सामान्य कृषि एवं सांख्यिकी Practice Questions (Q11-15) - Plant Sciences

ICAR PG Plant Sciences 29 Jun 2024Shift 1

MCQ (Single Correct) +4 −1

The number of possible combinations in a polypeptide containing any 7 amino acids is given by the figure

किसी भी 7 अमीनो अम्लों वाले पॉलीपेप्टाइड में संभावित संयोजनों (combinations) की संख्या किस मान द्वारा दी जाती है?

$7^4$ $7^4$ $4^7$ $4^7$ $20^7$ $20^7$ $7^{20}$ $7^{20}$

ICAR PG Plant Sciences 29 Jun 2024Shift 1

MCQ (Single Correct) +4 −1

________ is a second mutation that compensates for the effect of an original, first mutation. Choose the most appropriate option from the below-mentioned options to fill in the gap:

________ एक दूसरा उत्परिवर्तन (second mutation) है जो मूल, पहले उत्परिवर्तन के प्रभाव की भरपाई (compensate) करता है। रिक्त स्थान की पूर्ति के लिए नीचे दिए गए विकल्पों में से सर्वाधिक उपयुक्त विकल्प चुनिए:

Forward mutation अग्रगामी उत्परिवर्तन Supplementary mutation पूरक उत्परिवर्तन Suppressor mutation दमनकारी उत्परिवर्तन Compensatory mutation प्रतिपूरक उत्परिवर्तन

Suppressor Mutation:

Suppressor mutation is a secondary genetic alteration that suppresses or alleviates the phenotypic consequences of an earlier (first) mutation, restoring the wild-type or near wild-type phenotype without reversing the original mutation.
Suppressors are categorized into:

Intragenic suppressors: Occur within the same gene as the first mutation (e.g., a compensatory insertion near an earlier deletion that restores reading frame).
Intergenic (extragenic) suppressors: Occur in a different gene (e.g., a mutant tRNA gene whose anticodon recognizes a nonsense stop codon introduced by the primary mutation).
- Forward mutation: Mutation from wild type to mutant form.
Reverse/back mutation: Direct reversion of the mutant allele back to the wild-type sequence.

Correct Answer: Option 3 (Suppressor mutation).

विस्तृत व्याख्या:

Suppressor Mutation (सप्रेसर/दमनकारी उत्परिवर्तन):

Suppressor mutation is a secondary genetic alteration that suppresses or alleviates the phenotypic consequences of an earlier (first) mutation, restoring the wild-type or near wild-type phenotype without reversing the original mutation.
Suppressors are categorized into:

Intragenic suppressors: Occur within the same gene as the first mutation (e.g., a compensatory insertion near an earlier deletion that restores reading frame).
Intergenic (extragenic) suppressors: Occur in a different gene (e.g., a mutant tRNA gene whose anticodon recognizes a nonsense stop codon introduced by the primary mutation).
- Forward mutation: Mutation from wild type to mutant form.
Reverse/back mutation: Direct reversion of the mutant allele back to the wild-type sequence.

Correct Answer: Option 3 (Suppressor mutation).

Explanation not matching this question? क्या व्याख्या इस प्रश्न से मेल नहीं खा रही? Report

ICAR PG Plant Sciences 29 Jun 2024Shift 1

MCQ (Single Correct) +4 −1

In the case of Lac operon, the presence of glucose in the cell growing media will lead to

लैक ऑपेरॉन (Lac operon) के संदर्भ में, कोशिका संवर्धन माध्यम में ग्लूकोज (glucose) की उपस्थिति के कारण क्या होगा?

Increased induction बढ़ा हुआ प्रेरण Catabolite repression अपचयी दमन Slow induction धीमा प्रेरण Zero effect induction शून्य प्रभाव प्रेरण

ICAR PG Plant Sciences 29 Jun 2024Shift 1

MCQ (Single Correct) +4 −1

The process of 'turning on the expression of genes' due to environmental conditions is called

पर्यावरणीय परिस्थितियों के कारण 'जीन की अभिव्यक्ति को सक्रिय करने' (turning on gene expression) की प्रक्रिया क्या कहलाती है?

Constitutive expression संविधिक/नित्य अभिव्यक्ति Induction प्रेरण Repression दमन Enzymatic catabolism एंजाइमी अपचय

ICAR PG Plant Sciences 29 Jun 2024Shift 1

MCQ (Single Correct) +4 −1

Which one of the following statements about the mode of reproduction is NOT correct?

प्रजनन की विधियों (modes of reproduction) के बारे में निम्नलिखित में से कौन सा कथन सही नहीं है?

Self-fertilization, where pollen from a plant will fertilize ovules of the same plant स्व-निषेचन, जहाँ एक पौधे का परागकण उसी पौधे के बीजांड को निषेचित करता है Cross-pollination, where pollen from one plant can only fertilize a different plant पर-परागण, जहाँ एक पौधे का परागकण केवल किसी दूसरे पौधे को निषेचित कर सकता है Asexual propagation, where the new plant is genetically identical to its parent अलैंगिक प्रवर्धन, जहाँ नया पौधा अपने जनक के आनुवंशिक रूप से समान होता है Apomixis, where seeds are produced asexually and the new plant is quite improved and different from its parents एपोमिक्सिस, जहाँ बीज अलैंगिक रूप से बनते हैं और नया पौधा अपने जनकों से काफी उन्नत और भिन्न होता है