Biology 2 Flashcards
What does a pyramid of biomass show? (2)
A pyramid of biomass shows the dry mass of organisms (1) at each trophic level (1).
Explain why the pyramid of biomass for a food chain could be different than the pyramid of numbers. (2)
The pyramid of numbers would be irregular since one ____________ can feed many ___________ (1). It also does not take into account the size of each organism in the food chain, unlike the pyramid of biomass (1).
What is the process occurring in cows that generates heat? (1)
Respiration (1)
Farmers often try to reduce the energy lost from cows.
Suggests how they can do this. (2)
Keep in warm conditions (1) Restrict movement (1)
Farmers often try to reduce the energy lost from cows.
Suggest why they want to do this. (1)
More energy for growth (1)
Animals called corals live in many oceans. The carbon in coral is recycled over many years. Explain how this occurs. (3)
The dead remains of corals fossilise to become limestone (1). The limestone is weathered over time (1). A chemical reaction occurs which releases carbon dioxide into the atmosphere (1).
Nitrogen gas in the air is unreactive. Describe how it can be converted into a form that can be used by plants. (4)
Lightening provides energy for nitrogen and oxygen in the air to combine (1). Nitrogen oxides dissolve in rain water which releases nitrates into the soil (1).
Nitrogen-fixing bacteria convert atmospheric nitrogen (1) into nitrates in the soil (1).
Black bears and polar bears both live in Canada. Both types of bears spend the winter months buried in holes or dens. Explain why. (3)
Hibernate (1) to conserve food supplies (1) since less food is available in the winter (1).
Cactus plants have spines instead of leaves. Explain why. (2)
Spines protect water supply from predators (1) and reduce water loss via leaves (1).
Lizards stay out in the Sun before hunting. Explain why. (2)
Absorb heat from the Sun (1) to warm up (1).
Why is Lamarck’s theory of evolution considered incorrect by most scientists now? (3)
No genetic basis (1); genes cannot be altered during organisms’ lifetime (1). Acquired characteristics cannot be inherited (1).
Suggests two effects the increasing world population will have on the environment. (2)
Cause global warming (1) which will result in rising sea levels, floods and droughts (1).
In underdeveloped countries the population may be higher than in developed countries, yet they cause less pollution. Suggest why. (3)
More industrial activity, (1) travel (1) and less local food eaten (1).
Suggests two reasons why saving pandas might help people who live in the same habitat. (2)
Employment and money from tourism (1) and better transportation (1).
Explain the problems of achieving sustainable development with a rising world population. (3)
Difficult to dispose of increased waste without causing pollution (1). More food in demand which results in habitat destruction (1). Increased demand for energy which means fossil fuels burned (1).
