Insect Reproduction

babijovo's version from 2018-03-21 05:21

Section 1

Question Answer
sex determinationx-o & haploid dipoid system, x:A ratio
parthenogenesisProduction of eggs without the participation of sperm. Offspring may be diploid (2N) or haploid (N) depending on the species.
advantages of asexual repno mate needed, more progeny
disadvantages of asexualno genetic variation to adapt to environment
paired testes may fuzeconsist of many sperm tubes that produce sperm cells
vas deferensduct from each testis to carry sperm cells for storage in the seminal vesicles
accessory glands may add fluids or a covering to the sperm cells
sperm exit the body through the ejaculatory duct aedeagus
Sperm either is transferredspermatophore or naked
Apterygota transfer spermexternally
Pterygotes transfer spermdirectly and internally to female
Hemocoelic (traumatic) inseminationpuncture female
ovary consists of variable number of ovariloles,blind - end tubes where eggs form
3 of ovarioles4-8 ovarioles on each side
Yolkproteins, lipids, carbohydrates & makes up most of egg
egg is enclosed inchorion (shell) & vitelline membrane
chorion shell secreted byby follicle cells
vitelline membranesecreted by oocyte
air exchange occurs via small holes (perforations in the chorion)microopyles
After maturation, eggs move intolateral oviduct then median oviduct then genital chamber, then
spermatheca stores sperm
Accessory glandsopen to genital chamber, secrete various substances
Eggs are fertilized when sperm enter microopyles
# of eggs1-2000
Oviparity (most common)egg is produced, fertilized, then oviposited outside the female.
Ovoviviparityeggs develop normally and are fertilized, but are retained in females reproductive tract until they hatch. Female deposits larvae or nymphs (not an egg)
Viviparityeggs begin to develop, but lack enough yolk for complete development & often lack a chorion - embryos retained inside mother, receive nourishment after development has begun.
Polyembryonyone egg is laid in the host, clones itself & can produce from a few to 1,500 offspring. Found in some parasitic wasps
Wolbachiakill males
Feminization wolbachiainfected males turn into females or sterile pseudofemales
Cytoplasmic incompatibility wolbachiainfected males cannot reproduce with uninfected females or different strains
sperm competitionSperm precedence (first male to mate) or Reduce effectiveness of subsequent matings

Section 2

Question Answer
The egg stage beginas soon as the female deposits the mature egg
eclosionemergence from the egg
instarEach developmental stage of an insect s life cycle
stadiumThe interval of time passed in an instar is termed
ontogenythe developmental history of that organism from egg to adult
all pterygotes undergometamorphosis
hemimetabolousimcomplete metamorphosis
exopterygoteexternal wing development (hemimetabulous)
“resting or reorganization” stagepupal
Endopterygoteswings not visible during larval stages
imaginal discswings developing inside body
butterflies & moths c4 - 6 molts
The molt into the pupal instar is called pupation
exarate pupalappendages free,no cacoon, beetles wasps
obtect pupalappendages adhere to body, some moths cacoons, butterflies moths
coarctatepupa enclosed in next to last larval instar skin,the puparium, flies
voltinismnumber of generations per year
way to measure insects livesvoltinism
apolysisepidermis separates from the cuticle of the previous stage .
Three major types of hormones control molting and metamorphosisprothoracicotropic hormones(PTTH, ETH, EH eclosion hormone), ecdysteroids, juvenile hormone
Hypodermis starts secreting a new epicuticle (outer layer)epicuticle (outer layer)
new procuticle formed old isdigested, reapsorbed, used to make new procuticle
Physiological timeday - degrees; D °

Section 3

Question Answer
Systematicsthe science dealing with the diversity of organisms and of any and all relationships among them
Allopatric SpeciationGeographic separation
Sympatric Speciationprocess through which new species evolve from a single ancestral species while inhabiting the same geographic region
Adaptationtrait that increases fitness
Developmental Biologyprocesses by which an organism grows from zygote to adult.
Homeotic genes(HOX)are a group of genes that control the body plan of an embryo along the head - tail axis.
Homeotic proteinsdetermine the type of segment structures that will form. segmental identity
Homeotic (HOX genes) locationsBithorax complex (BX - C), Antennapedia complex (ANT - C)