Name: test cross in genetic inheritance
Uploaded: 2021-04-07T12:12:00.000Z
Duration: 1 min 50 s
Channel: JoVE

- [Anlat&#x131;c&#x131;] Bir test &#xE7;apraz&#x131;, bir organizman&#x131;n genotipini belirlemede, bezelye bitkisindeki mor &#xE7;i&#xE7;ek rengi gibi bask&#x131;n &#xF6;zellikleri ortaya &#xE7;&#x131;karmada kullan&#x131;lan bir tekniktir.
 &#xC7;&#xFC;nk&#xFC; bask&#x131;n versiyon ya da bir genin aleli &#xE7;ekinik alelin &#xFC;zerinde, homozigot bask&#x131;n genotipli organizmalarda ortaya &#xE7;&#x131;kacakt&#x131;r, iki bask&#x131;n alel, heterozigot genotipli organizmalarda, bir bask&#x131;n alelle ayn&#x131; olarak ortaya &#xE7;&#x131;kacakt&#x131;r.
 Bilinmeyen genotipin mor &#xE7;i&#xE7;ekli bezelye bitkisi &#xE7;ekinik fenotip, beyaz &#xE7;i&#xE7;e&#x11F;i olan bir bezelye bitkisiyle &#xE7;aprazlanabilir.
Bu nedenle, homozigot &#xE7;ekinik genotip k&#xFC;&#xE7;&#xFC;k p, k&#xFC;&#xE7;&#xFC;k p i&#xE7;ermeleriyle bilinirler.
 Bir senaryoda, d&#xF6;llerin tamam&#x131; test &#xE7;apraz&#x131;ndan geliyorsa, bask&#x131;n fenotip g&#xF6;r&#xFC;nt&#xFC;s&#xFC;, bilinmeyen ebeveyn mor &#xE7;i&#xE7;ekler i&#xE7;in homozigot bask&#x131;n olmal&#x131;d&#x131;r.
 E&#x11F;er t&#xFC;m d&#xF6;ller heterozigotsa, &#xE7;ekinik ebeveynden bir &#xE7;ekinik alel al&#x131;yorsa, ve di&#x11F;er ebeveynden bir bask&#x131;n alel al&#x131;yordur.
Ancak, e&#x11F;er d&#xF6;ldeki bask&#x131;n fenotip organizma say&#x131;s&#x131; ile &#xE7;ekinik fenotip organizma say&#x131;s&#x131; e&#x15F;itse, bilinmeyen ebeveyn heterozigottur.
 T&#xFC;m d&#xF6;ller, &#xE7;ekinik alellerini yine de &#xE7;ekinik ebeveynden al&#x131;r.
 Heterozigot ebeveynden bask&#x131;n bir alel alan d&#xF6;llerin yar&#x131;s&#x131; ve bask&#x131;n fenotip g&#xF6;sterir, ancak heterozigot ebeveynden &#xE7;ekinik alelin ikinci kopyas&#x131;n&#x131; alan di&#x11F;er yar&#x131; ise &#xE7;ekinik fenotip g&#xF6;sterir.

Miko, Ilona. 2008. "Test Haçları." Doğa Eğitimi 1 (1): 136. [<a href="https://www.nature.com/scitable/topicpage/test-crosses-585">Kaynak</a>]

Reid, James B. ve John J. Ross. 2011. "Mendel'in Genleri: Tam Bir Moleküler Karakterizasyona Doğru" Genetik 189 (1): 3–10. [<a href="https://doi.org/10.1534/genetics.111.132118">Kaynak</a>]

Çapraz test

Test Cross

Aleller, ayn&#x131; genin farkl&#x131; bi&#xE7;imleridir. &#x130;nsanlar ve di&#x11F;er diploid organizmalar, her bir ebeveynden birer tane olmak &#xFC;zere, her genin iki alelini miras al&#x131;r

Bir alel, etkileri ayn&#x131; gen konumunda ba&#x15F;ka bir alel taraf&#x131;ndan maskelenirse &#xE7;ekiniktir. &#xD6;rne&#x11F;in bezelye bitkilerinin &#xE7;i&#xE7;ekleri mor veya beyaz olabilir. Bu durumda, beyaz &#xE7;i&#xE7;ekler &#xE7;ekiniktir &#xE7;&#xFC;nk&#xFC; mor &#xE7;i&#xE7;ekler i&#xE7;in alelin tek bir kopyas&#x131;, beyaz &#xE7;i&#xE7;ekler i&#xE7;in alele sahip olsalar bile, mor &#xE7;i&#xE7;ekli bir bitkiye neden olur.

Bir organizma bilinen bir resesif &#xF6;zellik sergiliyorsa, organizman&#x131;n genotipini &#x2014;kal&#x131;tsal alel &#xE7;iftini&#x2014; belirlemek basittir. Yaln&#x131;zca bir genotip, pp (iki resesif alel) beyaz &#xE7;i&#xE7;ekler &#xFC;retir.

