KBK genetika.ppt

G E N E T I C SG E N E T I C S

DEFINISI.DEFINISI. = Ilmu yang mempelajari tentang = Ilmu yang mempelajari tentang

sifat, karakter, penyakit atau sifat, karakter, penyakit atau cacat cacat yang diturunkan dari orang- yang diturunkan dari orang-tua tua kepada turunan nya, dan kepada turunan nya, dan cara-cara- cara penurunannya. cara penurunannya.

I. Inheritansi Mendel.I. Inheritansi Mendel.

Materi Kuliah.Materi Kuliah.– 1. Hipotesa Mendel.1. Hipotesa Mendel.– 2. Persilangan Mendel Monohibrid.2. Persilangan Mendel Monohibrid.– 3. Kaidah / Hukum Mendel-I.3. Kaidah / Hukum Mendel-I.– 4. Persilangan Mendel di-, tri, dan Multi 4. Persilangan Mendel di-, tri, dan Multi

hibrid.hibrid.– 5. Kaidah / Hukum Mendel-II.5. Kaidah / Hukum Mendel-II.– 6. Inheritansi Non-Mendel.6. Inheritansi Non-Mendel.– 7. Pedigree.7. Pedigree.– 8. Probabilitas Turunan.8. Probabilitas Turunan.

I. Inheritansi MendelI. Inheritansi Mendel

1. Mendel Hypothesis.1. Mendel Hypothesis.– a. Sepasang sifat dibawakan oleh a. Sepasang sifat dibawakan oleh

sepasang faktor.sepasang faktor.– b. Salah satu faktor dominan terhadap b. Salah satu faktor dominan terhadap

alel nya.alel nya.– c. Kedua faktor terpisah dalam dua c. Kedua faktor terpisah dalam dua

gamet yang berbeda.gamet yang berbeda.

I. Inheritansi Mendel.I. Inheritansi Mendel.2. Persilangan Monohibrid.2. Persilangan Monohibrid.

P.P. ♂ Black X ♀ White F2.♂ Black X ♀ White F2.

BBBB bb bb

G1. BG1. B b b

F1.F1. Bb Bb

(Black)(Black)

G2. B - bG2. B - b

F2.ratio = Black : White = 3 : 1.F2.ratio = Black : White = 3 : 1.

♂ ♂

♀♀ BB bb

BB BBBB

BlackBlackBbBb

BlackBlack

bb BbBb

BlackBlackbbbb

WhiteWhite


3. Kaidah / Hukum Mendel-I.3. Kaidah / Hukum Mendel-I.– Bila dipersilangkan sepasang individu Bila dipersilangkan sepasang individu

dengan sepasang sifat alternatif, maka dengan sepasang sifat alternatif, maka pada turunan pertama (F1) didapatkan pada turunan pertama (F1) didapatkan sifat yang dominan, dan pada turunan sifat yang dominan, dan pada turunan kedua (F2) sifat yang dominan dan kedua (F2) sifat yang dominan dan recesif diturunkan tiga berbanding satu. recesif diturunkan tiga berbanding satu.

4. Persilangan Mendel dihybrid

P. ♂ Black-short X ♀ White-long

BBSS bbss

G1. BS bs

F1. BbSs

(Black-short)

G2. BS – Bs – bS - bs

F2.

♂ ♂

♀♀BSBS BsBs bSbS bsbs

BSBS BBSBBSSS

BBSBBSss

BbSBbSSS

BbSsBbSs

BsBs BBSBBSss

BBssBBss BbSsBbSs BbssBbss

bSbS BbSBbSSS

BbSsBbSs bbSbbSSS

bbSsbbSs

bsbs BbSsBbSs BbssBbss bbSsbbSs bbssbbss

F2. ratio = Bl-sh : Bl-Lg : Wh-sh : Wh-lg = 9 : 3 : 3 : 1.


