2013 kuliah 2 genetika HK mendel klas indo danInggris FAPET3
Mendelian Genetics Gregor Mendel is recognized as the father of genetics.
Mendel, who was not scientifically trained, developed his theories in the 1850’s and 1860’s, without any knowledge of cell biology or the science Photo courtesy of Wikipedia. of inheritance.
In later years, genes, chromosomes, and DNA were discovered and people began to understand how and why Mendel’s theories worked.
Robert Bakewell Gregor Mendel 1700s English Breeder of: basic genetic principles Shire horses used pea plants Leicester sheep not well understood Longhorn cattle during his life Used Mendel, G. 1866 . Experiments inbreeding on Plant Hybridization. progeny testing Transactions of the Brünn Natural History Society.
Topic of Discussion :Genetics of Animal Introduction: History and Development of Genetics .
1 Mendelism :Monohibryd and dihibryd Inheritance, 2.
Exception of Mendelsm : intermedier, linkage ,, sex 3. limited, sex inlfluenced Genetic Material I: Chromosome, DNA and Gen , 4. Abberation Multiple Allel 5.
Class Discusion: Proup of 5: Paper and PPT, Presentation.
6. Topic 1-5.
Class Discusion: Proup of 5: Paper and PPT, Presentation.
7. Topic 1-5.
8. MIDTEST
Probability in Genetics Inheritance
9.
Sex Determination , linked and crossing over 10.
Introduction to Genetics Population 11.
Factors influencen in Population 12.
Introduction to Genetics Engineering 13.
Class Discusion: Proup of 5: Paper and PPT, Presentation.
14. Topic 1-5.
Class Discusion: Proup of 5: Paper and PPT, Presentation.
15. Topic 1-5.
FINAL TEST
16
Mendel’s experiments dealt with the
relationship between an organism’s genotype
and its phenotype .Genotype – the genetic composition of an organism. Phenotype
- – the observable or measurable characteristics (called traits) of that organism.
The relationship between phenotype and genotype is expressed as the following equation:
P = G + E
P = phenotype, G = genotype, and
To understand Mendel’s principles and
the relationships between phenotype and genotype, it is necessary to understand what makesup the genetic material of animals and how this is
transferred from one generation to the next.1 . Nucleolus 5. Rough Endoplasmic Reticulum 9. Mitochondria 2. Nucleus 6. Golgi Aparatus 10. Vacuole 3. Ribosome 7. Cytoskeleton 11. Cytoplasm
Genetics Vocabulary
• Homozygous- when both alleles of a pair are the
same for a >Homozygouse Dominant- PP- Homozygous Recessive>
• Heterozygous- when the 2 alleles in the pair are
different for a - Heterozygous for flower color: Pp
Fertilization
- Takes place when a sperm cell from a male reaches the egg cell of a female
- The two haploid cells (the sperm and the egg) unite and form one complete cell or zygote
- Zygote is diploid, it has a full set of chromosome pairs
- This results in many different combinations of traits in offspring
Chromosomes
- Occur in pairs in the nucleus of all body cells except the sperm and ovum
- Each parent contributes to one-half of the pair
- The number of pairs of chromosomes is called the diploid number
- The diploid number varies species to species but is constant for each species of animal
Common Livestock Diploid Number
Cattle 30, Swine 19, Sheep 27, Goat 30, Horse 32, Donkey 31, Chicken 39, Rabbit 22 MENDELISME
Mendel proposed three principles to describe the transfer of genetic material from one generation to the next.
- The Principle of Dominance : in a heterozygous organism, one allele may conceal the presence of another allele.
- The Principle of Segregation: in a heterozygote, two different alleles segregate from each other during the formation
Assortment : the alleles
- The Principle of Independent of different genes segregate, or assort, independently of each other.
Later studies have shown that there are some important exceptions to Mendel’s Principle of Independent Assortment, but
Dominant and Recessive Genes
- In a heterozygous pair the dominant gene hides the effect of its allele
- The hidden allele is called a recessive gene
- When working problems involving genetic inheritance the dominant gene is usually written as a capital letter and the recessive gene is written as a lowercase letter (PP,pp>Black is dominant to red in cattle
- White face is dominant to color face in cattle
- Black is dominant to brown in horses
- Color is dominant to albinism
- Rose comb is dominant to single comb (chicken)
- Pea comb in chickens is dominant to single comb
• Barred feather pattern in chickens is dominant to nonbarred feather—the dominant
gene is also sex-linked
Teories of Inheritance (Conventional) Ovisma : pemilik sifat keturunan adalah ovum ( ♀ ), fungsi jantan menghasilkan cairan untuk perkembangan ovum Animalkulism
a:
pada cairan jantan ditemukan hewan2 kecil ( Spz), sbg pembawa sifat keturunan Preformasi : Loewenhook: (mikroskop) ada MH kecil dalam spermatozoa atau ada manusia kecil dlm ovum
Epigenesis : Ovum terfertilisasi oleh Spz, kmd. tumbuh sedikir demi sedikit
Pangenesis (Darwin ): dalam sel kelamin ♀ ♂ terdapat tunas 2 tumbuh menjadi MH baru setelah fertilisasi Plasma benih (Weisman ):
Gamet ♀ ♂ dibentuk oleh jar.khusus, bukan jar. tubuh
Penelitian dan Peneliti Genetika Mendel:
- From Result of Mendel
- Then, What Is Genetic Factor ?
