BIO 1620 EXAM 2

Sexual Reproduction
Click the card to flip 👆
1 / 154
Terms in this set (154)
Sexual Reproduction
fusion of haploid gametes (sperm & egg) to form diploid zygote
asexual reproduction
creation of offspring without fusion of gametes (produce clone)
budding
invertebrates only; from outgrowths
fission
sea anenme, starfish; parent separates into two
parthenogensis
reproducing without a male--evolution for survival species
diploid
46 chromosomes
haploid
23 chromosomes
what creates diversity in sexual reproduction?
crossing over (it mixes male and female chromosomes)
semelparity
reproduces once in a lifetime and then dies (ex: salmon)
iteroparity
2+ reproductive periods (ex: humans)
external fertilizationThe process by which the female lays eggs and the male fertilizes them once they are outside of the female. A moist habitat is always required for external fertilization to allow sperm to swim to the egg and to prevent the gametes from drying outinternal fertilizationoccurs inside of the animal... is an adaption to help the sperm reach the egg in a dry environmentInternal fertilization is typically associated with production of ____ gametes but the survival of a _____ fraction of zygotesfewer; higherpharomonesChemicals released by an individual that affects the behavior of another individual (used in internal fertilization)reproductive axisIntegration of the hypothalamus, ant. pituitary, and gonad to control reproductive hormones.Male GonadstestesTestessite of sperm production and also makes testosteroneEpididymissack attached to testes; site of sperm storage and final activationVas DeferensTube that carries sperm from the testes to the urethra.Accessory glands (of male reproduction)add fluid and other substances to create semen. (water, nutrients, buffers, sperm activators, mucous).Examples of male accessory glandsseminal vesicles, prostate gland, bulbourethral glandMale urethracommon duct for urine and semen to leave the bodyPenisthe organ used for introducing sperm to the female reproductive tractmale gametogenesismeiosis 1:secondary spermatocyte → meiosis II:spermatids → mature spermcomponents of spermhead, neck, midpiece, flagella (has mitochondria, is basically a fancy chromosome with a motor)hormonal control of testes -> testosteronehypothalamus, GnRH, anterior pituitary, LH, leydig cells, testosterone, spermatogenesis OR negative feedback loop to create more testosteronehormonal control of testes -> inhibinhypothalamus, anterior pituitary, FSH, Sertoli cells, inhibin and negative feedback loop or spermatogenesisinhibin only acts on the _____anterior pituitarytestosterone acts on the _____ and the _____anterior pituitary and hypothalamusFemale Gonadsovariesovariessite of egg production and maturation... makes estrogen and progesteronefallopian tubes (oviduct)transport eggs from ovaries to uterus, site of fertilizationUterussite where fertilized egg implants to form fetusCervixmuscular, lower portion of uterusVaginaconnects uterus to outside of body and functions as birth canalHow do female and male gametogenesis differ?the number of gametes produced and WHEN they're producedhow much sperm is produced in one heartbeat?~1,000 spermWhen are female eggs produced?Before the female is bornHow many eggs is a female born with?~1,000,000How many eggs does a female have at puberty?300,000How many eggs will be ovulated in a females reproductive lifetime?300-400 eggsFemale gametogenesisBefore birth: Oogonium --> primary oocyte Childhood to puberty: primary oocyte arrested in prophase 1 of meiosis 1 Monthly from puberty to menopause: Primary oocyte --> meiosis I --> secondary oocyte + first polar body --> ovulation --> secondary oocyte arrest in metaphase 2 of meiosis 2 --> meiosis 2 completed when fertilizationOvarian Cycle(Follicular phase) 1. formation of primary ooytes, 2. puberty= follicle growth, 3. follicle matures, 4. expelled through ovulation, (Luteal phase) 5. corpus luteum, 6. if not fertilized the corpus luteum degeneratesWhere is estradiol produced?in ovaries by follicle throughout developmentwhere