5. Kaidah / Hukum mendel-II.5. Kaidah / Hukum mendel-II.– Bila dipersilangkan sepasang individu dengan Bila dipersilangkan sepasang individu dengan

dua pasang sifat alternatif atau lebih, maka dua pasang sifat alternatif atau lebih, maka setiap pasang sifat diturunkan tidak setiap pasang sifat diturunkan tidak tergantung satu dengan yang lain (free tergantung satu dengan yang lain (free assortment).assortment).

Bila penurunan sifat tidak mengikuti Bila penurunan sifat tidak mengikuti kaidah Mendel – I ataupun Kaidah Mendel kaidah Mendel – I ataupun Kaidah Mendel – II, maka sifat tersebut diturunkan : Non-– II, maka sifat tersebut diturunkan : Non-Mendel.Mendel.

6. Inheritansi Non-Mendel.6. Inheritansi Non-Mendel.

a. Inheritansi Dominansi Inkomplit.a. Inheritansi Dominansi Inkomplit. b. Inheritansi Intermedier.b. Inheritansi Intermedier. c. Inheritansi Epistasis.c. Inheritansi Epistasis. d. Inheritansi Gen berganda.d. Inheritansi Gen berganda. e. Inheritansi Alel berganda.e. Inheritansi Alel berganda. f. Inheritansi sehubungan dengan f. Inheritansi sehubungan dengan

perbedaan sex :perbedaan sex :– i. Inheritansi dipengaruhi perbedaan sexi. Inheritansi dipengaruhi perbedaan sex– ii. Inheritansi dibatasi perbedaan sex.ii. Inheritansi dibatasi perbedaan sex.– iii. Inheritansi terangkai pada kromosom sex.iii. Inheritansi terangkai pada kromosom sex.

7. PEDIGREE.7. PEDIGREE.

1ST GENERATION

2ND GENERATION

3RD GENERATION

4RD GENERATION

Propositus/proband

Carrier heterozygote

8. Probabilitas Turunan.8. Probabilitas Turunan.

Probabilitas turunan :Probabilitas turunan :

pria (a) : wanita (b) = 1 : 1 → a = b =½pria (a) : wanita (b) = 1 : 1 → a = b =½

Pasangan suami-isteri dengan 5 anak :Pasangan suami-isteri dengan 5 anak : (a + b)(a + b)55 = a = a55 +5 a +5 a44b +10 ab +10 a33bb22 +10 a +10 a22bb33 + 5ab + 5ab44 + +

bb55

II. SITOGENETIKA.II. SITOGENETIKA.

Materi Kuliah.Materi Kuliah.– 1. Kromosom manusia.1. Kromosom manusia.– 2. Kromatin-sex.2. Kromatin-sex.– 3. Hipotesa Lyon.3. Hipotesa Lyon.– 4. Analisa Kromosom.4. Analisa Kromosom.– 5. Terminologi Kromosom Normal.5. Terminologi Kromosom Normal.– 6. Karyotip dan Karyogram.6. Karyotip dan Karyogram.

II. Sitogenetika.II. Sitogenetika.1. Kromosom Manusia.1. Kromosom Manusia.

46 Chromosomes somatic ( 2n )46 Chromosomes somatic ( 2n )

= 22 pair of Autosomes = 22 pair of Autosomes

+ XX Sex-chrom.+ XX Sex-chrom. ♀♀

+ XY Sex-chrom. + XY Sex-chrom. ♂♂ 23 Chromosomes gametic ( n ).23 Chromosomes gametic ( n ).

= 22 Autosomes + X / Y Sex-chrom.= 22 Autosomes + X / Y Sex-chrom.

II. Sitogenetika.II. Sitogenetika.22. Kromatin-sex : a. Barr-body. Kromatin-sex : a. Barr-body..

II. Sitogenetika.II. Sitogenetika.2. kromatin-sex : b.2. kromatin-sex : b. Drumb-stick Drumb-stick..

FLUORESCENT-BODY.FLUORESCENT-BODY.

