Question

3 multiple choice 20 points
why is the carbon/oxygen cycle important for ecosystems? (dok 2)
it moves carbon and oxygen through living organisms and the environment, helping maintain balance through photosynthesis and cellular respiration.
it removes water from the soil, increasing the speed of the water cycle so that all living organisms have greater access to fresh water.
it provides energy directly to animals, which allows animals to then provide energy to plants. this helps prevent the loss of energy through transfer.
it causes plant to grow more efficiently, providing more food to all other living things. this allows the biosphere to be rich in both carbon and oxygen.
4 multiple choice 20 points
what can happen to biodiversity in an ecosystem if the carrying capacity is exceeded. (dok 2)
biodiversity will increase indefinitely because as a population reaches its carrying capacity, other populations increase to accommodate the growth.
more species will be born without any problems because while there is a limited amount of space on earth, energy is unlimited because of the sun.
some species may die or move away because there are not enough resources.
carrying capacity has no effect on biodiversity.

Explanation:

For question 3:

• The carbon/oxygen cycle involves photosynthesis (carbon dioxide taken in, oxygen released) and cellular respiration (oxygen taken in, carbon dioxide released). It moves carbon and oxygen between organisms and the environment, maintaining balance.
• The second option is about the water cycle.
• The third option is incorrect as plants get energy from the sun (via photosynthesis), not from animals.
• The fourth option is not a correct description of the carbon/oxygen cycle's main importance.

For question 4:

• Carrying capacity is the maximum number of organisms an ecosystem can support.
• If exceeded, resources (food, water, space) become limited.
• The first option is wrong as biodiversity doesn't increase indefinitely when carrying capacity is exceeded.
• The second option is incorrect as energy is not unlimited in a practical sense for an ecosystem's organisms (e.g., competition for sunlight - limited in some habitats).
• The fourth option is wrong as carrying capacity directly affects biodiversity (through resource availability).

Answer:

1. It moves carbon and oxygen through living organisms and the environment, helping maintain balance through photosynthesis and cellular respiration.
2. Some species may die or move away because there are not enough resources.