Sexual Reprodiction In Humans🍆 Flashcards
What is the scrotum?
- Contains the testes
* Hang outside - cooler
What are the testes?
Contain the seminiferous tubules where spermatogenesis occurs
What is the epididymis?
Where the spermatozoa mature
What is the vas deferens?
Connects the epididymis to the urethra
What is the seminal vesicle?
Produces a secretion that aids the mobility of the spermatozoa and nourishes the sperm
What is the prostate gland?
Produces a secretion that neutralises the alkali of the urine and helps protect sperm from acidic secretions in the female body
What is the urethra?
Tube that carries urine and spermatozoa out the body
What is the penis?
Intromittent organ used to insert spermatozoa into the reproductive system of the female
What does the fluid from the accessory glands do?
- Maintains sperm mobility
- Provides nutrients
- Alkaline to neutralise acidity of urine in urethra and vagina
What is the ovary?
Oogenesis occurs here
What is the oviduct/fallopian tube?
- Site of fertilisation, where a spermatozoon fuses with an oocyte
- At fertilisation, a zygote is formed, which then moves down the oviduct towards the uterus
What is the uterus?
Embryo implants in the endometrium and then continues to develop in the uterus
What is the endometrium?
- Mucous membrane that lines the uterus
* Thickens during menstrual cycle in preparation for possible implantation of an embryo
What is the cervix?
Narrow passage forming the lower end of the uterus
What is the vagina?
During sexual intercourse, spermatozoa are deposited at the top of the vagina
What are the gametes?
- Haploid cells
- Contain half the full, diploid number of chromosomes
- Contains one chromosome from each homologous pair
What is gametogenesis?
Production of gametes
Where does spermatogenesis occur?
In the seminiferous tubules of the testes
What are spermatozoa?
Plural of spermatozoon (sperm)
Spermatogenesis process
•Germinal epithelial (2n) cells undergo mitosis to form spermatogonia (2n)
•Spermatogonia undergo mitosis form primary spermatocytes (2n)
•Primary spermatocytes undergo meiosis 1 to form haploid secondary spermatocytes (n)
-these complete meiosis 2 to form spermatids (n)
•Spermatids mature to form sperm (differentiation)
What is differentiation?
Development of specialised structures within the cell
Describe the sperm head
Contains a haploid nucleus
What is the acrosome of the sperm?
Releases enzymes that digest the zona pellucida in the acrosome reaction
Describe the body of the sperm
Contains mitochondria which release energy as ATP, e.g. used for flagellum
What is the function of the flagellum/tail?
Propels sperm using energy (ATP)
What is the function of Sertoli cells?
Nourishes and protects the sperm
What is the function of interstitial cells (cells of Leydig)?
Found in testes and secrete testosterone
What is the function of testosterone?
- Hormone involves in stimulating the process of spermatogenesis
- Induces male secondary sexual characteristics
How do spermatozoa move into the epididymis?
By peristalsis and the action of the cilia
Where does oogenesis produce oocytes?
In the ovaries