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BAHAN GENETIK. GENETIC MATERIALS. The genetic material is consisted of :. Chromosomes. called as NUCLEOPROTEIN. Genes. reside along the chromosome. Eukaryotic Chromosomes. Located in the nucleus Each chromosome consists of a single molecule of DNA and its associated proteins
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GENETIC MATERIALS The genetic material is consisted of : Chromosomes called as NUCLEOPROTEIN Genes reside along the chromosome
Eukaryotic Chromosomes • Located in the nucleus • Each chromosome consists of a single molecule of DNA • and its associated proteins • The DNA and protein complex found in eukaryotic • chromosomes is called chromatin • 1/3 DNA and 2/3 protein • Complex interactions between proteins and nucleic acids • in the chromosomes regulate gene and chromosomal • function
Fungsi DNA • Autokatalitis (replikasisendiri) • Heterokatalitis (transkripsimenjadi RNA)
Asam Ribonukleat (RNA) • RNA merupakan benang tunggal • RNA mengandung gula ribosa • RNA mengandung pirimidin Urasil (U) sebagai pengganti Timin • Molekul lebih pendek drpd molekul DNA • Fungsi dalam sintesis protein
JUMLAH KROMOSOM Jumlah kromosom • Jumlah kromosom dasar dari suatu spesies disebut GENOM, merupakan satu set kromosom (x). • Contoh : jagung (diploid, 2n=2x=20; genom = x=10) kentang (tetraploid, 2n=4x=48, genom = x = 12) • Setiap sel somatik (2n) mengandung setengah jumlah kromosom yang diwariskan dari tetua betina (n) dan setengah jumlah kromosom dari tetua jantan (n) • Contoh : jagung (diploid, 2n=2x=20; gamet : n = x = 10) kentang (tetraploid, 2n=4x=48; gamet : n = 2x = 24)
KROMOSOM Trillium erectum TERMASUK TANAMAN DIPLOID, TRIPLOID ATAU TETRAPLOID? BERAPA GENOM TANAMAN TERSEBUT? BERAPA JUMLAH KROMOSOM PADA GAMET TANAMAN TERSEBUT?
Karyotype Tanaman Bawang Merah TERMASUK TANAMAN DIPLOID, TRIPLOID ATAU TETRAPLOID? BERAPA GENOM TANAMAN TERSEBUT? BERAPA JUMLAH KROMOSOM PADA GAMET TANAMAN TERSEBUT?
STRUKTUR KROMOSOM The essential part of a chromosome is a single very long strand of DNA. This DNA contains all the genetic information for creating and running the organism. The DNA is supported and neatly packaged by proteins bound to it. At different times, these proteins cause the DNA to be spread out like spaghetti in a bowl, or tightly condensed into the X-shaped chromosomes we can see in the microscope. Each chromosome has a central constricted region called a centromere that serves as an attachment point for the machinery of mitosis.
Chromatin structure Compacts DNA ~ 10,000 X From Miller & Therman (2001) Human Chromosomes, Springer
MORPHOLOGY OF CHROMOSOME • Individual chromsomes are recognized by arm lengths • p, short arm • q, long arm • Individual chromsomes are recognized by centromere position • metacentric • sub-metacentric • acrocentric • telocentric
Individual chromsomes are recognized by arm lengths • p, short arm • q, long arm
Karyotype The representation of entire metaphase chromosomes in a cell, arranged in order of size and other characteristics
IDEOGRAM • Diagramatic representation • of a karyotype From Miller & Therman (2001) Human Chromosomes, Springer
Chromosome in general (size, shape and number) • Diploid organisms = 2n • Two copies of autosomes • with sex chromosomes • diploid organisms have two cell-types • somatic cells = body’s cells • germ cells = gametes • human bodies ~= 1014 cells • many cell divisions => mitosis • sexual reproduction • require haploid (n) cells => meiosis Human chromosomes = 22 pairs of autosomes + sex chromosome (XX or XY)
CENTRAL DOGMAFrancis Crick, 1958 DNA Replication DNA Transcription RNA PROTEIN Translation
FUNGSI DNA dan RNA • DNA sebagaibahanketurunan, merupakan “blue print” ataucetakbiru • RNA : • mRNAmenerimakode-kodeinformasidari DNA danmembawanyaketempatsintesis protein • tRNAmengenaldanmenggerakkannukleotidabasadarisekitarselkeribosomuntuksintesis protein pada mRNA • rRNAmembentukbagiandariribosomdanbertindaksebagaipengikatpadaribosom
TRANSKRIPSI, TRANSLASI dan SINTESIS PROTEIN • TRANSKRIPSI adalah sintesis RNA dengan cetakan DNA, hanya satu pita DNA yang disalin • TRANSLASI adalah proses pembacaan susunan nukleotida pada mRNA dan sintesis rantai asam amino untuk membentuk molekul protein • SINTESIS PROTEIN
SINTESIS PROTEIN • mRNA adalah pita ribonukleotida tunggal, terdiri dari triplet-triplet (codon=kodon) yang memberi kode untuk asam amino tertentu. Ribosom melekat pada mRNA. tRNA membawa asam amino tertentu ke ribosom. • Ribosom bergerak sepanjang mRNA untuk memastikan bahwa antikodon tRNA berpasangan dengan kodon dari mRNA. Ketika antikodon melekat pada kodon, asam amino melekat pada rantai protein yang sedang dibentuk. • Susunan asam amino dalam molekul protein ditentukan oleh susunan triplet (kodon) tadi pada mRNA. Pada saat ribosom bergerak sepanjang tRNA, asam amino terangkai dengan pola tertentu untuk membentuk molekul protein tertentu.
TYPES OF RNA • mRNA contains codons which code for amino acids.
GENE EXPRESSION DNA BIOSPHERIC PHENOTYPE RNA POPULATION PROTEIN ORGANISM CELL EFFECT TISSUE