Term
| What are advantages of sexual reproduction? |
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Definition
1) recombination mixture of paternal and maternal genes
2) selection in mate choice |
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Term
| What is the dominated by time phase in meiosis? |
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Definition
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Term
| Describe chromosome position and composition in prophase I? |
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Definition
| Chromosomes have replicated and consist of two tightly joined sister chromatids |
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Term
| When grossing over occurs? |
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Definition
| Chiasma can be observed in metaphase I. |
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Term
| What are the phases of cell cycle and their typical duration? |
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Definition
| G0, in which cells are resting or quiescent; G0 (days, weeks, years). G1, in which cells undergo RNA and protein synthesis necessary for entry in to S-phase; G1 (4 - 10 h). S-phase, in which cells undergo DNA replication; S (7 - 12 h). G2, in which cells undergo RNA and protein synthesis in preparation for mitosis;G2 (3 - 5 h). M-phase, in which cells undergo mitosis and cytokinesis. M (0.5 – 2 h). |
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Term
| When sister chromatids are separated during meiosis? |
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Definition
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Term
| Where Sertoli cells originate from? |
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Definition
| Epithelium of seminiferous tubules |
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Term
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Definition
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Term
| Which cells sperm origanate from? |
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Definition
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Term
| How recognize spermatogonium? |
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Definition
Ovoid nucleus that contains chromatin associated with the nuclear membrane
adjacent to the outer basement membrane of the sex cords
stem cell capable of regenerating itself as well as producing a new cell type |
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Term
| What is the genetic content of spermatocyte I, II and spermatide? |
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Definition
| Spermatocite I - 4n Spermatocite II - 2n Spermatide - n |
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Term
| How much does it takes to produce a sperm in human? |
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Definition
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Term
| Outline the process of mammalian sperm construction |
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Definition
| 1)Construction of the acrosomal vesicle from the Golgi apparatus 2) formation of cap covers nucleus 3) Nucleus rotates so cap face basal membrane 4)flagellum is beginning to form from the centriole 5)the nucleus flattens and condenses, the remaining cytoplasm is jettisoned 6)the mitochondria form a ring around the base of the flagellum |
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Term
| Which phase oocyte is waiting for fertilization in? |
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Definition
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Term
| Where we can see “lampbrush” appearance of chromosomes? |
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Definition
| In oocyte in prophase I, when the synthesis of proteins and RNA occure |
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Term
| When is first polar body produced? |
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Definition
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Term
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Definition
| Pre-implantation diagnostic, the cells are taken from embrio (cleavage state) or from polar body for analysis |
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Term
| When implantation of the embrio occurs? In what stage? |
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Definition
| Blastocyst is implanted on 5-6 day |
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Term
| By what the histons are replaced in sperm? |
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Definition
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Term
| When compactization occurs? Cavitation? |
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Definition
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Term
| What is the acrosomal reaction? |
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Definition
| It is a reaction between acrosome of the sperm and zona pellucida of the oocyte. |
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Term
| What zona pelucida composed of? |
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Definition
| Of three glycoproteins, ZP1,ZP2,ZP3 |
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Term
| Which glycoprotein in zona pellucida is essential for fertilization? |
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Definition
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Term
| How oocyte is protected from double fertilization? |
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Definition
| 1) cortical reaction: after sperm invades egg, cortical granules are released and they dissolve zona pelucida,so other sperm could not go though 2)Ca wave: increase concentratuion of Ca in the egg's cytoplasm depolarizes it. |
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Term
| What provides longterm blockage of polyspermy? |
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Definition
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Term
| Which tissues arise from ectoderm? |
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Definition
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Term
| Which tissues arise from endoderm? |
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Definition
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Term
| Which tissues arise from mesoderm? |
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Definition
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Term
| What causes Angelman-Syndrom? |
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Definition
| In a normal individual, the maternal allele in the chromosome 15 is expressed and the paternal allele is specifically silenced in the developing brain. If the maternal contribution is lost or mutated (by deletion,uniparental disomy, translocation, or single gene mutation), the result is Angelman syndrome. |
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Term
| How many genes are imprinted? |
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Definition
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