is progesterone produced?in ovaries after ovulation (by corpus luteum)What type of feedback loop is estradiol?can switch between negative and positivefemale steroid hormones (2)estrogen and progesterin (slow acting)female peptide hormones (2)inhibin & activin (faster acting)menstruationbreaking down of the uterine lining (takes 7 days)As the follicle matures, estradiol ________.risesluteinizing hormone surgewhen estradiol is in a positive feedback loop and LH increases, thus causing OVULATIONprogesterone drop will initiate.....menstruationmenstrual cycles in animals are called...estrous cyclesspontaneous ovulatorsovulate on a regular cycle without any external influences... ex: rats, mice, horse, pig, sheep, human, etcinduced ovulatorsovulate after sexual contact... ex: rabbits, cats, ferret, deer, etccircadian ovulationoccurs before the start of the active period, seasonal (ex: sheep can only reproduce during certain seasons)capacitationfinal maturation of sperm occurs within female reproductive tractHow is sperm guided to the ovaries?progesteronecortical reactionenzymes prevent any other sperm from binding to the eggOocytes carry which of the sex chromosomes?one X chromosomeSperm can carry either anX or Y chromosomesex determination comes from thespermformation of a human zygote1. ovulation, 2. fertilization, 3. cleavage begins, 4. cleavage continues, 5. implantation of blastocystvasectomyligation of vas deferens; sperm is still created but absorbed by bodybirth controlreleases estrogen and progesterone, no ovulationabstinenceno sexcortus interruptuspulling outtubal ligationblocking the fallopian tubes to prevent fertilization from occurring. oocyte occurs but wont travel down tubesspermicideschemically destroy sperm by creating a highly acidic environment in the uterusa vasectomy stops fertilization at what stageafter the primary sperm and oocytecombo birth control stops fertilization at what stageafter the primary sperm and oocyteabstinence stops fertilization at what stagesperm transport and oocyte development/ovulationcondoms stop fertilization at what stagesperm transport and oocyte development/ovulationcortus interruptus stops fertilization at what stageAfter blastocyst formation, the embryo implants into the ________.endometriumcopper iud (paraguard)prevents sperm to join egghormonal iudcan stop ovulation, makes cervical lining thicker, so sperm cannot get to egginfertility preconceptionneuroendocrine, pituitary disorders, anti-sperm antibodiesneuroendocrine (kallman's syndrome)no progression through puberty and inability to smellpituitary disorders : infertilitycannot create FSH, LHanti-sperm antibodiesbody produces antibodies that fight off spermpost conception types of infertilityimplantation and chromosomal abnormalitiesimplantation infertilityuterine lining not sufficient to support a fetuschromosomal abnormalities (infertility)something is different than normal in the chromosomes, thus making it not a viabale pregnancyas many as _____% of pregnancies are lost before they are detected50%infertility affects men and womenequallycomidtricks body into ovulatingintrauterine inseminationsperm are placed directly into the uterusin vitro fertilization (IVF)egg and sperm cells are combined outside the body in a laboratory dish (in vitro) to facilitate fertilizationintracytoplasmic sperm injection (ICSI)injection of sperm into an oocyteCytoplasmic TransferInjecting cytoplasm from a donor egg into the cytoplasm of a recipient egg. This method would be used for someone who has "fragmented" cytoplasm and habitual miscarriage.AneuploidyAbnormal number of chromosomes.abnormal number of chromosomes usually occurs duringmeiosisabnormal number of chromosomes can causemiscarriage or abnormalitiesTriploidy2 sperm fertilizing one egg or one sperm fertilizing an egg that already has 2 copies of each chromosometrisomy 21 (1:800)Down syndrome- cognitive delays, weak muscle tone, heart defect, digestive abnormalities, thyroid problems, mental issues (attention, OCD, autism)Trisomy 18 (Edwards Syndrome)most die