JMEMS Unit 3A Ecosystem

In the process of photosynthesis, sunlight is converted into

• Chemical Energy

• Mechanical Energy

• Nuclear Energy

• Kinetic Energy

A plant can take in carbon dioxide gas (CO2 ) and water (H2O) and convert it into sugar. This process requires an energy input because the sugar that is formed has more energy than the carbon dioxide and water from which it was made.

Which explains how this is possible?

• Plants convert light energy from the Sun into the chemical energy necessary to make the sugars.

• Plants absorb heat energy from the Sun and soil for the energy necessary to make the sugars.

• Plants absorb chemicals through their roots for the energy necessary to make the sugars.

• Plants convert mechanical energy into chemical energy to make the sugars.

Elodea is a plant that grows under water. Martina used pieces of Elodea in test tubes of water to conduct an experiment. Her results are shown in the table below.

What question was she most likely trying to answer?

• How does light intensity affect the rate of photosynthesis in plant leaves?

• How does light intensity affect the rate of cellular respiration in plant leaves?

• How does light intensity affect the amount of water produced by plant leaves?

• How does light intensity affect the amount of oxygen absorbed by plant leaves?

The diagram illustrates plants and two different zones of a deep lake.

In the upper part of the photic zone, organisms carry out both photosynthesis and cellular respiration. Deep in the aphotic zone, only cellular respiration occurs.

Which statement is the most likely reason photosynthesis does not occur in the deepest aphotic zone?

• Sunlight for photosynthesis does not reach the deepest aphotic zone.

• Water pressure limits the survival of animals in the deepest aphotic zone.

• Not enough soil is present to support plant growth in the deepest aphotic zone

• Not as much dissolved oxygen from the surface reaches the deepest aphotic zone.

The table compares two cellular processes.

Based on the information in the table, which two processes are being compared?

• growth and reproduction

• osmosis and diffusion

• decomposition and fermentation

• photosynthesis and respiration

Monty was learning about life in the ocean. He made a food chain of some of the organisms he was studying.

Which organism can change energy from the Sun into a form that is usable by other organisms?

• ALGAE

  similar to seaweed

• KRILL

  small Shrimp

• HERRING

  Fish

• GULL

  Bird

The diagram shows a process that takes place in plant cells.

Which process is best shown by the diagram?

• photosynthesis

• reproduction

• respiration

• transport

Ann is drawing a model of what happens when a person eats an apple.

Which statement best describes the next step in Ann’s model?

• Sugar molecules break down further to release energy inside of cells.

• Sugar molecules combine chemically to absorb energy made by cells.

• Sugar molecules break down further to release oxygen for use by cells.

• Sugar molecules combine with other molecules to absorb waste material from cells.

Which two things are produced when a plant breaks down sugar to release energy?

• carbon dioxide and water

• oxygen and carbon dioxide

• carbon dioxide and food

• oxygen and food

What is the relationship between mass and solar energy in plants?

• Plants increase in mass as they convert solar energy to chemical energy.

• Plants increase in mass as they convert solar energy to thermal energy.

• Plants decrease in mass as they convert solar energy to chemical energy.

• Plants decrease in mass as they convert solar energy to thermal energy.