2014 MEIOTIC SEGREGATION Výukový materiál GE 02 - 48 Tvůrce: Mgr. Šárka Vopěnková Tvůrce...

Post on 19-Jan-2016

216 views 4 download

transcript

2014

MEIOTIC SEGREGATION

Výukový materiál GE 02 - 48

Tvůrce: Mgr. Šárka Vopěnková

Tvůrce anglické verze: ThMgr. Ing. Jiří Foller

Projekt: S anglickým jazykem do dalších předmětů

Registrační číslo: CZ.1.07/1.1.36/03.0005

Tento projekt je spolufinancován ESF a SR ČR

by the sexual reproduction there develop sexual cells = gametes

gametes are haploid a gamete contains only one set of

chromosomes meiotic segregation of father and mother

chromosomes is fully coincidental

MEIOTIC SEGREGATION AND COMBINATION OF GENES

monohybridism: Segregation of one

pair of chromosomes and one pair of alleles

the genotype is Aa by segregation two

types of gametes A and a can develop with the same probability

MEIOTIC SEGREGATION AND COMBINATION OF GENES

dihybridism: segregation of two pairs

of chromosomes with two pairs of alleles

the genotype is AaBb by segregation four

types of gametes AB, Ab, aB, ab can develop with the same probability

MEIOTIC SEGREGATION AND COMBINATION OF GENES

trihybridism:segregation of three pairs

of chromosomes with three pairs of alleles

the genotype is AaBbCcby segregation eight types

of gametes ABC, Abc, AbC, Abc, aBC, aBc, abC, abc can develop with the same probability

MEIOTIC SEGREGATION AND COMBINATION OF GENES

If the letter n means the number of chromosome pairs, then it stands good:

The number of the gametes types, which develop with the same probability by meiotic segregation, is 2n

MEIOTIC SEGREGATION AND COMBINATION OF GENES

by monohybridism it is 21 = 2 types of gametes

by dihybridism it is 22 = 4 types of gametes by trihybridism it is 23 = 8 types of gametes

MEIOTIC SEGREGATION AND COMBINATION OF GENES

In the human gametocyte of the 1st order there are 23 pairs of chromosomes

that means => by meiotic segregation there can develop theoretically 223 various gamete types

there are more than 8 millions of various chromosome configurations in the gametes

gametes also combine coincidentally by the semination

MEIOTIC SEGREGATION AND COMBINATION OF GENES

genes are located on chromosomes therefore the genes segregate in the same

way as chromosomes gametes gain various combinations of

genes gametes differ due to their genotype this phenomenon is called gamete fission gamete fission is the base of Mendel´s laws

MEIOTIC SEGREGATION AND COMBINATION OF GENES

DESCRIBE THE PICTURE

MEIOTIC SEGREGATION AND COMBINATION OF GENES

DESCRIBE THE PICTURE

MEIOTIC SEGREGATION AND COMBINATION OF GENES

DESCRIBE THE PICTURE

MEIOTIC SEGREGATION AND COMBINATION OF GENES

CHALUPOVÁ-KARLOVSKÁ, Vlastimila. Obecná biologie: středoškolská učebnice : evoluce, biologie buňky, genetika : s 558 řešenými testovými otázkami. 2., opr. vyd. Olomouc: Nakladatelství Olomouc, 2010, 206 s. ISBN 978-80-7182-282-0

SOURCES