Flashcards in Reproduction system Deck (74):
What does the reproductive system involves?
Production, storage, nourishment and release of gametes
What is gametes?
Haploid, specialised sex cells
What is the process that produce female and male gametes?
what is gonads?
Sexual organs that produce and store gametes
What is the female gametes? What is the male gametes?
Ova & Spermatozoa
What is the female gonads? What is the male gonads?
Ovary & Testis
What is fertilization?
A process of gametes being released from the gonads to enable fusion of the spermatozoon with the ovum.
This results in the formation of a zygote, which can then develop into an embryo
What is zygote?
Diploid, fusion of spermatozoon and ovum
Will develop into an embryo
What is embryo?
A developed embryo
The gonads also work as ________ ______
What is testis
Male gonad, site of spermatozoa production
Where is the site of spermatozoa maturation
What does scrotum do?
Suspend the testis (decrease the temp)
What is the carriage from epididymis to urethra?
vans deferens (ductus deferens)
What contributes to produce seminal fluid?
prostate glands, Cowper's glands, seminal vesicles
What is penis's role?
carriage out of the body
In the testis, spermatozoa are generated in the ________ _____
Spermatozoa are matured in _______ prior to _________
Seminiferous tubules contain spermatozoa at different development stages T/F
The development of spermatozoa is called___________
Spermatogenesis starts at _______, take ___ days to complete the process
Puberty, ~ 70 days
The average male produce ______ sperm per day
at least 150 million
Sperm is _____ times smaller than eggs
sperm is 0.04 mm long, 0.004mm wide
Name the ___ steps in spermatogenesis
[spermatogenesis] Type A spermatogonia (2N) (mitosis)
> Type B spermatogonia (2N)
> Primary spermatocytes (2N) (meiosis I)
> Secondary spermatocytes (1N) (meiosis I)
> Spermatides (early & late) (1N) (meiosis II)
> [Spermiogenesis] > Spermatozoa (1N)
Which cells provide nourishment to spermatozoa?
Name different parts of a mature spermatozoon
Head - [Head]
Middle piece >
Principle piece > [Tail]
End piece >
Describe Spermatozoon structure
Head - nucleus (Haploid) / acrosome
Middle section - long central filament/ many mitochondria
Tail - long central filament/ motile
Draw and name the male urinogenital system
scrotum/ epididymis/ vans deferous (ductus deferous)/ Cowman's glands/seminal vesicle/prostate gland/ penis/ testis
Draw and name the female urinogenital system
Fallopian tube/ board ligament/ vagina/ vulva/ uterine corpus / uterine cervix / ovary / uterus
Function of Uterine cervix
Selective protective barrier
Function of uterus
implantation & gestation
Which part of the female urinogenital system responsible for hormone product ? What other role it is responsible for?
Ovary, ovum production
Function of fallopian tube
transport and fertilisation
Name different regions of the fallopian tube
Fimbria/ infundibulum / Ampulla/ Isthmus/ Interstitial part
What is oogenesis?
The production of ova
Describe the development of oogenesis
~ The germinal epithelium outside the ovaries contain primordial germ cells, OOGONIA, in utero.
~ Some of the oogonia move deep into the ovary and develop into primary oocytes
~ Primary oocytes surrounded by follicle cells to become the primordial follicles ( ~400,000) but there's no further development before puberty
~ (the 1st stage of meiosis is halted)
What is the 2nd step of spermatogensis?
Diploid / Haploid?
Type B spermatogonia (Diploid)
What is primary oocytes?
The primordial germ cells (oogonia) moved into the ovary
what is oogonia ? What will it developed to?
The primordial germ cells produced by the germinal cells on the ovary.
They move deep into ovary and become primary oocytes
What is primordial follicle?
What stage is it at?
A primary oocyte surrounded by follicle cells.
Before puberty (1st stage of meiosis is halted)
Describe stages of oogenesis
Before Birth -
Oogonium (2N) > (mitosis) > many oogonia (2N) > primary oocyte (2N) (1st stage of meiosis I suspended)
After Birth -
(Re-start meiosis I) Secondary oocyte (1N) (and first polar body (1N)) > Ovulation of secondary oocyte > * If fertilisation occur, with sperm, meiosis II of secondary oocyte completed and develop into ovum and second polar body
* Meiosis II of first polar body may or may not occur
What happen to the polar bodies?
They will degenerate
Describe menstrual cycle
Multiple primordial follicles are recruited during the menstrual cycle. BUT only one reach maturity by developing and expanding into primary follicles and then into secondary follicles
What is the follicle called with meiosis I is completed and ready to go into meiosis II?
