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

Explanation

• Globally, about 30% of food produced is lost or wasted before reaching consumers.
• This includes losses during harvesting, storage, transportation, and processing.

Additional information:

Food loss by stage:

• Harvesting – 10%
• Post-harvest handling – 5%
• Processing – 5%
• Distribution – 5%
• Retail & households – 5%

Last verified on 19-01-2026

Explanation

• Butterflies, moths, and honeybees help in transferring pollen from one flower to another, aiding in plant reproduction.
• They are essential for pollination of crops and wild plants.

Additional information:

• Pollination increases fruit and seed production.
• Honeybees are also important for honey production.

Last verified on 19-01-2026

Explanation

• Pakistan’s forest area is decreasing over the years due to deforestation, urbanization, and overgrazing.
• Forests cover about 5% of Pakistan’s total land area.

Additional information:

• Major forests: Himalayan, Indus plain, and mangrove forests.
• Government programs like tree plantations and protected areas aim to slow down deforestation.

Explanation

• The services sector is the largest contributor to Pakistan’s GDP.
• It accounting for around 58% of the total GDP.
• Agriculture contributes about 23%.
• Industry/manufacturing contributes around 20%.
  

Additional information:

• Services include finance, transport, education, health, and IT.
• Growth in services reflects urbanization and modernization of the economy.

Last verified on 19-01-2026

Explanation

Major sucking pests of cotton include:

• Whitefly – Causes leaf curling and transmits cotton leaf curl virus.
• Jassid (Leafhopper) – Sucks sap from leaves, causing yellowing.
• Aphid – Sucks plant sap and spreads viral diseases.

Additional information:

• Sucking pests reduce plant vigor and yield.
• Control methods: insecticides, biological control, and resistant varieties.

Last verified on 19-01-2026

Explanation

• Cereal crops are grown primarily for their edible grains.
• Examples: Wheat, Barley, Rice, Corn (Maize).

Additional information:

• Cotton: Fiber crop, not a cereal.
• Sugarcane: Cash crop, grown for sugar production.
• Cereal crops are staple foods and form a major part of the human diet.

Last verified on 19-02-2026

Explanation

• Strip cropping involves planting different crops in alternate strips along the contour of the land.
• It helps in reducing soil erosion by slowing water runoff and protecting soil.

Additional information:

• Monocropping: Growing a single crop continuously – increases soil erosion risk.
• Shifting cultivation: Clearing new land each season – also leads to erosion.
• Example: Alternating strips of maize and legumes on slopes.

Last verified on 19-01-2026

Explanation