Cell Nucleus and Chromosomes: This series illustrates the various structures of nuclei and chromosomes, pictures of mitosis and polyploidy, living nuclei, shape of nuclei and function, giant chromosomes, polyploidy, fine structure of nuclei, chromosome structure, mitosis, individuality of chromosomes. - Typical animal cell, showing all details visible by light and electron microscope - Typical plant cell, showing all details visible by light and electron microscope - Nuclei of the alga Spirogyra and of an amoeba, live - Onion epidermis: position of nucleus in plant cell, live (phase contrast) - Onion epidermis: fixed and stained nucleus - Nuclear membrane of a plant cell, tetrazyclin-fluorescence - Simple animal cells in sec. of salamander liver showing nuclei, protoplasm, and cell walls - Nuclear equivalents in bacteria, acridinorange-fluorescence - Chromato- and centroplasm in blue-green algae (Oscillatoria), fluorescence - Metabolically active nucleus (interphase nucleus) of Vicia faba. Chromocentres, chromonemata, centromeres - Lampbrush chromosomes of diplotene stage in living egg cell of salamander (phase contrast) - Polytene giant chromosomes: nucleus from salivary gland of Chironomus larva, live - Sex chromosomes: spermatozoa without and with X-chromosomes from testis of a locust - Arrangement and shape of nuclei due to tissue functions: nuclei of connective tissue, chains of nuclei in skeletal muscles - Nuclear volume and size due to activity: epithelium of active and inactive thyroid gland - Nuclear shape in cancer cells not due to function - Polynucleate cells: giant cells of Langerhans and macrophages - Giant cell of a sarcoma - Syncytium, an undivided mass of protoplasm containing many nuclei - Position of nuclei in animal cells, classes of nuclear size - Polyploid nuclei: intestinal epithelium of an insect - Chromosomes during mitosis, squash preparation of Allium root tip DNA stained by Feulgen - Polyploid nuclei: polyploid chromosome sets of cultivated plants - Enlargement of nuclear surface: nucleus of a suctorian and giant nuclei in endocrine organs - Pigment cells in the skin - Motor nerve cell shows nucleus, nucleolus, Nissl’s granules, and nerve processes - Glandular epithelium, t.s. showing goblet cells - Fine structure of the nucleus: nuclear membrane, nuclear content, nucleoli, electron micrograph - Ditto: nuclear membrane and RNA exit, electron micrograph - Ditto: fibrillar structure of chromosomes, electron micrograph - Rearrangement of nuclei in spermatozoa, electron micrograph - Mitochondria in thin sec. of amphibian liver - Mitochondria in plant cells, high magnification detail - Mitochondria, diagram - Golgi apparatus in epithelial cells - Golgi apparatus in secretory cells, electron micrograph: endoplasmatic reticulum and dictyosomes - Golgi apparatus, diagram - Chloroplasts with grana from cells of Tradescantia, bright field - Ditto. fluorescence - Chloroplasts, electron micrograph, mesophyll cell: cell walls, vacuole, chloroplasts, grana of plastids - Ditto: chloroplast showing starch, grana and thylakoids - Ditto: chloroplast; highly magnified cut-out with details in grana, thylakoids, ribosomes - Chloroplasts, diagram - Amitosis (direct division), division of nucleus and cell body without appearance of chromosomes, t.s. of liver - Amitotic division of the nucleus of Amoeba proteus - Paramaecium in binary fission. Simple form of reproduction - Paramaecium in conjugation. A temporary union of two individuals during which nuclear material is exchanged - Paramaecium, common ciliate, anatomy, diagram - Amoeba proteus, habit, cyst, feeding, division, diagram - Cell division (mitosis) in animals, nine subsequent stages, diagram - Cell division (mitosis) in root tips of onion, eight subsequent stages, diagram - Mitosis: root tip of Allium cepa; all stages in one picture - Mitosis: root tip of Hyacinth; metabolically active nucleus and early prophase - Mitosis: root tip of Hyacinth; prophase and early metaphase - Mitosis: root tip of Hyacinth; equatorial plate and early anaphase - Mitosis: root tip of Hyacinth; telophase and reconstruction - Mitosis: chromatid bridges with fragment during anaphase - Centrioles, centrospheres, spindle fibres: meiosis of an egg cell - Mitosis: fine structure of spindle apparatus and chromosomes, electron micrograph - Comparison of haploid and diploid chromosome sets of various plants and animals, diagram - Human chromosomes during metaphase (equatorial plate) - Normal karyotype with GAG banding pattern - Individuality of chromosomes I. Male and female pronucleus of Ascaris, chromosomes of pronuclei - Individuality of chromosomes II. First cleavage spindle, first cleavage. - Follicles in mammalian ovary: Young primary follicles with flat epithelial cells t.s. - Ditto: Older primary follicle with higher epithelial cells t.s. - Ditto: Secondary follicle with stratified epithelium t.s. - Ditto: Young Graafian follicle, showing formation of a vacuole l.s. - Ditto: Older Graafian follicle, showing large vacuole, discus proligerus and oocyte l.s. - Ditto: Mature oocyte with membrana pellucida and corona radiata t.s. - Sea-urchin development: Uncleaved egg, before fertilization. Large nucleus - Ditto: Uncleaved egg, after fertilization. A fertilization membrane becomes visible - Ditto: Two-cell stage. Formation of two equal blastomeres after the first cleavage - Ditto: Four-cell stage, polar view.

