Explanation

• Seeds with a short storage period lose their viability quickly.
• Such seeds can generally be stored for about 1–2 months under normal conditions.

Additional information:

Storage life of seeds:

• Short-lived seeds – 1–2 months
• Medium-lived seeds – 3–8 months
• Long-lived seeds – 9–12 months or more
• Onion seeds – short storage life
• Lettuce seeds – short storage life

Last verified on 19-02-2026

Explanation

• The Paris Peace Agreement was signed in 1973 to end the Vietnam War.
• It aimed to establish peace and end U.S. military involvement in Vietnam.

Additional information:

• Agreement signed: 27 January 1973
• War involved mainly: North Vietnam, South Vietnam, USA
• Duration of Vietnam War: 1955–1975
• U.S. troops withdrawal began in 1973
• Fall of Saigon: 1975

Last verified on 19-01-2026

Explanation

• Meristematic cells are undifferentiated cells capable of continuous division.
• They are responsible for the growth of plants in length and thickness.

Additional information:

Types of meristems:

• Apical meristem – root & shoot tips
• Intercalary meristem – nodes & internodes
• Lateral meristem – increase in girth
• Root meristem – root growth
• Shoot meristem – shoot growth

Last verified on 19-01-2026

Explanation

• In plants, carbohydrates are stored mainly in the form of starch.
• Starch serves as an energy reserve used during growth and development.

Additional information:

Storage forms in plants:

• Starch – main carbohydrate reserve
• Sucrose – transport form of carbohydrate
• Cellulose – structural carbohydrate
• Glycogen – storage carbohydrate in animals
• Glucose – immediate energy source

Last verified on 19-01-2026

Explanation

• Residual phenolics are chemical compounds in plants or soil that remain active for a period of 2 to 5 months.
• They help in protecting plants against pests and diseases.

Additional information:

Duration of residual effects in common substances:

• Phenolics – 2 to 5 months
• Organophosphates – 1 to 2 months
• Carbamates – 1 month
• Pyrethroids – 3 months
• Neonicotinoids – 4 to 5 months

Last verified on 19-01-2026

Explanation

• Comets are small celestial bodies made of ice, dust, and rock.
• When they approach the Sun, they form bright tails of gas and dust.

• Often called “dirty snowballs” due to icy composition.
• Comets follow highly elliptical orbits around the Sun.

Last verified on 19-01-2026

Explanation

• Faustin Elmer Chaudhary, popularly known as “Chacha”.
• He was a pioneering photographer and photojournalist in Pakistan.
• Known as the father of news photography in Pakistan.

Additional information:

Major contributions:

• 1947 Partition – documented events as the only local photographer
• 1940 Muslim League Session in Lahore
• Visits of Quaid-e-Azam Muhammad Ali Jinnah
• Worked at The Pakistan Times from 1949 to 1973
• Received awards: Pride of Performance, Sitara-i-Imtiaz, Tamgha-i-Khidmat

Last verified on 19-01-2026

Explanation

• DNA (Deoxyribonucleic Acid) contains the sugar deoxyribose, which is a five-carbon sugar.
• It forms the backbone of the DNA molecule along with phosphate groups.

Additional information:

• Sugars in nucleic acids:
• DNA – Deoxyribose
• RNA – Ribose
• Glucose – energy source in cells
• Fructose – sugar in fruits
• Galactose – sugar in milk

Last verified on 19-01-2026

Explanation

• Unisexual flowers have either male (staminate) or female (pistillate) reproductive organs, but not both.
• They are important in plants that rely on cross-pollination.

Additional information:

Examples of unisexual plants:

• Papaya (Carica papaya) – male and female flowers separate
• Cucumber (Cucumis sativus) – male and female flowers
• Maize (Zea mays) – tassel (male) & cob (female)
• Date palm – male and female trees
• Ginkgo – separate male and female trees

Last verified on 19-01-2026

Explanation

• Price discrimination occurs when the same product is sold at different prices to different customers.
• It is a common practice in markets to maximize profits based on customer willingness to pay.

Additional information:

Types of price discrimination:

• First-degree – individual pricing
• Second-degree – bulk or quantity discounts
• Third-degree – group-based pricing (students, seniors)
• Airline tickets – different prices for same seat on same flight
• Movie tickets – matinee vs. evening pricing

Last verified on 19-01-2026