Chapter 10 Learning Review

Carbon Cycle

1) atmosphere CO₂ enters biosphere thru photosynthesis 2) some of CO₂ is consumed directly thru plant respiration 3) plant growth is dependent on a surplus of carbohydrate production

Oxygen Cycle

1) most of the oxygen in the atmosphere is through photosynthesis 2) through ozone, oxygen stored in and sometimes released from carbonized rocks 3) some that are human induced- burning fossil fuels

What is the importance of photosynthesis to the flow of energy, water, oxygen, and carbon through the biosphere?

1) solar energy becomes fixated in the biosphere via photosynthesis by green plants 2) green plants take CO₂ from air, combine water, to create carbohydrates 3) with plant respiration, stored energy is oxidized by plant, releasing CO₂, H₂O and heat energy

limiting factor

A term often to describe the variable that is most important in determining the survival of an organism.

interspecific competition

Competition among members of different species. Example: land- animals on land

intraspecific competition

Competition among members of the same species. Example: a oak tree bending to get sunlight

plant respiration

Consumption of carbohydrates by plants

nitrogen fixation

Conversion of gaseous nitrogen into forms that can be used by plants (nitrates)

denitrification

Conversion of nitrates back into the gaseous form.

Why are trees in dense forests likely to be tall with narrow tops?

Light has a significant effect on plant shape. Where light is restricted, trees are more likely to be very tall but have limited lateral growth.

Why is it difficult to integrate nitrogen gas from the atmosphere into the nitrogen cycle of the biosphere?

Only a limited number of organisms (nitrogen-fixing bacteria living in soil) can use nitrogen in its gaseous form.

Explain how both photosynthesis and photoperiodism are dependent on sunlight.

Photosynthesis is activated by light. Photoperiodism affects photosynthesis and how much light an organism receives during any 24 hour period.

photosynthesis

Process where plants produce chemical energy from water, carbon dioxide, and is activated by sunlight.

What is the primary source of carbon that humans have added to the atmosphere?

Release of fossil fuels through burning.

What is the primary source of energy for the biosphere?

Solar Energy is the primary source for all life on Earth.

edaphic factors

soil characteristics; this factor's influence on plants is direct and indirect on animals.