
The vas deferens and prostatic urethra
Spermatozoa combine with what at the prostatic urethra?
Seminal fluid (to form semen)
Seminal fluid is produced by what?
Seminal vesicles, prostate gland and bulbourethral glands
Only sperm which have passed through where are capable of fertilisation?
Epididymis
What are the 4 stages of sexual intercourse?
Excitement, plateau, orgasm, resolution
For how long after ejaculation into the vagina can sperm fertilise an egg?
Up to 5 days
Once sperm enter the female reproductive tract, where must they travel through before they reach the oocyte?
Cervical canal, uterus and fallopian tubes
What are used to neurtralise the acidic pH of the vagina and allow sperm to survive?
Cervical mucus and seminal fluid
The passage of sperm through the female reproductive tract is aided by what?
Uterine contractions which draw the sperm up the cervical canal
Once sperm reach the cumulus oophorus of the oocyte, what happens?
Their acrosome releases lytic enzymes that break up the cumulus cells and allow penetration of the zona pellucida
The first sperm that reaches the oocyte does what?
Fuses with it and releases its nuclear material into the cytoplasm
Nuclear material from a sperm being inserted into the oocyte has what effect?
Triggers the release of cortical granules in the oocyte cell membrane to make the membrane tough and impermeable to any more sperm
