Genetics & Laws of Inheritance

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শিক্ষামূলক নোট: এই পৃষ্ঠা একাডেমিক জীববিজ্ঞান শেখা ও পরীক্ষার প্রস্তুতির সহায়ক।

Genetics & Laws of Inheritance MCQ Bank

This page provides concept-based MCQ practice for Mendelian inheritance, chromosome behaviour, alleles, genotype, phenotype, dominance, segregation, independent assortment, linkage, mutation, molecular inheritance, and genetic probability.

Preparation checklist

Revise Mendel’s laws, monohybrid and dihybrid crosses, test cross, incomplete dominance, codominance, multiple alleles, sex-linked inheritance, pedigree logic, DNA structure, replication, transcription, translation, mutation, and chromosome-based inheritance.

Reasoning method

Genetics MCQs often require calculation and conceptual filtering. Identify the cross, write the genotype logic, decide whether the trait follows Mendelian or non-Mendelian inheritance, and then select the option that matches the predicted ratio or mechanism.

Interactive Diagnostic Membrane

Genetics & Laws of Inheritance

⏱️ Matrix Time: 15 Mins

Q1. Which phenotypic ratio represents dominant epistasis in classical genetic inheritance interactions?

a. 9:3:3:1 b. 12:3:1 c. 9:7 d. 15:1

Answer Explanation & Validity Logic: Dominant epistasis occurs when a dominant allele at one locus masks expression at another locus, producing a 12:3:1 ratio instead of the standard dihybrid 9:3:3:1.

Q2. Which enzyme relieves torsional strain ahead of the replication fork?

a. DNA Polymerase III b. RNA Primase c. DNA Topoisomerase (Gyrase) d. DNA Ligase

Answer Explanation & Validity Logic: Topoisomerases introduce temporary breaks into the DNA backbone to relieve supercoiling tension generated by helicase unwinding.

Q3. What is the primary function of the enzyme DNA ligase during DNA replication?

a. Synthesizing RNA primers b. Unwinding the DNA double helix c. Joining Okazaki fragments on the lagging strand d. Proofreading newly synthesized DNA

Answer Explanation & Validity Logic: DNA ligase catalyzes the formation of phosphodiester bonds between adjacent DNA fragments, specifically sealing the nicks between Okazaki fragments on the lagging strand.