Nitrogen Cycle Quiz

What is the most abundant gas in the atmosphere?

• Hydrogen

• Nitrogen

• Carbon dioxide

• Oxygen

Which organisms can convert nitrogen gas into ammonia?

• Fungi

• Plants

• Animals

• Bacteria

What is the process called when lightning transforms nitrogen in the atmosphere into NO3?

• Ammonification

• Denitrification

• Nitrification

• Nitrogen fixation

What is the main function of nitrogen-fixing bacteria in root nodules of leguminous plants?

• Produce energy for the plant

• Produce glucose for the plant

• Absorb nitrates for the plant

• Fix atmospheric nitrogen into ammonium ions

What do nitrifying bacteria in the soil convert ammonium ions into?

• Ammonia

• Nitrites

• Nitrates

• Proteins

How is nitrogen returned to the atmosphere by denitrifying bacteria?

• By converting nitrates into ammonia

• By releasing nitrogen gas as a by-product

• By converting ammonia into nitrates

• By absorbing nitrogen from the atmosphere

Why are waterlogged soils not good for farmers?

• Because they promote the growth of nitrifying bacteria

• Because they promote the growth of nitrogen-fixing bacteria

• Because they increase the quantity of nitrates available for crop growth

• Because they reduce the quantity of nitrates available for crop growth

What causes the breakdown of organic matter to be higher in tropical forests than in temperate woodlands?

• Higher levels of oxygen in tropical forests

• Higher levels of nitrogen in tropical forests

• Higher temperatures and year-round availability of water in tropical forests

• Higher levels of carbon dioxide in tropical forests

What is the main advantage of rapid recycling of nitrogen in tropical forests compared to temperate forests?

• More rapid growth of decomposers

• Higher levels of carbon dioxide in the atmosphere

• Higher levels of oxygen in the atmosphere

• More rapid growth of plants

What is the process called when lightning transforms nitrogen in the atmosphere into NO3?

• Ammonification

• Denitrification

• Nitrification

• Nitrogen fixation