Chapter 4 The Chromosome Theory of Inheritance 4-1
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Sections to study4.1 Chromosomes: The carriers of genes4.2Mitosis:Cell division thatpreserves chromosomenumber4.3 Meiosis: Cell division that halve chromosome number4.4Gametogenesis4.5Validation of the chromosome theory4-2
Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 4-2 Sections to study Sections to study 4.1 Chromosomes: The carriers of genes 4.1 Chromosomes: The carriers of genes 4.2 Mitosis: Cell division that preserves chromosome 4.2 Mitosis: Cell division that preserves chromosome number 4.3 Meiosis: Cell division that halve chromosome number 4.3 Meiosis: Cell division that halve chromosome number 4.4 Gametogenesis Gametogenesis 4.5 Validation of the chromosome theory 4.5 Validation of the chromosome theory
Chromosome4.1 Chromosomes:ChranChrcmatidNucleurTekomereThe carriers ofCentromeregenesTelomoreCellBase PairsNA(doubie helix
Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 4-3 4.1 Chromosomes: 4.1 Chromosomes: The carriers of The carriers of genes
1667-Anton van LeeuwenhoekSemen contains spermatozoa ("sperm animals")Hypothesized that sperm may enter egg to achieve fertilization1854-1874-confirmationoffertilization through union ofeggsand spermsObserved fertilization in frogsand sea urchins using microscopyThe nucleiare the only elementscontributed equallyby spermsand eggs.4-4
Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 4-4 1667 – Anton van Leeuwenhoek Anton van Leeuwenhoek Semen contains Semen contains spermatozoa spermatozoa (“sperm animals sperm animals”) Hypothesized that sperm may enter egg to achieve fertilization. Hypothesized that sperm may enter egg to achieve fertilization. 1854-1874 – confirmation of confirmation of fertilization through union of fertilization through union of eggs and sperms eggs and sperms Observed fertilization in frogs Observed fertilization in frogs and sea urchins using microscopy. and sea urchins using microscopy. The nuclei are the only elements The nuclei are the only elements contributed equally by sperms contributed equally by sperms and eggs. and eggs
Evidence that genes reside in chromosomes1880s-innovations in microscopy and stainingtechniques identified thread-like structures:chromosomes(coloredbodies")4-5Fig.4.8
Copyright © The McGraw-Hill Companies, Inc. Permission required to reproduce or display 4-5 Evidence that genes reside in chromosomes Evidence that genes reside in chromosomes 1880s – innovations in microscopy and staining innovations in microscopy and staining techniques identified thread techniques identified thread-like structures: like structures: chromosomes chromosomes (“colored bodies colored bodies”). Fig. 4.8