Genetic Materials ?
W. ROUX (1883): Cromosome T. Bovery (1902): Gen bagian dari kromosom Faktor Penentu (Gen/Kromosom) di wariskan lewat GAMET (pada Anafase Meiosis I saat Separasi Kromosom homolog)
HIPOTESA SUTTON-T. BOVERY
HIPOTESA WS SUTTON-T . BOVERY:
Animal Chromosomes
1. Gen dibawa oleh kromosom
2. Satu pasang kromosom asal maternal+paternal
3. Pemindahan 1 ps kromosom saat meiosis
4. Sel benih mengandung kombinasi gen jantan dan betina
5. Kromosom homolog secara genetis berbeda, sehingga sel benih scr genetis berbeda
6. Tiap kromosome terdiri lebih dari 1 gen,
TEORI : DOMONANSI-RESESIF Sifat Tinggi : Dominan (gen T) Sifat rendah/kerdil: Resesif (gen t)
Parents (P) TT X tt Monohibrid: 1 sifat beda Gamet:T Gamet: t Di hibrid : 2 sifat beda Filial 1 (F1) Tri hibrid : 3 sifat beda Tt HIBRIDA T t Fenotip: 3:1
♂/ ♀ F2 T TT Tt Genotip : 1 : 2: 1 F2 ? tt: homosigot t Tt tt
Dominansi penuh dan semi dominant Semi Dominant: Dominansi Penuh Bunga pk 4.
Merah
X Putih Parents (P) TT X tt
Merah Muda Gamet:T Gamet: t (Tinggi) (rendah) Filial 1 (F1)
Kodominan Tt (Tinggi) RR x rr Merah putih Rr Bedanya ??? Roan/coklat
MONOHIBRID HEWAN
Warna rambut hitam (gen dominan A, pigmentasi melanin)
1.Resiprok : Kebalikan
Hh
F1 dng P resesif Pembuktian F1 homosigot
3. Test Cross :
♀ Hasil:
F1 dng parent ♂/
♀/ ♂ ♂ HH x ♀ hh
AA Hitam
Macam sistim Persilangan
Pada F2: Fenotip : 3: 1 Genotip : 1 : 2 : 1
Hitam
F1 Aa
albino
X aa
2. Back cross :
Dihidrid pada hewan
Pada marmot:x
hh kk Gamet HK Gamet : hk F1: Hh Kk x Hh Kk
- Rambut Hitam (gen H) vs putih (gen h)
- Rambut Kasar (gen K) vs rambut halus (gen h) HH KK
Gamet HK Hk hK kk HK * * * * Hk * + * + hK * * = = kk * + = O
F2
Perhitungan Matematis (Rumus estimasi)
Juml. Macam Kombi Fenotip Kombi Kombi Genoti
Sifat gamet nasi F2 F2 nasi F1 nasi p F2 beda F1 homosi got n n 2 n n n n n 2 (2 )2
2
2
3
1
2
4
2
2
2
3
2
4
16
4
4
4
9
3
8
64
8
8
8
27 Macam Gamet: n 1 Kombinasi: 1 2 Monohibrid (Aa) : 2 = 2 = 2 = (A/a) Mono hibrid : (AaxAa)=(2 ) =4 = 2 (AA,Aa,Aa,aa) Perkawinan Intermedier ( Dominansi tak sempurna )
Pd Mirabilis jalapa
P mm X MM putih merah
Mm
X Mm Merah muda ( pink) MM
Mm
2 mm
( dominansi parsial) Pada sapi Shorthorn P : RR X rr
Merah putih
Rr X Rr
Coklat RR
1 Rr
1 Mm
Rr
2 rr 1
1 Perkawinan Kodominan
Implementasinya pada ternak: Jika jumlah gamet (gen) sama dengan jumlah kromosom Maka Kombinasinya* n
30
9 Sapi 2 = 2 kombinasi gamet = 1.07 x 10 n
32
9 Kuda 2 = 2 kombinasi gamet = 4.29 x 10 n
23
6 Manusia 2 = 2 kombinasi gamet = 8.3 x 10
Note : More than a 100 or 1000 gens/ Chromosome
So, What is the conclussion: -
S u m m a r y
- Gregor Mendel is considered the father of genetics
- The amount of difference between parents and offspring is caused by genetics and the environment P= G+ E • Fertilization occurs when the sperm cell penetrates the egg and the chromosome pairs are formed again when fertilization takes place
- Genes control an animals traits
- Some genes are dominant and some are recessive
- Animals may carry two dominant or two recessive genes for a trait. They are called homozygous pairs • Animals may also carry a dominant and recessive gene pair.
They are called heterozygous pairs
• Livestock improvement is the result of using