Q.37 Match the type of bacteria in Group I with their respective growth properties in
Group II.
Group I Group II
P. Halophile 1. Grows optimally between 20 °C and 45 °C
Q. Piezophile 2. Grows best at low water activity
R. Mesophile 3. Grows at high level of salt
S. Xerophile 4. Grows optimally at high hydrostatic pressure
(A) P–3, Q–4, R–1, S–2
(B) P–2, Q–3, R–4, S–1
(C) P–3, Q–1, R–2, S–4
(D) P–4, Q–3, R–1, S–2
Correct Answer: (A) P-3, Q-4, R-1, S-2
Halophiles thrive in high-salt environments, piezophiles grow under high pressure, mesophiles prefer moderate temperatures, and xerophiles tolerate low water availability. Option A correctly matches each bacterium type to its defining growth property.
Definitions
Halophiles require high salt levels (e.g., 2-4.5 M NaCl) for optimal growth, often found in hypersaline environments. Piezophiles (barophiles) adapt to extreme hydrostatic pressures, like deep-sea conditions. Mesophiles grow best between 20°C and 45°C, typical for many lab bacteria. Xerophiles excel at low water activity (a_w < 0.9), surviving in dry habitats.
Option Analysis
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(A) P-3, Q-4, R-1, S-2: Matches perfectly—halophile with high salt (3), piezophile with high pressure (4), mesophile with 20-45°C (1), xerophile with low water activity (2).
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(B) P-2, Q-3, R-4, S-1: Incorrect—halophiles need salt, not low water; piezophiles need pressure, not salt.
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(C) P-3, Q-1, R-2, S-4: Wrong—piezophiles ignore temperature ranges; mesophiles do not prefer low water.
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(D) P-4, Q-3, R-1, S-2: Flawed—halophiles link to salt, not pressure; piezophiles to pressure, not salt.
Optimized Title
Halophile Piezophile Mesophile Xerophile Growth Properties: GATE BT Matching Question Solved
Introduction to Extremophile Bacteria Growth
Halophile, piezophile, mesophile, and xerophile bacteria growth properties define microbial adaptation to extreme environments, crucial for IIT JAM and GATE Biotechnology exams. This halophile piezophile mesophile xerophile growth properties guide explains matching types to conditions like salt, pressure, temperature, and water activity, with detailed solutions for competitive prep.
Core Matching Explanations
Understand halophile piezophile mesophile xerophile growth properties through precise pairings:
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Halophile (P-3): Grows at high salt levels; requires 1.5-4.5 M NaCl to balance osmotic stress.
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Piezophile (Q-4): Thrives at high hydrostatic pressure, e.g., ocean depths over 1000 atm.
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Mesophile (R-1): Optimal growth 20°C-45°C, common in soil and human environments.
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Xerophile (S-2): Best at low water activity, resisting desiccation in arid zones.
This GATE BT Q.37 matching confirms option A as correct.
Exam Relevance for IIT JAM Biotechnology
In IIT JAM Biotechnology and GATE BT, halophile piezophile mesophile xerophile growth properties test microbiology basics. Similar questions appear in previous papers, emphasizing extremophile classifications for bioremediation and astrobiology applications. Practice strengthens conceptual clarity.
