QCM : Genetics and Inheritance Fundamentals — 10 questions

Questions et réponses du QCM

1. Which statement best explains how alleles relate to inherited traits?

Alleles are proteins that directly move from parent to offspring during cell division
Different alleles are alternative versions of the same gene that can produce different trait outcomes
Alleles are entire chromosomes that determine whether an organism is haploid or diploid
Alleles are identical copies of a gene that always produce the same phenotype

Different alleles are alternative versions of the same gene that can produce different trait outcomes

Explication

Alleles are different versions of a gene, and their combination helps determine the trait an individual shows. The distractors confuse alleles with chromosomes or proteins, or incorrectly claim all alleles produce the same phenotype.

2. What is the primary function of genetic information stored in DNA?

To control the rate of cell division
To encode traits through the alleles it contains
To determine the organism's physical size
To produce proteins directly in the cell

To encode traits through the alleles it contains

Explication

Genetic information stored in DNA encodes traits through the alleles it contains, which determine the organism's characteristics. The other options are related to gene expression or cell processes but are not the primary function of genetic information.

3. What was Mendel’s key experimental approach in studying inheritance?

He crossed many species at once to compare how different traits blended together
He studied a single plant over time to see how its traits changed with age
He crossed pure pea plant lines that differed in one character and then tracked the offspring generations
He observed random mating in wild plants and inferred inheritance from population averages

He crossed pure pea plant lines that differed in one character and then tracked the offspring generations

Explication

Mendel’s method was to cross pure lines that differed by one trait, such as flower color, and follow the F1 and F2 generations. This controlled approach let him identify patterns of inheritance rather than simple blending.

4. What is the primary purpose of test crosses in Mendelian genetics?

To produce offspring with a specific phenotype
To identify linked genes on the same chromosome
To determine the genotype of an individual with an unknown genetic makeup
To increase genetic variation in a population

To determine the genotype of an individual with an unknown genetic makeup

Explication

Test crosses are used to deduce the genotype of an individual with an unknown genotype by crossing it with a homozygous recessive individual and analyzing the offspring phenotypes.

5. What best describes how genetic information is organized in a diploid organism?

It is stored in DNA, with genes present in two copies for each chromosome pair
It is stored in the cell membrane, with one version of each trait per organism
It is stored in RNA, with alleles appearing only after fertilization
It is stored in proteins, with one copy of each gene in every cell

It is stored in DNA, with genes present in two copies for each chromosome pair

Explication

Genetic information is stored in DNA, and a diploid organism has two copies of each chromosome, so each gene is represented twice. The other options confuse DNA with other cell components or incorrectly describe chromosome number.

6. When did Gregor Mendel establish the fundamental principles of inheritance through his experiments with pea plants?

In the early 20th century, around 1900-1910
In the mid-19th century, around 1856-1863
In the late 19th century, around 1890-1900
In the late 18th century, around 1780-1790

In the mid-19th century, around 1856-1863

Explication

Gregor Mendel conducted his experiments between 1856 and 1863, which led to the formulation of the laws of inheritance that are foundational to genetics.

7. What does the F2 generation in Mendel’s monohybrid experiments reveal?

It shows that offspring always resemble the mother more than the father
It shows a 1:1 phenotype ratio because only one allele is passed on to each offspring
It shows a 3:1 phenotype ratio, with the recessive trait reappearing in about one quarter of offspring
It shows that both parental traits disappear permanently after the first cross

It shows a 3:1 phenotype ratio, with the recessive trait reappearing in about one quarter of offspring

Explication

In Mendel’s monohybrid crosses, F2 offspring typically show a 3/4 dominant to 1/4 recessive phenotype ratio, revealing that the recessive trait was masked in F1 but still present. The other choices contradict the observed pattern.

8. How do dominance relationships between alleles differ from the concept of independent assortment in genetics?

Dominance relationships describe how alleles influence phenotype within an individual, while independent assortment explains how different genes segregate into gametes independently during meiosis.
Dominance relationships explain how alleles are inherited from parents, while independent assortment describes the physical location of genes on chromosomes.
Dominance relationships are only relevant for linked genes, whereas independent assortment applies exclusively to genes on different chromosomes.
Dominance relationships determine the likelihood of alleles being inherited together, whereas independent assortment describes the dominance of one allele over another.

Dominance relationships describe how alleles influence phenotype within an individual, while independent assortment explains how different genes segregate into gametes independently during meiosis.

Explication

Dominance relationships concern how alleles affect phenotype within an individual, such as whether a dominant allele masks a recessive one, whereas independent assortment refers to how different genes segregate into gametes independently during meiosis, affecting inheritance patterns across multiple genes.

9. Who is credited with proposing the concept of dominance relationships between alleles in genetics?

Charles Darwin
Thomas Hunt Morgan
Gregor Mendel
Watson and Crick

Gregor Mendel

Explication

Gregor Mendel is credited with proposing the concept of dominance relationships between alleles based on his experiments with pea plants, where he observed that some traits are expressed in heterozygotes while others are masked.

10. What is the primary effect of crossing-over during meiosis on linked genes?

It creates new combinations of alleles, thereby increasing genetic diversity among gametes.
It causes linked genes to become physically separated onto different chromosomes.
It increases the likelihood that linked genes will be inherited together.
It prevents genes on the same chromosome from segregating independently.

It creates new combinations of alleles, thereby increasing genetic diversity among gametes.

Explication

Crossing-over during meiosis results in recombinant gametes by exchanging genetic material between homologous chromosomes, which increases genetic diversity. This process can break the physical linkage of genes that are close together, creating new allele combinations.

Révisez avec les flashcards

Mémorisez les réponses avec 9 flashcards sur Genetics and Inheritance Fundamentals.

Genetic information — stored where?

In DNA, encoding traits through alleles.

Genetic information storage

Stored in DNA, encodes traits

Mendel's monohybrid experiment — purpose?

To analyze inheritance of a single gene trait.

Voir les flashcards →

Approfondir avec la fiche

Consultez la fiche de révision complète sur Genetics and Inheritance Fundamentals.

Voir la fiche →

Cours similaires

Actions et mouvement

Physique

Gel pour les veines

Grandeurs composées et conversions

Mathématiques

Réciproque de Pythagore

Mathématiques

Réussir ses études efficacement

Les émotions humaines

Crée tes propres QCM

Importe ton cours et l'IA génère des QCM avec corrections en 30 secondes.

Générateur de QCM