Repro Flashcards
Where is GnRH released from?
Hypothalamus
What cells does GnRH act on and what hormone do they secrete?
Sertoli cells (FSH)
Leydig cells (LH)
What is the positive and negative feedback hormone on Sertoli cells (FSH)?
Activin +
Inhibin -
What are negative feedback hormones for GnRH?
Estradiol
Testosterone
Where are spermatozoa produced?
The testis
Where are spermatozoa matured?
Head and body of the epididymis
Where are spermatozoa stored?
Tail of the epididymis
What is the definition of spermatogenesis?
Process by which male gamete cells develop into spermatozoa
What are the 3 stages of spermatogenesis?
Spermatocytogensis
Spermatidogenesis
Spermiogenesis
What are the layers of the seminiferous tubule?
Spermatogonia -> Spermocytes ->Spermatids ->Spermatozoa
What is the “factory” of the testis?
Seminiferous tubules
What is the most immature spermatogenic sperm type?
Spermatogonia
What things can Spermatogonia do?
->Replicate (mitosis) to replenish level of Spermatogonia
->Replicate (mitosis) to form next stage of spermatogensis (primary spermatocytes)
What stage does the formation of the head, neck, middle piece, principle piece, and tail happen. Also loss of cytoplasm.
Spermiogenesis
What does the Golgi apparatus turn into?
Acrosomal vesicle and granule
What are the 4 phases within the spermiogenesis?
Golgi phase
Cap phase
Acrosomal phase
Maturation phase
What animal has the shortest spermatogenesis time?
Horse
Where are leydig and Sertoli cells found?
The testicles
What’s the result of meiosis?
A cell that is diploid to a cell that is haploid
What is the result of mitosis?
A cell that is diploid to a cell that is also diploid
What happens in the cap phase of spermatogenesis?
Acrosome begins to spread out over the spermatid nucleus
What happens during the Golgi phase of spermatogenesis?
Golgi apparatus turns into the acrosome
What happens during the acrosomal phase of spermatogenesis?
Middle piece develops and cytoplasm starts to shrink
What happens during the maturation phase of spermatogenesis?
Almost all cytoplasm is lost, mitochondria migrate to middle piece
Which cells in the female secrete LH?
Theca cells
What cells in the female secrete FSH?
Granulosome cells
What is the first phase of a follicle in a female?
Primordial follicle
What is the last phase before ovulation in a female?
Graafian follicle
What are the 3 phases of oogenesis?
Fetal
Prepubertal
Puberty
What occurs in fetal oogenesis development?
Sex cords break down
MITOSIS of oogonia to form pool of germ cells for the rest of her life
Most oogonia ARREST in first meiotic division
What is a primary oocyte?
The arrested oocyte in the ovary
What are follicular cells?
Follicular cells are the cells that form around an oocyte (occurs during fetal oogenesis)
At what point do you refer to something as a follicle?
When an oocyte is surrounded by follicular cells
What is an oocyte?
Single cell derived from a germ cell
What is a follicle?
Structure with oocyte AND supporting cells
What is atresia?
Atresia is the death/loss of follicular structure and oocytes
What occurs during prepubertal oogenesis?
Really only atresia and resting occurs here
What happens during the post pubertal oogenesis?
Secondary oocyte is formed (completion of the first meiotic division)
What are the 3 possible outcomes for a oocyte during post pubertal oogenesis?
Ovulation
Atresia
Fertilization
What occurs after the fertilization is the post pubertal oogenesis?
The second meiotic division! (First occurred after puberty) Also more polar bodies are formed
What region determines gonadal development?
SRY (sex determining region Y)
What moves from the placenta (allantois) to the genital ridge during sexual differentiation?
Primordial germ cells to the genital ridge through the yolk sac
What are the two sets of primordia that a fetus contains?
Mesonephric ducts (Wolffian)
Paramesonephric ducts (Mullerian)
Which duct fully develops in fetuses that are developing testicles?
Mesonephric ducts (Wolffian ducts)
Which duct will fully develop in fetuses that will develop ovaries?
Paramesonephric duct (Müllerian duct)
What determines the development of Mesonephric vs Paramesonephric ducts?
HORMONES
Presence of testosterone and anti mullerian hormone atrophies Müllerian duct
What is the exocrine part of the testis?
The seminiferous tubules
What are sertoli cell’s (sustentacular cells) two jobs?
1) Forms blood/testis barrier
2) Endocrine function (inhibin)
Where are Sertoli cells located?
Within the seminiferous tubules along the apical barrier (large nucleus)
Where are myoid cells located?
In connective tissue outside of seminiferous tubules
What do myoid cells do?