II. Sitogenetika.II. Sitogenetika.3. Hipotesa Lyon.3. Hipotesa Lyon.

a. Bila dlm sbh sel terdpt 2/lbh krom-X,a. Bila dlm sbh sel terdpt 2/lbh krom-X, → → Krom-X yg lebih Krom-X yg lebih →→ piknotik. piknotik.b. Krom. Piknotik b. Krom. Piknotik →→ inaktif secara genetik. inaktif secara genetik.c. Krom. Inaktif c. Krom. Inaktif →→ mencegah dosis mencegah dosis

berganda.berganda.d. Jumlah Sex-chromatin d. Jumlah Sex-chromatin →→ P = (jlh-X) -1. P = (jlh-X) -1.e. Krom-X yg piknotik e. Krom-X yg piknotik →→ random. random.f. Pd anak sel, krom-X piknotik f. Pd anak sel, krom-X piknotik →→ klon. klon.

II. Sitogenetika.II. Sitogenetika.4. Analisa kromosom.4. Analisa kromosom.

A. Cell-samples.A. Cell-samples.1. Lymphocytes.1. Lymphocytes.

2. Bone-marrow cells.2. Bone-marrow cells.

3. Fibroblast.3. Fibroblast.

4. Amniotic fibroblast.4. Amniotic fibroblast.

5. Trophoblast.5. Trophoblast.

II. Sitogenetika.II. Sitogenetika.4. Analisa kromosom.4. Analisa kromosom.

B. Lymphocyte cultureB. Lymphocyte culture..

1. Sampel : darah perifer.1. Sampel : darah perifer.

2. Media : HAM F-10, TC-199, dll.2. Media : HAM F-10, TC-199, dll.

3. Stimulasi Mitosis : PHA, Concovalin-A.3. Stimulasi Mitosis : PHA, Concovalin-A.

4. Anti-kontaminasi bakteri dan jamur.4. Anti-kontaminasi bakteri dan jamur.

5. Kultur di inkubator suhu = 37oC, 95% CO2 5. Kultur di inkubator suhu = 37oC, 95% CO2

& 5% O2.& 5% O2.

6. Lama kultur 67 jam.6. Lama kultur 67 jam.

II. Sitogenetika.II. Sitogenetika.4. Analisa Kromosom.4. Analisa Kromosom.

C. Harvest, preparation & staining.C. Harvest, preparation & staining.1. Harvest : - Washing 1. Harvest : - Washing →→ Buffer, Buffer,

- Bulging - Bulging →→ KCl 1%, KCl 1%, - Fixation.- Fixation.

2. Preparation.2. Preparation.3. Staining :3. Staining : a. Normal Giemsa,a. Normal Giemsa,

b. Banding staining :b. Banding staining : - Trypsin-Giemsa banding.- Trypsin-Giemsa banding. - Fluorescent-banding.- Fluorescent-banding.

II. Sitogenetika.II. Sitogenetika.5. Terminologi Kromosom Normal.5. Terminologi Kromosom Normal.

Tipe-tipe krom.Tipe-tipe krom.

Centromere

p-arm

q-arm 1 2 3

1. Metacentric chromosome.

2. Submetacentric chromosome.

3. Acrocentric chromosome.

II. Sitogenetika.II. Sitogenetika.6. Karyotip dan Karyogram.6. Karyotip dan Karyogram.

Human Karyogram.Human Karyogram.

Human Banding Chromosome.Human Banding Chromosome.

Chromosome banding.Chromosome banding.

= Band berbeda jlh dan loka si nya utk setiap kromosom.

= Band terbentuk dari Repetitive-DNA (A-T,A-T, A-T dst).

= Band penting dlm pairing kro mosom pd profase.

=Band digunakan utk mengenali pasang an kromosom dan utk menjadi map kromosom.

