| Term | Definition |
|---|
| Sequestered early in development, PGCs appear early in the epiblast and migrate through the yolk sac and other extra-embryonic tissues to the gonadal ridge (prior to gonadal differentiation) | primordial germ cell (PGC) |
| Expressed by the extra-embryonic tissue, BMP4 activates the PGCs in the epiblast (correlation: present; necessary: mutant mice do not form PGCs; sufficient: adding BMP4 rescues migration in vitro) | BMP4 and PGCs |
| PGCs migrate through the blood | PGCs and birds |
| somehow involved in PGC pathway (correlation: germ cells, neural crest cells, and RBCs all share the same ligand (stem cell factor) and transmembrane receptor (c-kit tyrosine kinase); necessary: mutations in ligand/receptor affect fertility, pigmentation, and blood cell development; sufficient: adding SCF in vitro stimulates cell division and may decrease cell death) | c-kit and PGCs |
| Errors in germ cell migration become invasive germ cell tumors that are typically positive for c-kit mutations | c-kit and cancer |
| Homeodomain TFs that are correlated with a totipotent germ cell state | Oct4 and nanog |
| correlated with an increase in mutation rate with paternal age leading to increased rates of achondroplasia, Apert's syndrome, and schizophrenia | spermatogonial stem cells and excessive mitosis |
| spatial and temporal | sperm develop in a _____ and a _____ sequence within the seminiferous tubules in close association with somatic Sertoli cells |
| spermatogonia --> primary spermatocytes --> meiosis I --> secondary spermatocytes --> meiosis II --> spermatids (haploid) | steps of spermatogenesis |
| sperm cells way of remaining connected in order to share diffusible X-chromosome gene products | cytoplasmic bridges |
| timing of meiosis, polar bodies, cytoplasmic bridges, maintenance signals | key differences between spermatogenesis and oogenesis |
| diploid cell creates haploid progenitor, both needed for fertilzation | key similarities between spermatogenesis and oogenesis |
| produce androgen-binding protein for testosterone and MIS (Mullerian Inhibiting Substance)/AMH (Anti-Mullerian Hormone). Defect leads to many disorders of male fertility | Sertoli cells |
| produce testosterone, less closely associated with spermatogenesis | Leydig cells |
| morphogenesis and differentiation of the spermatid into the spermatozoa | spermiogenesis |
| acrosome (contains enzymes that exocytose for acrosomal reaction), haploid nucleus (with nuclear proteins and protamines, tightly condensed and functionally inactive), midpiece with mitochondria, axoneme (flagella with dyenin ATPase motor) | key features of mature human spermatozoa |
| nucleus condenses, chromatin remodeled with histones replaced by transition proteins then protamines (rich in Cys and Arg). Capacitation and chemotaxis occur in the female reproductive tract. | spermiogenesis events |
| primary oocytes enter meiosis at birth (vs. puberty) and remain in arrested prophase I for decades. After ovulation, arrested again in metaphase II (only completes MII after fertilization). | timing differences in oogenesis |
| None found | stem properties of oogenesis? |
| peak of 7 million oocytes during fetal life, down to 2 million at birth, 300,000 at puberty. At 35, oocytes increase in atresia rate. | oogenesis numbers |
| ovaries degenerate into streak gonads in the absence of follicles (insufficient estrogen to maintain ovary) | streak gonads |
| association with survival of oocytes (correlation: present in oocytes and granulosa cells during early ovarian development; necessary: blocked c-kit receptor causes follicles to undergo atresia). | c-kit and oogenesis |
| control growth of the oocyte, transcription, maturation, and meiotic arrest (OMI-oocyte maturation inhibitor) | granulosa cell (cumulus oophorus) |
| oocytes and granulosa (follicle) cells, made up of 4 glycoproteins including ZP2 and ZP3. Surrounds the germ cell | what makes the zona pellucida (egg coat)? |
| from 10 mito/PGC to 100,000 mito/mature oocyte; may have implications in the accumulation of mitoDNA mutations | mitochondria changes during oogenesis |
| heterogeneity of mitochondrial genomes that lead to stochastic partitioning of mito into daughter cells | heteroplasmy |
