Explanation

A solid changes directly into a gas without becoming liquid

Example: Camphor, dry ice (solid CO₂), and iodine undergo sublimation.

Explanation

 In bacterial cells, RNA makes up about 6% of the total cell weight, which is relatively high compared to DNA due to the abundance of ribosomal RNA (rRNA).

Explanation

We are given:

• $x+y=6$

• $xy=5$

We are asked to find:
$x^2 + y^2$

Step-by-step solution:

Use the identity:

x^2+y^2=(x+y)^2−2xy

Substitute the given values:

$$$$x^2+y^2=(6)^2−2(5)=36−10=26

Explanation

An arithmetic sequence is a sequence of numbers where the difference between consecutive terms is constant.

Let’s check each option:

B. 72, 73, 75, 78
Differences: +1, +2, +3 → Not arithmetic

A. 31, 32, 33, 34
Common difference: +1 → Arithmetic

C. 11, 15, 17, 23

Differences: +4, +2, +6 → Not arithmetic

Explanation

• A. √16 = 4 → Rational

• B. √4 = 2 → Rational

• C. √9 = 3 → Rational

• D. √11 ≈ 3.316624... → Not a perfect square → Irrational

Correct answer: D. √11

Explanation

Micronutrients are essential elements required by organisms in small quantities for proper growth and development.

Among the options:

• Manganese, Iodine, Zinc, and Iron are all recognized micronutrients for humans and plants.

• Sodium, Magnesium, and Sulfur are considered macronutrients because they are required in larger amounts.

Explanation

 "Contemptuous" means showing deep hatred or disapproval, often with a sense of superiority.

A "contemptuous noise" would suggest a sound expressing scorn or disdain, not cheerfulness or humor.

Explanation

 A "legend" typically refers to someone who is extremely well-known and admired

 This aligns with the definition of "famous" rather than being merely a good, wise, or romantic person. 

Explanation

Ribose and Deoxyribose

Are isomers

• Both are monosaccharides (simple sugars) with the same molecular formula: C₅H₁₀O₅.

• Deoxyribose differs from ribose by one less oxygen atom at the 2' carbon (hence "deoxy").

• They are structural isomers (same formula, different structure).

Explanation

• a) Tuberculosis – Caused by the bacterium Mycobacterium tuberculosis 

• b) Typhoid – Caused by the bacterium Salmonella typhi 

• c) Cholera – Caused by the bacterium Vibrio cholerae 

• d) Influenza – Caused by the influenza virus (NOT a bacterium)