III. THE GENETIC III. THE GENETIC MATERIAL.MATERIAL.

THE CELL

NUCLEUS CYTOPLASM

CHROMOSOM

PROTEINNON-PROTEIN

NUCLEIC-ACID

DNA RNA

PROTEIN COMPLEX

HISTONE NONHISTONE

1. THE GENETIC MATERIAL.1. THE GENETIC MATERIAL.1.1.The Search of the Genetic 1.1.The Search of the Genetic

Material.Material.1.1.1. The Principal Characteristics of 1.1.1. The Principal Characteristics of

Genetic Genetic Material.Material.

a. It must contain, in a stable form.a. It must contain, in a stable form.b. It must Replicate accuratelyb. It must Replicate accuratelyc. It must be capable of change.c. It must be capable of change.

1.1.2. The search of the Genetic Material.1.1.2. The search of the Genetic Material.Friedrich Miescher (1869) Friedrich Miescher (1869) The The

discovery of nucleic acid.discovery of nucleic acid.Early 1920 experiments showed that Early 1920 experiments showed that

Chromosomes are carriers of Chromosomes are carriers of Hereditary Information.Hereditary Information.

The search of the Genetic The search of the Genetic Materials.Materials.

Frederick Griffith (1928)Frederick Griffith (1928) : : working with two working with two strains of Streptococcus pneumoniae strains of Streptococcus pneumoniae (pneumococcus : S- and R-strains). (pneumococcus : S- and R-strains). Unknown agent responsible for the change in Unknown agent responsible for the change in Genetic Material Genetic Material called Trasforming called Trasforming Principle. Principle.

Oswald T. Avery, Colin M. MacLeod and Oswald T. Avery, Colin M. MacLeod and Maclyn McCartyMaclyn McCarty (1930s and 1940s)(1930s and 1940s) : tried to : tried to identify the transforming principle. identify the transforming principle. They used enzyme : Nuclease, They used enzyme : Nuclease, Ribonuclease (RNase) and Deoxy-ribonuclease Ribonuclease (RNase) and Deoxy-ribonuclease (DNase) (DNase) No transformation; No transformation; and and suggested that DNA was the Genetic suggested that DNA was the Genetic Material.Material.

The search of the Genetic The search of the Genetic Material.Material.

Alfred D. Hershey and Martha Chase Alfred D. Hershey and Martha Chase (1953) : (1953) : were studying a were studying a bacteriophage bacteriophage called called T2. Phage consist of only T2. Phage consist of only DNA and protein, DNA and protein, believed that believed that DNA DNA was the Genetic Material.was the Genetic Material.

A. Gierer and G. Schramm (1956) : A. Gierer and G. Schramm (1956) : RNA was the Genetic Material of RNA was the Genetic Material of

tobacco mosaic virus (TMV)tobacco mosaic virus (TMV)

1.2. The Composition and 1.2. The Composition and Structure of DNA and RNA.Structure of DNA and RNA.

DNA and RNA DNA and RNA are Polymeres-large are Polymeres-large mole-molecules that consist of cules that consist of many similar many similar smaller molecules, smaller molecules, calledcalled Monomers Monomers Nucleotides.Nucleotides.

Nucleotide Nucleotide consists of : a Pentose consists of : a Pentose sugar, sugar, a Nitrogenous base, and a Nitrogenous base, and a Phos-a Phos- phate Group. phate Group.

A Pentose sugar A Pentose sugar is Deoxyribose in DNA, is Deoxyribose in DNA, and Ribose in RNA. and Ribose in RNA.

The Composition and Structure of The Composition and Structure of DNA and RNA.DNA and RNA.

A Nitrogen base :A Nitrogen base : the Purines the Purines nine-membered, nine-membered,

doubleringed doubleringed structures; and the structures; and the Pyrimidines Pyrimidines six-mem six-mem bered, single-ringed bered, single-ringed structures.structures.

The Purines : The Purines : Adenine (A) and Guanine (G). Adenine (A) and Guanine (G).

The Pyrimidines : The Pyrimidines : Thymine (T), Cytosine (C), and Uracil (U).Thymine (T), Cytosine (C), and Uracil (U).

