Insect Reproduction Flashcards
What are female gonads called?
Ovaries
What are male gonads called?
Testis
What portion of the reproductive organ originates from the mesoderm?
Paired gonads and ducts
What Portion of the reproductive organ is of ectodermal origin?
Everything under where the lateral ducts meet?
What structure receives the male adeagus?
Genital chamber/Bursa copulatrix
Where are Sperm stored in the female?
Spermatheca
What functions do the female accessory gland serve?
Provide nutrients to the eggs and cement-like secretions to protect it on the outside
What are the different parts of the ovarioles?
Germarium and Vittelarium
What occurs in the germarium?
Oogonia produce Oocytes
What can be found in the Vitellarium?
Nurse cells, vitellogenins, follicle cells, forming the chorion
When does meiosis occur for the egg?
After ovulation, fertilization or oviposition, not in ovariole
What are egg micropyles?
Tiny pores on a portion of the egg to let sperm through
What is the haploid gamete of the female called?
Ovum
Where does the egg go after fertilization?
Proceeds down the genital tract to be coated by accessory gland secretions
What are the mature testis made of?
Sperm tubules in membranous sac
What is spermiogenesis?
Production of haploid sperm in sperm tubes
What structure carries sperm from the testis to the ejaculatory duct?
Vas deferens
What aggregate forms can sperm take on?
Semen or Spermatophore
What are the functions of the male accessory glands?
Add fluids and additional coverings to protect spermatophores from desiccation and to allow semen to be liquid
What structure transfers sperm to the female?
Aedeagus
What are the different portions of the sperm tubes called?
Germarium, Zone 1 (growth), Zone 2 (Maturation, meiosis), Zone 3 (Transformation)
What is the function of the male germarium?
Production of spermatocytes by mitosis
What is the function of the zone of maturation?
meiosis, spermatocytes become spermatids
What is the function of the zone of transformation?
finished development of the gamete with a tail, creating spermatozoa.
How do sperm leave the sperm tubes?
In bundles
What two hormones can control the development of gametes?
Juvenile Hormone or Ecdysteroids
What is Oviparity?
Egg production and fertilization done interiorly, egg oviposition following fertilization but before hatching with sufficient yolk, waxy chorion to prevent desiccation, most common
What is Ovoviparity?
Eggs are fertilized interiorly and incubate in female reproductive tract, eggs hatch inside female or immediately following oviposition ready to eat
What is Pseudoplacental Viviparity?
Yolk deficient fertilized eggs provide additional nutrients to the eggs through placental-type feeding, no oral feeding
What is Hemocoelous viviparity?
Embryos develop freely in hemolymph of the female, embryos take up nutrients through osmosis, rare
What is adenotrophic viviparity?
Poorly developped juvenile hatches inside mother and feeds orally on accessory gland secretions, full grown larva deposited to immediately pupate
what is parthenogenesis?
Asexual reproduction where an unfertilized egg develops into an individual
What is Thelytoky?
A form of parthenogenesis that creates only female individuals
What is Arrhenotoky?
A form of parthenogenesis that creates only male individuals
What is Amphitoky/Deuterotoky?
A form of parthenogenesis that creates both male and female individuals
What is apomictic Parthenogenesis?
Production of diploid females through parthenogenesis, purely by mitosis
What is automictic parthenogenesis?
production of a diploid offspring, but meiosis does occur, haploid egg fuses with haploid polar body to create diploid individual
What is generative parthenogenesis?
Production of haploid individual offspring through parthenogenesis, usually male
What is haplodiploidy?
Sex determination mechanism in Hymenoptera and Thysanoptera by which ploidy determines sex
What is Paedogenesis?
A combination of parthenogenesis and viviparity by which offspring hatch inside the mother and the mother is usually eaten as a result
What is Hermaphroditism?
A reproductive strategy where individuals develop both male and female reproductive organs
What is Mating Behaviour?
All events involved inn the transfer of sperm from male to female
What are the three steps of Mating Behaviour?
