8th Class Geography MCQs | All Units & Do You Know Facts | PAKMCQs

Marine organisms are broadly classified into micro-organisms, plankton, benthos, fish, and mammals.

Micro-organisms in marine environments mostly include bacteria, as well as fungi and yeasts.

Plankton are small organisms found floating, suspended, or swimming in water bodies.

Benthos refers to the community of organisms living on, in, or near the ocean floor.

Wastes carrying toxic chemicals, heavy metals, and fertilizers first enter rivers and streams via drains and sewer systems before reaching the sea.

Industrial and agricultural byproducts introduce toxic heavy metals such as lead, mercury, cadmium, and chromium into water bodies.

The Saffir-Simpson Hurricane Wind Scale classifies hurricanes based on their sustained wind speeds.

Hurricane Katrina intensified into a Category 5 hurricane before causing catastrophic destruction in New Orleans.

Category 1 hurricanes have sustained winds of 74 to 95 mph (119 to 153 km/h).

A Category 2 hurricane carries wind speeds ranging between 96 and 110 mph (154–177 km/h).

Winds between 111 and 129 mph (178–208 km/h) define a Category 3 hurricane.

Category 4 hurricanes possess wind speeds of 130 to 156 mph (209 to 251 km/h).

Category 5 hurricanes sustain winds exceeding 157 mph (252 km/h).

Lightning heats the surrounding air instantly to about 54,000 °F (30,000 °C).

The extreme heating causes the air to expand explosively, producing a shockwave heard as thunder.

Rising atmospheric temperatures and climate changes are the result of 200 years of air pollution caused by burning fossil fuels.

Cumulonimbus clouds develop into spinning funnel clouds extending toward the ground to become tornadoes.

Inside a tornado, extremely low pressure generates violent updrafts of up to 240 km/h.

Harmful substances like smoke and ash are visible, whereas gases and radiation are invisible.

Worldwide plastic production in 1950 stood at approximately 1.5 million metric tons (about 1.7 million short tons).

By 2010, global plastic manufacturing surged to an estimated 275 million metric tons (about 303 million short tons).

Global plastic production reached 359 million metric tons (nearly 396 million short tons) in 2018.

Between 4.8 million and 12.7 million metric tons (5.3 to 14 million short tons) of plastic enter the oceans each year from coastal countries.

The Indus River Dolphin is a rare freshwater mammal whose existence is endangered due to rising river pollution.

Minamata disease is a severe neurological syndrome caused by mercury poisoning from consuming contaminated fish.

It was first discovered in Minamata city, Japan, where chemical industries discharged large quantities of mercury into the bay.

In 2017, the World Health Organization reported that 2.1 billion people globally lacked access to safely managed drinking water.

A 2019 WHO report highlighted that 785 million people worldwide lacked even basic drinking water services.

Light pollution affects ecosystems severely, mirroring the impacts of airborne pollutants such as carbon monoxide.

Hydroelectric power plants generate electricity using the energy of fast-flowing water released from dam reservoirs.

Solar panels convert light energy from the sun into electricity, which can be consumed immediately or stored in batteries.

Wind energy harnesses air movement to turn large windmills known as wind turbines to generate electricity.

In FY21, the industrial sector contributed 28.11% to Pakistan's total GDP.

Manufacturing constituted 12.52% of the GDP within the industrial sector in FY21.

The mining sub-sector accounted for 2.18% of the country's GDP in FY21.

Construction contributed 2.05% to the national GDP in FY21.

The electricity and gas sub-sector comprised 1.36% of the GDP in FY21.

Ginning refers to the industrial process of separating raw cotton fibers from the seeds.

Harvested and ginned cotton is compressed tightly into bales to facilitate transport.

Spinning is the mechanical process that draws and twists raw cotton fibers into yarn.

Weaving involves interlacing yarn threads to produce fabric or cloth.

Marine shipping accounts for approximately 90% of global international trade movements.

CPEC focuses on upgrading Pakistan's infrastructure through modern transportation networks and Special Economic Zones (SEZs).

The government aims to train and develop skilled domestic manpower to meet the long-term demands of CPEC.

The World Bank has officially replaced the term Gross National Product (GNP) with Gross National Income (GNI).

In 2022, Pakistan's unemployment rate stood at approximately 4.70%.

The United Nations classifies 36 nations across the globe as developed economies.

According to the United Nations, there are 156 developing countries in the world.