A combination of a sugar and a base A combination of a sugar and a base a a Nucleoside, and addition of a Phosphate Nucleoside, and addition of a Phosphate a a Nucleotide.Nucleotide.

1.3. The DNA Double Helix.1.3. The DNA Double Helix.

James D. Watson and Francis H.C. James D. Watson and Francis H.C. Crick (1953) , Crick (1953) , published a model for published a model for physical and physical and chemical structure chemical structure of DNA molecuof DNA molecu les les Double Double Helix. Helix.

The model came primarily from : The model came primarily from : Erwin Chargaff’s studied and X-Erwin Chargaff’s studied and X-

ray ray diffraction by Rosalind Franklin diffraction by Rosalind Franklin and and Maurice H.F. Wilkins.Maurice H.F. Wilkins.

The DNA Double Helix.The DNA Double Helix.

Base Composition Studies Base Composition Studies by Erwin Chargaff.by Erwin Chargaff. – By chemical treatment, they showed By chemical treatment, they showed

that DNA in a double-stranded has a that DNA in a double-stranded has a 50% of the bases were Purines (Pu) 50% of the bases were Purines (Pu) and 50% were Pyrimidines (Py). and 50% were Pyrimidines (Py).

– The amount of Adenine (A) was equal The amount of Adenine (A) was equal to Cytosine (C) to Cytosine (C) Chargaff rules; and Chargaff rules; and

the A/T ratio = 1, the the A/T ratio = 1, the G/C ratio = 1, G/C ratio = 1, and the and the (A + G) / (C + T) ratio = 1.(A + G) / (C + T) ratio = 1.


X-ray Diffraction Studies by X-ray Diffraction Studies by Rosalind Franklin and Maurice Rosalind Franklin and Maurice H.E. WilkinsH.E. Wilkins. . Concluded that : Concluded that : DNA is DNA is a helical structure with a helical structure with two two distinctive regularities of distinctive regularities of 0.34 nm 0.34 nm and 3.4 nm along the and 3.4 nm along the axis of the axis of the molecule (1 nm = molecule (1 nm = 1010-9-9 meter=10 A). meter=10 A).

The DNA Double Helix.The DNA Double Helix. The main features of Watson-The main features of Watson-

Crick’s double-helical model.Crick’s double-helical model.1. The DNA molecules consists of two 1. The DNA molecules consists of two poly-nucleotide chains wound around poly-nucleotide chains wound around each other in a right-handed double each other in a right-handed double helix (a clockwise).helix (a clockwise).

2. The two chains are antiparalel 2. The two chains are antiparalel (an oriented in opposite direction) (an oriented in opposite direction) one strand oriented in the 5’-to-3’ way one strand oriented in the 5’-to-3’ way and the other strand orien-ted 3’-to-5’ and the other strand orien-ted 3’-to-5’ the head of one chain is against the the head of one chain is against the tail of the other chain and vice versa.tail of the other chain and vice versa.


3. The sugar-phosphate backbones are on 3. The sugar-phosphate backbones are on the outsides of the double helix, with the the outsides of the double helix, with the bases oriented toward the central axis.bases oriented toward the central axis.

4. The bases in each of the two 4. The bases in each of the two polynucleo-tide chains are bonded polynucleo-tide chains are bonded together by hydrogen bonds, which are together by hydrogen bonds, which are relatively weak chemical bonds. A-T bond relatively weak chemical bonds. A-T bond with two hydrogen bonds, and G-C bond with two hydrogen bonds, and G-C bond with three hydrogen bonds. The specific with three hydrogen bonds. The specific A-T and G-C pairs are called A-T and G-C pairs are called Complementary base-pairs.Complementary base-pairs.


5. The base pairs are 0.34 nm apart in the 5. The base pairs are 0.34 nm apart in the DNA helix. A complete (360DNA helix. A complete (36000) turn of the ) turn of the helix takes 3.4 nm; helix takes 3.4 nm; there are 10 base there are 10 base pairs per turn. The external diameter of pairs per turn. The external diameter of the helix is 2 nm.the helix is 2 nm.