Finding Mates, Copulation, Oviposition
How do insects find mates?
One sex must send out a signal that is received by the opposite sex
What forms of Visual Mate Finding are there?
Swarming, LEK Mating-System, Flight patterns, Colouration, Lighting systems of fireflies
What are characteristics of Swarms?
Male-dominated, effective for low-density populations, promote outbreeding
What are characteristics of LEK Mating-System?
Ariel and/or substrate-based aggregation, males hold certain territory, male-male aggression for the territory
What is the difference between LEK and Attraction to a common resource?
In LEK the two sexes do not meet on a productive resource for the female
What type of EMR can help distinguish butterfly patterns?
UV Light
What chemical do Fireflies use to light-up?
Oxidation of Luciferase, with ATP
How else can lighting up be used in insects?
Used to mimic mating calls, to attract prey, to deter predators
How do mosquitos use sound for mate finding?
Male mosquitos use the Johnston’s organ in their antennae to perceive the wing vibrations of female, able to detect readiness of female for copulation
What is Stridulation?
Rubbing of Stridulatory pegs against a file structure on their bodies creates a high-pitched call, typical of orthoptera
How do Cicadas Produce sound for mating?
Males have an abdominal tymbal, a ribbed-thing cuticular membrane that vibrates when distended by muscles, air-sac aids in the amplification of sound, species-specific
What is Drumming?
For insects that use sound for mating but don’t have structures to create a sound, they tap against substrates to create vibrations. Another example would be water striders on water
What is olfactory Mate Finding?
The use of volatile chemicals to attract mates i.e. pheromones, moths have species-specific chemicals that they use as pheromones
What kind of flight do moths engage in to find females?
Optomotor anemotaxis
What type of olfactory Chemical is used in Close-Range courtship?
Courtship pheromone
What are different forms of close-range courtship?
Tactile Stimulation, Dancing, Courtship Pheromones
What is Tactile Stimulation?
When mates find one another they engage in some form of touch to assess the fitness of the other individual
What insect is known for using dancing as part of their short-range courtship?
Fruit Flies and other diptera
What are the different structures used in Olfactory short-range courtship?
Coremata (extensible, scent-producing glands), androconia (Wing scales with glandular cells), Hair pencils (glandular hair-like Scales)
What is Courtship pheromone derived from?
Specific chemicals found in diet can’t be synthesized just from the body of the lepidoptera
What are the two methods of sperm transfer in insects? Which is more ancestral?
Spermatophore (more ancestral) and Internal Fertilization
Which order exhibits random deposition of spermatophore?
Collembola
What is the difference between direct and indirect sperm transfer?
Direct sperm transfer is where spermatophore or sperm is placed inside the female repro system via an intromittent organ. Indirect is where Spermatophore is placed in environment and female picks it up secondarily.
What are the parts of the aedeagus?
Phallobase, endophallus, flagellum
What are the different strategies of paternity assurance?
Prolonged Copulation, Post-Mating Guardian, Mating first with a newly emerged female, Removing sperm of previous male, Sperm Plugs, Fighting over Females, Sneaky Copulators, Gift Giving
What is a nuptial gift?
Resource offering to the female by the male to then have sex
What is a spermatophylax?
Sperm free portion of the spermatophore exreceted from the adaegus that serves as a nuptial gift containing nutrients and sodium.
What is sexual cannibalism?
A means by which the man is eaten by the woman after hes spread his seed.
How can sexual cannibalism lead to a sperm plug?
Some sand flies adaegus remains attached to within the female after they perish.
How can the male regulate the female fecundity?
Fecundity enhacing secretions from the accessory gland, Receptivity inhibiting subtances form the accessory glands and sperm plugs
What is a good example of indirect sperm transfer in flying insects?
Odonata that place the spermatophore on a secondary site for the female to uptake
How is site selection for oviposition chosen?
Genetically and learned from immature
What is an ootheca?
Casing surrounding the oviposition of many eggs produced by the accessory glands.
