U4 Sexual reproduction in humans Flashcards
What parts to both male and females have?
- A pair of gametes- producing organs
- A system of ducts
- Structures of copulation
What is the process called which men produce sperm?
spermatogenesis
Where are the testes found?
Hanging in a sac external to the body called the scrotum
What does the prostate gland do?
Secretes a white milky fluid that neutralises the acidity of any trace of urine and helps protect the sperm from acidic secretions in the female body
What does the seminal vesicle do?
Secretes a thick, clear fluid that nourishes the sperm.
What do the testes do?
Produce sperm
What does the epididymis do?
Transports and stores the sperm
What does the vas deferens do?
Carry the sperm from the epididymis to the urethra where it leaves the body
What does the urethra do?
Where urine and sperm exit the male body
What does the ovary do?
Structures around 2.5cm long containing small sac like structures called follicles produces the egg
What do the Fallopian tubes do?
Passage for the egg and sperm to meet and for a fertilised egg to travel up to the uterus
What does the penis do?
Responsible for transferring sperm into the female during sexual intercourse
What is the function of the uterus?
Nourish the developing fetus prior to birth
What is the function of the Endometrium?
Layer of cells lining the uterus that is rich in blood vessels
What is the function of the cervix?
It’s a passage that allows fluids to flow in and out of the uterus
What is the function of the vagina?
Lined with smooth muscles and epithelium that secretes mucus. It receives the sperm and a passage exit for the body
What is spermatogenesis?
The production and development of sperm cells
Where does spermatogenesis take place?
It takes place in the seminiferous tubules
What two types of cells do the seminiferous tubules contain?
- Germ cells-which undergo the two divisions of meiosis to form spermatozoa
- Sertoli cells which act as nurse cells enduring that the germ cells have adequate nourishment
What are the stages of Spermatogenesis?
- Germinal epithelium cells are diploid (2n). They divide by mitosis to make diploid spermatagonia and more Germinal epithelium cells
- Spermatogonia divide many times by mitosis and enlarge, making diploid primary spermatocytes and more spermatogonia.
- Primary spermatocytes undergo meiosis 1, making secondary spermatocytes.
- Secondary spermatocytes undergo meiosis ll making haploid spermatids.
- Spermatids mature into spermatozoa or sperm
How is spermatozoa production regulated?
Leading cells (interstitial cells) regulate spermatazoa via sec hormones (testosterone in the presence of luteinizing hormone) These leydig cells are found between the seminiferous tubules and the testes.
Where does Oogenesis take place?
In the ovaries
Where does the development of oocytes take place?
It’s situated in the outer region of the ovary
What happens to the oocytes at puberty?
A regular cycle starts to take place regulated by hormones. FHS (follicle stimulating hormone) stimulates the cells around the follicle to multiple.