6. Because of the way the bases bond, the 6. Because of the way the bases bond, the two sugar phosphate backbones are not two sugar phosphate backbones are not equally spaced from one another along equally spaced from one another along the helical axis, the helical axis, result in groove of result in groove of unequal size bet-ween the back-bones; unequal size bet-ween the back-bones; the major groove and the minor groove.the major groove and the minor groove.

RNA structureRNA structure.. The RNA moleculeThe RNA molecule is a polymer of RNA is a polymer of RNA

nucleotides in which the sugar is Ribose. Three nucleotides in which the sugar is Ribose. Three of the four bases in RNA are the same as those of the four bases in RNA are the same as those in DNA ; A, G, and C. The distinctive base in RNA in DNA ; A, G, and C. The distinctive base in RNA is Uracil, and that in DNA is Thymine.is Uracil, and that in DNA is Thymine.

In the cell, the various forms of RNA : In the cell, the various forms of RNA : messenger RNA (mRNA), ribosomal RNA (r-messenger RNA (mRNA), ribosomal RNA (r-RNA), and a small nuclear RNA (snRNA) are RNA), and a small nuclear RNA (snRNA) are single-stranded molecules. single-stranded molecules.

A number of Virus have RNA as their genome. In A number of Virus have RNA as their genome. In some cases, it is double stranded RNA, similar some cases, it is double stranded RNA, similar to DNA, with antiparalel strands, the sugar to DNA, with antiparalel strands, the sugar phosphate backbones and complementary base phosphate backbones and complementary base pairs form by hydrogen bonding.pairs form by hydrogen bonding.

1.5. The Organization of DNA in 1.5. The Organization of DNA in Chromosomes.Chromosomes.

The DNA in a cell is organized into physical The DNA in a cell is organized into physical structures called chromosomes.structures called chromosomes.

The full DNA sequence of an organisms The full DNA sequence of an organisms haploid set of chromosomes is its genome.haploid set of chromosomes is its genome.

In Prokaryotes, the genome is usually, but In Prokaryotes, the genome is usually, but not always, a single circular chromosome.not always, a single circular chromosome.

In Eukaryote, the genome is typically In Eukaryote, the genome is typically distributed among a number of distributed among a number of chromosomes in the cell nucleus. chromosomes in the cell nucleus.

Eukaryotes also contain a mitochondrial Eukaryotes also contain a mitochondrial genome and, in plants, a chloroplast genome and, in plants, a chloroplast genome.genome.

The Organization of DNA The Organization of DNA in in Chromosomes.Chromosomes.

- Viral Chromosomes.- Viral Chromosomes. Virus are fragments of nucleic acid Virus are fragments of nucleic acid

surrounded by proteins.surrounded by proteins. Depending on the virus, the genetic Depending on the virus, the genetic

material may be : double-stranded DNA, material may be : double-stranded DNA, single-stranded DNA, double stranded single-stranded DNA, double stranded RNA, or single-stranded RNA, and it may RNA, or single-stranded RNA, and it may be circular or linear.be circular or linear.

The genomes of some viruses are The genomes of some viruses are organized into a single chromosome, organized into a single chromosome, whereas other viruses have a segmented whereas other viruses have a segmented genome.genome.

The Organization of DNA in The Organization of DNA in Chromosomes.Chromosomes.

- Prokaryotic Chromosome.- Prokaryotic Chromosome. Most Prokaryotes contain a single, double-Most Prokaryotes contain a single, double-

stranded, circular DNA chromosome.stranded, circular DNA chromosome. The genome consist of one or more chromosomes The genome consist of one or more chromosomes

that may be circular or linear.that may be circular or linear. When a minor chromosome is dispensable to the When a minor chromosome is dispensable to the

life of the cell, it is more correctly called a life of the cell, it is more correctly called a plasmid.plasmid.