before birth or within first month 5-10% live to first birthday 1:5000--(increases with mothers age)Trisomy 13 (Patau Syndrome)severe intellectual disability, heart defects, brain and spinal cord Most die within first days or weeks of life 1:16,000Aneuploidy of Sex ChromosomesXXX or YYY and have normal featuresKlinefelter Syndrome (XXY)-develops as a male -small testes, female features , tall, language impairmentTurner Syndrome (X0)monosomy... individuals are sterileturtles- coldmaleturtles- warmfemalesgenetic sex determinationchromosomes determine sex of offspringenvironmental sex determinationthe environment determines sex of offspringhow many chromosomes does an egg have?23how many chromosomes does a sperm have?23how many chromosomes does a zygote have?46 (diploid)Life cycle of a frog1.fertilization 2.cleavage 3.gastrulation 4.organogenesis 5.morphogenesis 6.adultwhere does conception occur?fallopian tubes/ oviductacrosomal reactiontriggered when the sperm meets the egg, the acrosome at the tip of the sperm releases hydrolytic enzymes that digest material surrounding the eggcortical reactioncreation of fertilization envelope; preventing other sperm from getting inWhat prevents polyspermy?cortical reactionpolyspermyfertilization by more than one spermcortical reaction occurs right after...acrosomal reactionfertilization envelope is correlated with...CA2+how long after sperm attachment until the envelope around the egg is developed?one minutezona pellucidathick barrier between outside world and oocyte (in mammals)cell divison begins _____-_____ hours after sperm binding12-36cleavagerapid cell divison without growth, but increasing number of cellsblastulaball of cells w fluid filled centeridentical twinsmonozygotic-1 sperm, 1 egg, share placentafraternal twinsdizygotic- 2 sperm, 2 eggs, separate placentacleavage in a frog embryohas 2 hemispheres-animal and vegetalcleavage furrowcrack thingafter the cleavage furrow in a frog embryo they have a ________ distributionasymmetricvegetal poleyolk, stored nutrients, extra embryonic membranesanimal poleCell division of the embryoblastocoelthe fluid-filled cavity of a blastula that contains nutrientspregnancy tests detectHCG (human chorionic gonadotropin)highest amount of HCG is between ___-____ weeks8-16hcg is released bythe placenta (9 days after ferilization)Gastrulationorganization of cells into different layersdiploblastonly 2 layers formed in gastrulation... ex: hydratriploblastan animal that develops from three germ layersWhen does gastrulation start?week 3a diploblasts blastopore will form...an open ended digestive systema protosomes blastopore will form...the mouthIn deuterostomes, the blastopore becomes the ________.anus... with mouth on the other sideectodermoutermost layer; nervous and sensory systems... pituitary gland and adrenal medulla. ALSO jaws and teethmesodermmiddle layer; skeletal and muscular system, circulatory and lymphatic system, excretory and reproductive systems (EXCEPT GERM CELLS), dermis of skin, and adrenal cortexendoderminnermost layer; epithelial linings... especially of digestive tract, thymus, thyroid, and parathyroid glandsprimitive streakA groove on the surface of an early avian embryo along the future long axis of the body. HELPS produce brain and spinal cordtrophoblastouter layer of blastocystinner cell massThe mass of cells in the blastocyst that ultimately give rise to the hypoblast and epiblastepiblast(elongated cells) the outermost layer of an embryo before it differentiates into ectoderm and mesoderm.hypoblastforms barriernames of extraembryonic membranesamnion, chorion, yolk sac, allantoisamnionMembrane that encloses the embryo in protective amniotic fluid (w nutrients)chorionoutermost layer of the fetal membrane... gas exchangeyolk sacThe yolk sac is an extra-embryonic membrane that provides food for the embryo.the yolk sac is most developed in what kind of species?ones that are egg-grownallantoisThe allantois is an extra-embryonic membrane that is involved in gas exchange and stores uric acid.amniotesreptiles, birds, mammals