Nutrient Cycles and Global Warming

Question 0

What is ammonification

Answer 0

The nitrogen gas is in pairs, they do not want to separated easily. Nitrogen combines with oxygen due to lightning to form nitrogen oxide. Saprobiotic microorganisms feed on dead material and waste to release ammonia which forms ammonium ions

Question 1

What are saprobiotic microorganisms and what do they do

Answer 1

Decomposers, they feed on dead material and waste, releasing ammonia which forms ammonium ions

Question 2

Ammonium ions are oxidised to….

Answer 2

Nitrite ions

Question 3

Nitrite ions are oxidised to….

Answer 3

Nitrate ions

Question 4

Nitrate ions are….

Answer 4

Reactive

Question 5

What is nitrification

Answer 5

This is carried out by free-living soil microorganisms called nitrifying bacteria. Ammonium ions oxidised to nitrite ions by nitrosomonas bacteria,these oxidised to nitrate ions (which are reactive) by nitrobacter bacteria.

Question 6

What is nitrogen fixation

Answer 6

Nitrogen gas converted into nitrogen containing compounds by….
free living nitrogen fixing bacteria, which reduce gaseous nitrogen to ammonia and amino acids

Mutualistic nitrogen-fixing bacteria, called Rhizobium, live in nodules on roots of plants, obtain carbohydrates from plant, turn into amino acids

If there is plenty of oxygen in the soil then these products enter the plants by active transport

Question 7

What is denitrification

Answer 7

Soils are waterlogged and lack oxygen. Fewer nitrifying and nitrogen fixing bacteria= increase in anaerobic denitrifying soil nitrates. Gaseous nitrogen produced. Decrease in availability of nitrogen containing compounds. Soils need to be aerated through ploughing

Question 8

What else can cause the nitrogen cycle to occur

Answer 8

Industry

Lightning

Question 9

What are the 4 major processes involved in the carbon cycle

Answer 9

Photosynthesis

Respiration

Decomposition

Combustion

Question 10

Why do respiration and photosynthesis cause fluctuations in CO2 conc

Answer 10

Respiration adds CO2 atmosphere, photosynthesis removes CO2. Both of these vary on a daily and yearly basis causing fluctuations

Question 11

What is the greenhouse effect

Answer 11

Effect of greenhouse gases absorbing outgoing energy so that less is lost to space

Question 12

3 main greenhouse gases

Answer 12

CO2

Water vapour

Methane

Question 13

Human activities like ……………… have increased atmospheric concs of CO2 and methane

Answer 13

Burning fossil fuels

Farming

Deforestation

Question 14

How could global warming affect crop yield

Answer 14

Increasing CO2 conc= increase in crop yield. CO2 is a limiting factor of photosynthesis so increasing concs means crops grow faster, increasing yields

Question 15

How could global warming affect insect pests

Answer 15

Can affect life cycle of some insect pests. Eg global warming means some insect pests go through their larval stage quicker and emerge a adults earlier. Global warming can also affect numbers of insect species…. Some becoming more abundant (warmer wetter summers have led to increase in Mosquitos), others less abundant (some tropical insect species can only thrive in specific temp ranges so if it gets too hot fewer insects can reproduce successfully)

Question 16

How could global warming affect wild animals and plants

Answer 16

Can affect distribution, some become more widely distributed (species need warmer temps may spread further as conditions they thrive in exist over bigger area), others less distributed

Can also affect numbers, some become more abundant, others less

Question 17

The nitrogen cycle shows…

Answer 17

How nitrogen is converted into a useable form and then passed on between different living organisms and the non-living environment

Question 18

What is leaching

Answer 18

When water soluble compounds in soil are washed away, often into nearby ponds and rivers. If nitrogen fertiliser is leached into waterways can cause eutrophication