| invasive trophoblast growths with bipaternal genomes and no fetus (absent maternal genome) | hyatidiform moles |
| 5 days prior to ovulation and on the day of ovulation | peak probability of conception |
| ampulla of uterine tube | site of fertilization |
| poorly-characterized process by which sperm gain motility in the uterine tube | capacitation |
| process by which sperm meet the egg follicle in the ampulla | chemotaxis |
| (1) chemotaxis, (2) binding of sperm to ZP, (3) ZP-induced acrosome reaction, (4) penetration, (5) fusion of sperm and egg membranes, (6) release of sperm-specific isoform of phospholipase c which begins Ca++ cascade, (7) egg microfilaments draw paternal nucleus into egg and protamines replaced by histones, (8) onset of protein synthesis in zygote, (9) egg cytoskeletal microtubules center the 2 pronuclei, (10) first cleavage | steps of fertilization (10) |
| (1) sperm and egg binding, (2) acrosome reaction, (3) species specificity, (4) slow block to polyspermy, (5) surround re-embryo during pre-implantation development (hatching from ZP precedes implantation) | roles of egg coat (5) |
| example of cell signaling via free intracellular Ca++, the major event in sperm-egg fusion which involves an isoform of IP3 (phospholipase C) | fertilization and Ca++ |
| no single form of contraception is sufficient for all stages of reproductive life span | contraception |
| lower birth weight and potentially higher incidence of congenital abnormalities | concerns with IVF (2) |
| low bith weight is related to increased risk of CVD, hypertension, stroke, and diabetes in adulthood | Barker hypothesis |
| helps stimulate ovulation | GnRH agonist |
| can occur at a range of stages, the later the stage, the more shared extra-embyonic membranes | monozygotic twinning |
| influenced by parity, age, diet | dizygotic twinning rates |
| twinning after the point of gastrulation | conjoined twins |
| fusion of twins prior to gastrulation, chimeric woman with different haplotype from sons, and a hermaphrodite chimera resulting from ART lab | natural mammalian chimeras |
| fusion of two mice embryos at 8-cell stage (each ZP removed) which is then implanted in a foster mother (embryo has 4 parents). Taught us about lineage, commonality of signals and receptors between cells of different embryonic origin, create animal disease models, reflect the ability of the pre-embryo to regulate, cooperate, ad build an individual from two or more origins, and used to reevaluate the boundaries of genetic individuality (regulative abilities). | experimental mammalian chimeras |
| involves a single pass transmembrane protein called syncytin. fusion between cells are rare events | placenta-trophoblast fusion |
| week-long process with detectable rise in syncytiotrophoblast-generated hCG in maternal serum (day 8) and urine (day 10) | implantation |
| stimulates the corpus luteum to produce progesterone to maintain pregnancy through week 8, high sustained levels indicator of ectopic pregnancy, spontaneous abortion, or hyatidiform moles | hCG |
| transient embryonic structures with global significance of the axis and pattern of the embryo, can be tested by transplantation and waiting for an inductive response in the host tissue and your target | organizer |
| primitive streak, AVE (anterior visceral endoderm), notochord, node | examples of organizers |
| extra embryonic tissue that is necessary and sufficient (Oct 2C -/- mutants do not produce neural ecto) for induction of forebrain structures | AVE (anterior visceral endoderm) |
| key roles played by nodal (BMP/TGF family signaling molecule, upstream) and pitx-2 (transcription factors). Pitx-2 expressed in the left lateral plate mesoderm during and after the time of nodal expression; pitx-2 mutants have defective asymmetry; pitx-2 mice can sometimes be rescued by expression of the pitx-2 transgene) | left-right asymmetry |
| primitive streak present posteriorly while neurulation is occurring anteriorly | gastrulation and neurulation |
| oocyte signals to follicle | signals these follicle cells to proliferate, differentiate, expand, and produce steroids. |
Combine with other sets
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