When is meiosis I completed?
What does it form?
Just before ovulation, matured primary oocyte are completed meiosis I and divided into 2 haploid: first polar body and secondary oocyte
What happen in ovulation?
The ovum (secondary oocyte surrounded by several layer of cells) is being released from the ovarian surface
Second meiotic division of the second oocyte doesn't take place unless....
The ovum is penetrated by a spermatozoon
What is a corpus luteum ?
Structure formed by ruptured follicles filled with blood after the ovulation
The corpus luteum breaks down and formed _______
The endocrine regulation of the ovaries, uterus, testes are affected by __________
Hypothalamus and pituitary gland
How does the hypothalamus gland regulate the male gonad?
produce gonadotropin releasing hormone (GnRH) > act on the anterior pituitary gland > cause the production and releasing of Luteinising hormone (LH), follicles- stimulating hormone (FSH) and prolactin
How does Luteinising Hormone affect male gonad?
It stimulates the Leydig cells to produce testosterone
How does follicle- stimulating hormone affect male gonad?
It makes sertoli cells respond to the testosterone
How does prolactin affect male gonad?
Stimulates the Leydig cells and add the effects of LH. It also increase the uptake of testosterone by prostate (needed to maintain prostatic secretion)
How does the hypothalamus gland regulate the female gonad?
produce gonadotropin releasing hormone > act on the anterior pituitary gland > to produce and release the Luteinising hormone (LH) and follicle- stimulating hormone (FSH)
How does follicle- stimulating hormone affect female gonad?
Stimulate the maturation of the primordial follicles so they can produce oestrogen
How does oestrogen affect female gonad?
When oestrogen level peaks, it feedback and stimulate a surge of Luteinising hormone secretion.
How does Luteinising hormone affect female gonad?
Stimulate the follicle cells to synthesis progesterone > follicle ruptures and the ovum is released (viable for 12- 24 hrs)
Corpus luteum produces ______ & _________ (Hormones)
Oestrogen & posgesterone
Describe the passage of spermatozoon from testis to oviduct
Spermatozoa is released from epididymus
> Chemical changes activates sperm to become motile
> Muscular activity in tube walls move them into vas deferens
> Seminal fluid is added to form semen
> Alkaline seminal fluid protect sperm from the acidic environment of vagina
> Spermatozoa move to the oviduct
> Undergo capacitation in order to fertilise the ovum, which involve the loss of glycoprotein from the spermatozoa surface and changes in motility
Describe the movement of spermatozoa in female urinogenital system
Vagina > cervix > uterus> oviduct
Fertilisation enables .....
~ Restoration of the DIPLOID number of chromosomes reduced during meiosis
~ Transmission of genes from both parents to offspring
When spermatozoon encounters an ovum, it must undergo which process ?
What is capacitation?
Spermatozoa lose their glycoprotein from the spermatozoa surfaces and change in motility, in order to fertilise with the ovum
What is Acrosome reaction?
The acrosome swelling, caused by the glycoprotein on the surface of the ovum
How does the "leaky" acrosome acts on the ovum?
It releases hyaluronidase and acts on the hyaluronic acid, which holds together the cell coating of the secondary oocytes
What is hyaluronic acid?
Need to break down by ?
It holds the cell coating of the secondary oocytes.
Hyaluronidase that released by the spermatozoa acrosome
Describe the process when a spermatozoon encounter an ovum
Spermatozoon releases hyaluronidase to act on the hyaluronic acid on the coating of oocyte
> the head can penetrate the oocyte
> the tails crease to move and remains outside
> the head of spermatozoon fuse with the oocyte and produce the diploid zygote
What happen after spermatozoon fuse with the oocyte ?
Zygote is produced and move along the fallopian tube to uterus
> Several additional development stages occurs during the journey, such as cleavage within the conceptus, ~ 16 cells
> Then implantation take place ~ 10 days after the ovulation and the placenta begins to form
> (Embryo is embedded until 8 weeks)
Roles of placenta
~ provide nutrition
~ gas exchanges
~ waste removal
~ Endocrine and immune support for the foetus
~ Produce human chorionic gonadotropin (hCG)
Stages of pregnancy
- organ formation of organs and limb buds
- sex is determined
- bony parts of skeleton begins to form (as cartilage)
- foetal movements can be felt by the mother
Circulatory and respiratory systems mature in preparation of breathing
What happen during parturition?
- During parturition, the cervix dilates to allow passage for foetus
- Uterine contractions propel the foetus through the birth canal
Which glands will release which hormones to be involved in parturition?
Oxytocin - posterior pituitary gland
Prostaglandins - uterus