exam 3 Flashcards
where does capacitation occur?
oviduct
which type of sperm loss is when leukocytes attack sperm cells?
phagocytosis
what type of sperm loss is when sperm flows back out the vagina?
retrograde loss
what species is not a short copulator?
stallion
what species is an intermediate copulator?
stallion
which species is a sustained copulator?
boar
when do females exhibit reproductive behavior?
limited to estrus
when do males exhibit repro behavior?
anytime after puberty
what is the most effective way to manipulate male repro behavior?
new female and new environment
do sperm have catabolic (break down) or anabolic (re-build) metabolism?
catabolic
T/F: males have memory when it comes to copulation
true
what receptors do leydig cells have?
LH
what receptors do sertoli cells have?
FSH and T
which phase of spermatogenesis does not have cell division?
differentiation
what process occurs in the basal department of the seminiferous tubules?
mitosis
what process occurs in the adluminal department of the seminiferous tubules?
meiosis
what process occurs in the luminal department of the seminiferous tubules?
spermiation
which phase of differentiation is when the golgi apparatus takes proteins and creates vesicles?
golgi phase
which phase of differentiation is when granules form across al vesicles flatten and make a “cap” over the nucleus of sperm?
cap phase
which phase of differentiation is when the sperm head takes shape and the nucleus begins to elongate?
acrosomal phase
which phase of differentiation is when the entire spermatazoon is covered in the plasma membrane and excess cytoplasm turns into the cytoplasmic droplet?
maturation phase
where are leydig cells located in the seminiferous tubules?
interstitial space
where are sertoli cells located in the seminiferous tubules?
tubular compartment
Thermoregulation is key for successful spermatogenesis, if the temp of the testes becomes too hot or too cold, the spermatazoa lose the ability to fertilize an oocyte. Explain all of the methods used to maintain proper temp (include temp that the testes need to be).
Spermatogenesis = development of male gamete. Provide a detailed description of each developmental stage and where they would be located in the seminiferous tubule.
- proliferation phase: type a spermatogonia develop into intermediate spermatogonia, and those develop into type b spermatogonia; spermatocytogenesis/mitosis is happening; up to 75% apoptosis
- meiosis phase:
- meiosis I: increasing genetic diversity via DNA replication and crossover
- meiosis II: produces 1N spermatids (haploid)
- differentiation phase: changing shape of spermatid to spermatozoa; no cell divisions; morphological change; 4 subphases
- golgi phase: acrosomic vesicle forms around head of sperm
- cap phase: acrosomic vesicle spreads over nucleus
- acrosomal phase: elongation of head (circle to almond shape)
- maturation phase: final assembly; entire spermatozoon is covered with plasma membrane; mitochondria spiral around the tail; proximal droplet will translocate down the tail to a distal droplet
The primary purpose of mating behavior is copulation, thus bringing male and female gametes together to ensure propagation of the species. Does the male/female initiate courtship-specific behaviors? why?
females because they are confined to estrus and will only show reproductive behavior during that time
Once spermatazoa undergo capacitation and reach maximum fertility, the next step in fertilization is the acrosome reaction. Know all the steps of fertilization after the acrosome reaction.
- cortical reaction: cortical granules exocytose to stimulate Zona and vitalline block (prevents polyspermy)
- sperm nucleus de condenses
- fertilization stimulates ooctye to enter meiosis II to reach final haploid state
- male and female pronucleus = syngamy
why are the testes housed outside the body?
spermatogenesis occurs at temps 4-6 degrees less than internal body temperature (37-31 degrees C)
what factors contribute to thermoregulation? how?
1st: scrotum
- sweat glands in scrotal skin
- location
- tunica dartos muscle (sustained contractions)
2nd: spermatic cord
- pampiniform plexus (counter current heat exchange)
- cremaster muscle (contracts to raise/lower the testes)(can not sustain contractions)
what are the two parts of the parenchyma and what do they contain?
- interstitial compartment: leydig cells
- tubular compartment: sertoli cells and seminiferous tubules
what is the CT core of the testes that house the rate tubules?
mediastinum
what is the functional component of the testes?
seminiferous tubules
what cells produce T and where are they found?
leydig cells— found in the interstitial compartment of the parenchyma
where are sertoli cells found and what is their function?
tubular compartment of the parenchyma, provide support to developing germ cells
what are the functions of the testes?
- produce sperm/spermatogenesis (via sertoli cells)
- transport sperm out of the testes
- 3 ways: tunica albuginea, myopic cells, and fluid absorption - produce T (via leydig cells)
what are the functions of T in males?
- stimulates secondary sex characteristics
- maintains libido
- maintains function of male repro tract, penis, and muscles for ejaculation
what are the components of the spermatic cord? what is its function?
- cremaster muscle: raises and lowers to regulate temp and protect the testes (fight or flight)
- pampiniform plexus: blood supply to the testes, counter current heat exchange
- vas deferens: transports sperm into the body, connects the cauda epididymis to the ampulla
what is counter-current heat exchange?
causes the cooling of arterial blood supply, warms blood as it leaves the testes, exchanging of the entropy of heat into the blood
what factors does each portion of the epididymis add to sperm?
- caput: add fertilization factors
- corpus: add decapacitation factors (army gear)
- cauda: add motility factors
where is sperm matured?
epididymis
where is sperm stored?
caudal epididymis
what epithelium layer makes up the epididymis and what function does it serve?
pseudostratified columnar epithelium that secretes and absorbs fluid vehicle
what is the chemical composition of of seminal plasma?
- energy sources: fructose is necessary for sperm activity and function
- buffers: bicarbonate maintain pH (bc there are rapid changes in the pH of the uterus)
- prostaglandins: stimulate muscle contractions for sperm movement
- glycoproteins: protects genetic material and retards capacitation