Midterm Review Flashcards
Name one important event that occurs at Metaphase 2 in the development of fish eggs?
Fertilization..
At which stage does meiosis stop to allow vitellogenesis to proceed?
Prophase 1
At Prophase 2 in the development of fish eggs the nuclear membrane of the egg disappears for a second time. What name is given to this event in the fish reproductive biology?
GVBD
When androgenesis is applied to fish in which males have heterozygous sex chromosones( XY) what is the sex chromosome composition of the resulting fry and what are the proportions of the resulting groups?
1/2 female XX
1/2 male YY
Thecal and granulosa cells form the wall of which feature of the fish ovary?
Follicle
In developing a triploid stock of fish, using shocking techniques, the timing of what critical stage of meiosis is determined?
Anaphase 2
What effect does estrogen have on the liver during fish gonad recrudescence?
Stimulates vitelligenin and lipid production in the liver
List 3 methods to remove eggs from maturing female fish to examine their stage of development?
- Hand stripping
- Surgically remove and suture
- Sacrifice and cut open
Or use the tube to suck eggs out
How would you identify the ovary of a fish displaying synchronous oogenesis?
oocyte at one stage of development
What hypothalamic hormone inhibits the secretion of gonadotropic hormone by a fish pituitary?
GTHRHIF- dopamine
Name a chemical that can be used to decrease or eliminate the negative feedback that estrogen has on a pituitary secretion of gonadotropic hormone?
Tamoxafin
What is the main environmental cueing mechanism which inhibits recrudescence in mature temperate freshwater and marine fish?
photoperiod
Why have tropical freshwater fish evolved to use changes in water quality as an important cur for ovulation?
Increase in nutrients and increase in productivity due to the rainy season
What hormone serves as a photoperiod transducer in the reproductive biology of fish?
melatonin
What two characteristics of photoperiod are most important in cueing recrudescence in fishes?
- direction of change
2. rate of change
List 2 reasons why LHRHa is the most likely reproductive hormone to succeed in inducing ovulation in difficult to spawn fish?
- It is not species specific
2. It stimulates the fishes own GTH to increase
Doperidone blocks the action of what hormone in fish reproduction, aiding ovulation?
Blocks dopamine
Name 2 substrates that can be used to make pellets for the long term administration of spawning induction hormones in fish?
- Coconut oil
2. Cellulose
What human hormone can be used to stimulate or mimic the gonadotropins of fish when inducing fish to spawn?
HCG
List 3 disadvantages of the use of sex steroids in producing MONOSEX stocks of fish?
- Low market appeal
- Must treat all production fry
- fry must be obtained less than days from hatch
What advantage does gynogenesis offer in developing lines of monosex female fish for masculinization with testosterone?
You will know all fry are female
Balon’s reproductive fish guilds are based on what 3 characteristics of fish reproduction?
- early development form and function
- preferred spawning ground and substrate
- adult reproductive behavior(spawning and incubation)
IN pelagic marine fish, which scatter eggs, what component of the egg determines the depth at which it incubates?
Lipid content
What purpose might a downwardly curved tail, in a fish larvae, serve?
forces the larvae to swim down to hide