In bacteria and achaea, the chromosome is In bacteria and achaea, the chromosome is arranged in a dense clump in a region of the cell arranged in a dense clump in a region of the cell nucleoid. nucleoid.

The DNA fits into the nucleoid region of the cell in The DNA fits into the nucleoid region of the cell in part because it is supercoiled; part because it is supercoiled; the double helix the double helix has been twisted in space about its own axis.has been twisted in space about its own axis.

The amount and type of DNA supercoiling is The amount and type of DNA supercoiling is controlled by topoisomerase-enzymes.controlled by topoisomerase-enzymes.

The Organization of DNA in The Organization of DNA in Chromosomes.Chromosomes.

= Eukaryotic chromosome.= Eukaryotic chromosome. Eukaryotes have several chromosomes, Eukaryotes have several chromosomes,

Prokaryotes have a single chromosome.Prokaryotes have a single chromosome. The total amount of DNA in the haploid The total amount of DNA in the haploid

genome of a species known as the genome of a species known as the species’ C value.species’ C value.

Mammals, Birds, and Reptiles show Mammals, Birds, and Reptiles show little variation of the C value. little variation of the C value. Amphibians, insects, and plants vary Amphibians, insects, and plants vary over a wide range; tenfold or more.over a wide range; tenfold or more.

Eukaryotic chromosome.Eukaryotic chromosome.= Chromatin.= Chromatin.

Chromatin is the stainable material in a Chromatin is the stainable material in a cell nucleus; DNA and Proteins.cell nucleus; DNA and Proteins.

Chromatin structure. = The fundamental Chromatin structure. = The fundamental structure of chromatin is essentially structure of chromatin is essentially identical in all eukaryote. identical in all eukaryote. = Two major types of = Two major types of proteins in chromatin : proteins in chromatin : Histones and Nonhistones.Histones and Nonhistones.

With the electron microscope, it can see With the electron microscope, it can see stages of the cell cycle.stages of the cell cycle.

In a compact form the chromatin fiber is In a compact form the chromatin fiber is 10 nm, which characteristic “beads-on-a-10 nm, which characteristic “beads-on-a-string” morphologystring” morphology

1.2. The Composition and 1.2. The Composition and Structure of DNA and RNA.Structure of DNA and RNA.

DNA and RNADNA and RNA are Polymeres-large mole-are Polymeres-large mole-cules that consist of many similar smaller cules that consist of many similar smaller molecules, calledmolecules, called monomer monomer (nucleotides).(nucleotides).

Nucleotide contains of : Sugar pentose Nucleotide contains of : Sugar pentose (deoxyribose(deoxyribose and ribose);and ribose); Nitrogen bases Nitrogen bases (purine and pyrimidine),(purine and pyrimidine), and and PPhosphate.hosphate.– The Purines : Adenine (A) and Guanine The Purines : Adenine (A) and Guanine

(G).(G).– The Pyrimidines : Thymine (T), Cytosine The Pyrimidines : Thymine (T), Cytosine

(C), (C), and Uracil (U).and Uracil (U).

The Composition and Structure The Composition and Structure of of

DNA and RNA.DNA and RNA. A combination of a sugar pentose A combination of a sugar pentose

(deoxyri-bose or ribose) + a nitrogen (deoxyri-bose or ribose) + a nitrogen base base a a NucleosideNucleoside,,

+ a Phosphate + a Phosphate a a Nucleotide.Nucleotide. Nucleotide+nucleotide+nucleotide+Nucleotide+nucleotide+nucleotide+

………….…………… ………….…………… a a nucleic acidnucleic acid

(DNA or RNA).(DNA or RNA).

Pentose sugars : Pentose sugars : Deoxyribose and Deoxyribose and Ribose.Ribose.

C

C C

C

C

CC

C

O

O

HCOH2

HCOH2

H H HH

HH

H

HH

OH

OH

OH

OH

OH

5’

5’

4’

4’

3’

3’

2’

2’

1’

1’

DEOXYRIBOSE

RIBOSE

THE END

KBK genetika.ppt

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