Lesson 4: Interaction

Lesson 4: Interaction

Activity 1

pp. 322-324

Activity 2

Food Web vs.Food Chain

Activity 3

pp. 331-32

The water cycle shows the continuous movement of water within the Earth and atmosphere.

It is a complex system that includes many different processes.

Liquid water evaporates into water vapor, condenses to form clouds, and precipitates back to earth in the form of rain and snow.

Carbon and Oxygen Cycle

They act separately but are dependent on each other because the carbon cycle gives off oxygen for the oxygen cycle to use, and in turn, the oxygen cycle emits carbon dioxide (CO₂) which goes back into the carbon cycle. Plants are the main vehicle by which the oxygen and carbon cycles are connected

The nitrogen cycle describes how nitrogen moves between plants, animals, bacteria, the atmosphere (the air), and soil in the ground. Nitrogen is an important element to all life on Earth. Different Nitrogen States For Nitrogen to be used by different life forms on Earth, it must change into different states. Nitrogen in the atmosphere, or air, is N2. Other important states of nitrogen include Nitrates (N03), Nitrites (NO2), and Ammonium (NH4).

Processes in the Nitrogen Cycle

1. Fixation - Fixation is the first step in the process of making nitrogen usable by plants. Here bacteria change nitrogen into ammonium.

2. Nitrification - This is the process by which ammonium gets changed into nitrates by bacteria. Nitrates are what the plants can then absorb.

Processes in the Nitrogen Cycle

3. Assimilation - This is how plants get nitrogen. They absorb nitrates from the soil into their roots. Then the nitrogen gets used in amino acids, nucleic acids, and chlorophyll.

4. Ammonification - This is part of the decaying process. When a plant or animal dies, decomposers like fungi and bacteria turn the nitrogen back into ammonium so it can reenter the nitrogen cycle. Denitrification - Extra nitrogen in the soil gets put back out into the air. There are special bacteria that perform this task as well.

Why is nitrogen important to life?

Plants and animals could not live without nitrogen. It is an important part of many cells and processes such as amino acids, proteins, and even our DNA. It is also needed to make chlorophyll in plants, which plants use in photosynthesis to make their food and energy.

Multiple Choice

How are primary consumers different from secondary consumers?

• Primary consumers eat only plants; secondary consumers eat other consumers.

• Primary consumers eat other consumers; secondary consumers eat only plants.

• Primary consumers eat plants and other consumers; secondary consumers eat plants and decompose matter.

• Primary consumers eat plants and decompose matter; secondary consumers eat plants and other consumers.

Multiple Choice

How might a lack of sunlight disrupt the food web?

• It would cause consumers to consume less.

• It would prevent decomposers from decomposing matter

• It would prevent producers from producing nutrients.

• It would not disrupt the food web at all.

Multiple Choice

Through what process do producers make their own food?

• Parthenogenesis

• Photosynthesis

• Meiosis

• Mitosis

Multiple Choice

What can you infer from the fact that the disappearance of just one species can disrupt an entire food chain?

• Every food chain depends entirely on a single species

• Food chains are extremely fragile

• Food chains can regenerate on their own

• Food chains would not exist without humans

Multiple Choice

How is a food web different from a food chain?

• Food webs contain only producers, not consumers.

• Food webs do not include decomposers.

• Food webs contain many different, linked food chains.

• Food webs exist in aquatic environments; food chains exist in terrestrial environments.

Multiple Choice

Where an animal lives is called the animal's ______

• wildlife
• habitat
• environment 
• carnivore 

Multiple Choice

An organism that lives by breaking apart dead organic matter into simpler parts is...

• scavenger
• consumer
• decomposer
• carnivore

Multiple Choice

The way energy is passed from one organism to another

• food chain

• energy

• extinct

• habitat

Multiple Choice

The way energy is passed from one organism to another

• food chain

• energy

• extinct

• habitat

Multiple Choice

After condensation, the droplets of water in the clouds fall to Earth in different forms...

• precipitation

• condensation

• evaporation

Multiple Choice

What part of the water cycle does this picture show?

• condensation
• precipitation
• evaporation

Multiple Choice

What do humans get after a plant goes through photosynthesis?

• Oxygen
• Sodium
• Sodium chloride

Multiple Choice

A gas produced by animals during respiration that plants use for photosynthesis.

• Oxygen
• Carbon Dioxide
• Photosynthesis
• Radiation

Multiple Choice

A gas produced by plants during photosynthesis that animals use for respiration.

• Oxygen
• Carbon Dioxide
• Methane
• Sulphur

Multiple Choice

The movement of carbon dioxide and oxygen on Earth by the processes of respiration and photosynthesis.

• Carbon Dioxide-Oxygen Cycle
• Oxygen
• Carbon Dioxide
• Respiration

Multiple Choice

The total amount of the carbon on Earth is constant.

• True

• False

Multiple Choice

Which one of these does not add CO2 to the atmosphere?

• cooking with gas
• planting trees
• burning wood
• riding in a bus

Multiple Choice

In what process is Carbon transformed into chemical energy?

• Photosynthesis
• Respiration
• Primary Production
• Secondary Production

Multiple Choice

How much of the atmosphere is composed of nitrogen gas?

• 87%
• 38%
• 78%
• 21%

Multiple Choice

Organism that breaks down dead plants & animals and releases nitrogen back into atmosphere

• bacteria
• plants
• animals
• producers

Multiple Choice

How do plants get the nitrogen they need?

• from the air

• from the soil or water in which they live

• from the Sun

• from broken-down rocks

Multiple Choice

How do plants get the nitrogen they need?

• from the air

• from the soil or water in which they live

• from the Sun

• from broken-down rocks