Chromosomes and Genes: Nuclei and chromosomes are conspicuous structures of cells. The part they play in cellular activities, their function and importance in heredity and cell division, as well as their molecular-biological aspects are treated in part II and III of this atlas. - Structure of chromosome: diagram of a chromosome seen under the light microscope - Giant chromosomes of Chironomus, diagram - Structure and activity of chromosomes: loop complex of a chromosomal puff in polytene chromosome of Chironomus. - Chromosomes: giant chromosomes of Chironomus, DNA-RNA-staining with orceine and light green - Inheritance of two linked genes in Drosophila: cross, backcross, linkage groups - Gene exchange between two corresponding linkage groups of Drosophila, chromosomal interpretation - Oogenesis, spermatogenesis, fertilization and cleavage in animals, diagram - Gene locations (loci). Map of loci on chromosomes of Drosophila - Meiosis: t.s. of mammalian testis. Spermatogonia, meiosis of spermatocytes I and II, spermatids, spermatozoa - Meiosis: squash preparation of mammalian testis, orceine stain - Maturation divisions in mammals, diagram - Maturation divisions in plants (Lilium), 18 subsequent stages, diagrams - Meiosis and mitosis in microspore cells of Lilium: microspore mother cells, resting stage - Ditto: leptotene stage, chromosome threads with chromomeres - Ditto: zygotene stage, pairing of homologous chromosomes. - Ditto: pachytene stage. Termination of pairing: homologous partners are in close contact forming bivalents - Ditto: diplotene stage. Concentration and spiralization of pairs, chiasmata - Ditto: diakinesis stage. Maximal shortening of chromosomes, nucleolus dissolves - Ditto: metaphase of the first (heterotypic) division, formation of the equatorial plate - Ditto: equatorial plate, surface view showing the duplicated chromosomes - Ditto: metaphase stage, ring- and cross-shape of chromosomes, equatorial plate in lateral view - Ditto: anaphase stage. Separation of chromosomes, polar movement of dyads - Ditto: telophase, the new cell wall is formed between the two daughter cells - Ditto: metaphase of the second (homeotypic) division, two mitotic figures are present - Ditto: pollen tetrads. Four nuclei are formed after the second division, each bearing the haploid number of chromosomes. Formation of cell walls - Ditto: uninuclear microspores after the separation of the daughter cells - Ditto: telophase of the third division. The generative nucleus remains on the cell wall - Ditto: mature two nucleate pollen grain at the time of shedding. Each pollen grain possesses a tube cell and a generative cell - Causal relations between crossing-over and chiasmata; separation of chromatid tetrads - The crossing-over: breakages, healing - Fine structure of genes: crosses of mutants of the coli phage T4 - Localization of genes in chromosomes: chromosome aberrations - Chromosome mutations: ring-chromosomes, deletions, duplications, deletion of terminal segments, inversions, translocations - Extra chromosomes: karyotype of a human with Down’s syndrome (trisomy 21, mongolism) - Sex chromatin: Barr bodies (sex chromatin) in human female epithelial and nerve cells, 2 pictures - Replication: macronucleus before division in the ciliate Euplotes - Replication of chromosomes: introduction of radioactively labelled thymidine - Replication of chromosomes: distribution of radioactively labelled thymidine by mitoses - Equatorial plate showing four large chromosomes. Metaphase of first cleavage (mitosis) of Ascaris - Germ plasm, somatic cells: chromosome diminuition in Ascaris.

Gene and Molecule: This series was conceived to not only present the results of research, but also to show the experimental basis, and to allow the students to take part in the intellectual process of development of science. - Topics: Providing the material structure of the gene. Structural characteristics of DNA. Identical replication as a cause of hereditary constancy. DNA, RNA and protein synthesis as causes of character formation. Genetic code and molecular mechanisms in mutations. - Specialized didactic guiding ideas: Relations between structure and function on a molecular level. Explanation of genetic observations by means of characteristics and reactions of molecules. Problematization of the results by illustration of the hypotheses, methods and experiments, which lead to the results. I. DNA, the hereditary substance - Transformation in Streptococcus pneumoniae - DNA-content of various cells - Hereditary substances of bacteriophages (phages) - Electron micrograph of T2 phages - Reproduction of the phage T2 - Transmission of DNA into human cells - II. Structure of DNA - Nucleotides and their components - Relative components of bases in various DNA - Hydrogen bonding between bases - Structure of the double helix - Electron micrograph of phage-DNA - Electron micrograph of sections through bacterial cells (E. coli) - III. Replication of DNA - Models of replication - Prediction of density of replicated DNA - Density gradient centrifugation - Replicating DNA molecule I. - Replicating DNA molecule II. - IV. DNA and RNA - Differences between DNA and RNA - Fractionation of cell components by centrifugation - Synthesizing ability of components - Function of ribosomes - Structure of ribosomes - Amino acid-tRNA-complexes - Specifity of tRNA - Kinds of RNA in the cell - Experiments with artificial messengers - Polysomes on bacterial DNA - Electron micrograph of RNA-phages - Coat protein-gene of an RNA-phage - Summary: replication, transcription, translation - V. Genetic code and mutation - Colinearity between nucleotide- and amino-acid sequence - Frame shift mutations - Triplet-binding test - The genetic code - Relations between codon and anticodon - Begin of protein synthesis - Section of phage RNA - Chemical mutagenesis - Effect of mutations - VI. Synthesis, structure, and function of proteins - Protein-synthesizing complex I - Protein-synthesizing complex II - Secondary structure of proteins: a helix - Secondary structure of proteins: b-pleated sheath - Tertiary structure of a protein: b-chain of haemoglobin - Sickle cell anaemia, erythrocytes - Molecular interpretation.