Skip to main content
Ch. 2 - Transmission Genetics
Sanders - Genetic Analysis: An Integrated Approach 3rd Edition
Sanders3rd EditionGenetic Analysis: An Integrated ApproachISBN: 9780135564172당신이 사용하는 게 아니라요?교과서 변경
2장, 문제 8c

Determine whether the statements below are true or false. If a statement is false, provide the correct information or revise the statement to make it correct.
A test cross between a heterozygous parent and a homozygous recessive parent is expected to produce a 1:1 genotypic and phenotypic ratio.

검증된 단계별 안내
1
Understand the concept of a test cross: A test cross is performed to determine the genotype of an individual with a dominant phenotype by crossing it with a homozygous recessive individual.
Identify the genotypes involved: A heterozygous parent has the genotype Aa, where 'A' is the dominant allele and 'a' is the recessive allele. A homozygous recessive parent has the genotype aa.
Set up the Punnett square: Place the alleles of the heterozygous parent (A and a) on one axis and the alleles of the homozygous recessive parent (a and a) on the other axis. Fill in the squares to determine the possible offspring genotypes.
Analyze the genotypic ratio: The Punnett square will show that the offspring genotypes are 50% Aa (heterozygous) and 50% aa (homozygous recessive), resulting in a 1:1 genotypic ratio.
Analyze the phenotypic ratio: Since 'A' is dominant, the Aa offspring will display the dominant phenotype, while the aa offspring will display the recessive phenotype. This also results in a 1:1 phenotypic ratio. Therefore, the statement is true.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
3m
도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Test Cross

A test cross is a genetic cross performed to determine the genotype of an individual exhibiting a dominant phenotype. This is done by crossing the individual with a homozygous recessive individual. The offspring's phenotypes reveal the unknown genotype based on the ratios observed in the progeny.
추천 영상:
가이드 코스
26:08
Trihybrid Cross

Heterozygous and Homozygous

Heterozygous refers to an organism that has two different alleles for a particular gene, while homozygous refers to an organism with two identical alleles. In the context of a test cross, a heterozygous parent (e.g., Aa) is crossed with a homozygous recessive parent (e.g., aa) to analyze the inheritance patterns of traits.
추천 영상:
가이드 코스
04:37
Variations on Dominance

Genotypic and Phenotypic Ratios

Genotypic ratios represent the relative frequencies of different genotypes in the offspring, while phenotypic ratios represent the relative frequencies of observable traits. In a test cross between a heterozygous and a homozygous recessive parent, the expected ratios are 1:1 for both genotypes (Aa:aa) and phenotypes (dominant:recessive), confirming the inheritance patterns.
추천 영상:
가이드 코스
07:52
Gamete Genotypes
관련 실천
교과서 질문

Determine whether the statements below are true or false. If a statement is false, provide the correct information or revise the statement to make it correct.


The outcome of a trihybrid cross is predicted by the law of segregation.

526
views
교과서 질문

Determine whether the statements below are true or false. If a statement is false, provide the correct information or revise the statement to make it correct.

Reciprocal crosses that produce identical results demonstrate that a strain is pure-breeding.

498
views
교과서 질문

Determine whether the statements below are true or false. If a statement is false, provide the correct information or revise the statement to make it correct.

If a woman is heterozygous for albinism, an autosomal recessive condition that results in the absence of skin pigment, the proportion of her gametes carrying the allele that allows pigment expression is expected to be 75%.

477
views
교과서 질문

If a chi-square test produces a chi-square value of 7.83 with 4 degrees of freedom,


Above what chi-square value would you reject the chance hypothesis for an experiment with 7 degrees of freedom?

431
views
교과서 질문

Determine whether the statements below are true or false. If a statement is false, provide the correct information or revise the statement to make it correct.

If a dihybrid cross is performed, the expected genotypic ratio is 9:3:3:1.

443
views
교과서 질문

Determine whether the statements below are true or false. If a statement is false, provide the correct information or revise the statement to make it correct.

A student uses the product rule to predict that the probability of flipping a coin twice and getting a head and then a tail is 1/4.

457
views