&#x2014;Mor &#xE7;i&#xE7;ekleri olan bezelye bitkisi gibi&#x2014; bask&#x131;n bir &#xF6;zelli&#x11F;i olan bir organizma i&#xE7;in genotipi belirlemek o kadar kolay de&#x11F;ildir. &#x130;ki genotip, PP ve Pp , mor &#xE7;i&#xE7;ekler &#xFC;retir.

Bilim adamlar&#x131;, basit bask&#x131;n &#xF6;zellikler sergileyen organizmalar&#x131;n genotiplerini belirlemek i&#xE7;in geri &#xE7;aprazlama kullan&#x131;r. Bir geri &#xE7;aprazlama, s&#xF6;z konusu organizman&#x131;n, bask&#x131;n &#xF6;zelli&#x11F;inin resesif kar&#x15F;&#x131;l&#x131;&#x11F;&#x131;n&#x131; g&#xF6;steren bir organizman&#x131;n &#xFC;remesini veya melezlenmesini i&#xE7;erir.

Mor &#xE7;i&#xE7;ekli bir bezelye bitkisi i&#xE7;in yap&#x131;lan geri &#xE7;aprazlamada, bitki beyaz &#xE7;i&#xE7;ekleri olan ( pp genotipi) bir bezelye bitkisiyle yeti&#x15F;tirilir. Ortaya &#xE7;&#x131;kan yavrular&#x131;n &#xE7;i&#xE7;ek rengi, mor &#xE7;i&#xE7;ekli ebeveynin homozigot ( PP ) veya heterozigot ( Pp ) oldu&#x11F;unu ortaya &#xE7;&#x131;kar&#x131;r.

Bitki homozigotsa, t&#xFC;m yavrular, bask&#x131;n P alellerinden birini ve di&#x11F;er ebeveynin resesif p alellerinden birini miras al&#x131;r. Bask&#x131;n aleller resesif alelleri maskeledi&#x11F;inden, t&#xFC;m yavrularda bask&#x131;n &#xF6;zellik olan mor &#xE7;i&#xE7;ekler olacakt&#x131;r.

Bitki heterozigotsa, yavrular&#x131;n yakla&#x15F;&#x131;k % 50&#x27;si resesif p alelini ve di&#x11F;er ebeveynden ba&#x15F;ka bir resesif aleli miras al&#x131;r. Bu nedenle, bu &#xE7;aprazlamadan gelen yavrular&#x131;n yakla&#x15F;&#x131;k yar&#x131;s&#x131; beyaz &#xE7;i&#xE7;eklere sahip olacakt&#x131;r. Bu &#x15F;ekilde, geri &#xE7;aprazlama, bilinmeyen ebeveyn genotiplerini ortaya &#xE7;&#x131;karabilir.

Çapraz Test

Alleles are different forms of the same gene. Humans and other diploid organisms inherit two alleles of every gene, one from each parent.

An allele is ...

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Education

JoVE Core

Molecular Biology

Moleküler Biyoloji

Unit 2

Ünite 2

Analyzing Gene Expression and Function

Gen İfadesinin ve İşlevinin Analizi

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

test cross in genetic inheritance

A test cross is a genetics tool used to determine the genotype of an organism with a dominant trait. It helps reveal whether the dominant individual is homozygous or heterozygous by crossing it with a recessive individual.

The outcome of the cross shows the hidden genotype. If any offspring show the recessive trait, the dominant parent must carry one recessive allele. If all offspring show the dominant trait, the dominant parent is likely homozygous dominant.

Test crosses are common in basic inheritance studies. They help students connect visible traits to the alleles behind them and make predictions about offspring using simple genetic crosses.

Test Cross in Genetic Inheritance

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test cross

A test cross is a genetics tool used to determine the genotype of an organism with a dominant trait. It helps reveal whether the dominant individual is homozygous or heterozygous by crossing it with a recessive individual. The outcome of the cross shows the hidden genotype. If any offspring show the recessive trait, the dominant parent must carry one recessive allele. If all offspring show the dominant trait, the dominant parent is likely homozygous dominant. Test crosses are common in basic...

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Gene Interaction Maps in Epistasis

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key terms and concepts

Learn how a test cross reveals whether a dominant organism is homozygous or heterozygous by crossing it with a recessive individual and checking offspring traits.

Test Cross in Genetic Inheritance | JoVE K12

molecular biology

JoVE Core Moleküler Biyoloji, hücrenin moleküler süreçlerini açık ve özlü animasyonlu video dersleriyle sergiler. Buna ek olarak, bilim insanı-eylem videolarında, bu kavramların uygulaması modern laboratuvarlarda gerçek deneylerle gösterilmektedir.

Test Cross in Genetic Inheritance

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