Moves spermatozoa through tubules
Where are leading cells and what do they do?
Where: In connective tissue outside of seminiferous tubule
What: Produce testosterone
What is the connective tissue through the testis called?
Tunica albuginea
What is the collection area of the seminiferous tubules in the center of the testis?
Rete testis
What does the Mesonephric duct form?
Efferent ductules (ducts leaving testis)
Epididymis
Ductus deferens
Ampullae
What is the structure of the epididymis?
Ciliated pseudostratified columnar epithelium
What is the structure of the epididymis?
Tube with ciliated pseudostratified epithelium and large majority is smooth muscle
What are the 5 accessory sex glands? (SPABU)
Ampullae
Seminal vesicles
Prostate gland
Bulbourethral gland
Urethral glands
What are the “Big 4” sex glands? (SPAB)
Bulbourethral gland
Ampullae
Prostate gland
Seminal vesicles
Which 2 species have all 4 of the “big 4” sex glands?
Horses and Ruminants
Which accessory sex glands does a pig have?
Bulbourethral gland
Seminal vesicles
Prostate gland
What accessory sex glands does a dog have?
Just prostate!
What accessory sex glands does a cat have?
Prostate and Bulbourethral glands
What accessory sex gland do all major species have?
Prostate gland!
What is the ampullae?
Terminal portion of ductus deferens
What is the size of the prostate dependent on?
Hormones (testosterone)
So neutered animals have small to no prostate
What facilitates testicular decent?
Gubernaculum testis
What do the cloacal folds develop into?
Penile urethra and scrotum
What fills with blood to cause an erection?
Cavernous tissue (corpus spongiosum)
What are the 2 types of penises amongst species variation?
Fibrous penis: Boar and ruminant
Vascular penis: Carnivores and horses
What are the two erectile tissues in the vascular penis?
Corpus cavernosa penis (2 outside urethral area)
Corpus spongiousum (surrounds urethra)
What is the preputial covering of the penis called?
Glans of the penis
Where are oocytes found in the ovary?
In the cortex
What is the difference in a mare’s ovary?
Structure is reversed where follicles are matured in the medulla rather than the cortex
Presence of an ovarian fossa where the oocyte is released from (looks a little like a kidney)
What is developed in the primary follicle that isn’t developed in the primordial follicle?
Zona pellucida
What’s the histological difference between the primary and secondary follicle?
The secondary follicle develops an antrum
What cells proliferate on the secondary follicles?
Theca cells accumulate around the outside of the granulosa cells
What are the two layers of Theca cells?
Theca interna and Theca external
What are specialized structures around oocyte of tertiary (Graafian) follicles?
Corona radiata
Cumulus Oophorus
What is the structure that remains immediately after ovulation?
Corpus hemorrhagicum
“Blood Body”
What is the job of the corpus luteum?
Hormone production (progesterone)
Is retained if pregnant
Is regressed if pregnancy does not occur
What remains if the corpus luteum (yellow body) is regressed?
Corpus albicans
What are the 5 stages of the estrus cycle?
Anestrus
Proestrus
Estrus
Metaestrus
Diestrus
What are the 2 primary functions of the uterine tube?
Transport ova
Site of fertilization
What are the 4 structures derived from the Paramesonephric duct?
Uterine tube
Uterus
Cervix
Anterior portion of vagina
What are the 3 regions of the uterine tube?
Isthmus (proximal and narrow)
Ampulla (middle and medium sized)
Infundibulum and folds (distal and large lumen with lots of folds)
What are the 3 layers of the uterus?
Endometrium
Myometrium
Perimetrium
What are the 4 layers of the vaginal epithelium?
Mucosa
Lamina propria
Muscularis
Adventitia
What does the crania vagina have instead of adventitia?
Serosa
Is the formation of the posterior vagina hormone dependent or independent?
Independent
What occurs during anestrus?
Quiescent ovary
What occurs during proestrus?
Rising estrogen, follicular development
What occurs during estrus?
Max estrogen, ovulation
What occurs during diestrus?
Estrogen and progesterone, CL forms
What happens during diestrus?
Progesterone, CL mature
What is the structure of the posterior vagina during estrus?
Increased thickness with keratinized epithelial cells
What forms into the clitoris?
Genital tubercle
What forms into the major labia?
Genital swellings
What is different in the avian female reproductive tract?
Only the left ovary and oviduct are retained in the adult (in contrast to both testicles present in the male)
What type of gland is the mammary gland?
Modified apocrine gland
What is the passage of milk through the mammary gland?
Interlobular duct
Lobular duct
Lobar duct
Gland sinus
