Ecology Exam Notes

Types of Consumers

• Herbivores: Plant eaters (e.g., cow, grasshopper, deer).
• Carnivores: Meat eaters (e.g., lion, hawk, snake).
• Omnivores: Eat both plants and meat (e.g., humans, bears, raccoons).

Decomposers

• Decomposers break down dead material and waste.
• This process releases nutrients back into the soil, aiding plant growth and continuing the cycle of life.

Scavengers

• Scavengers eat dead animals instead of hunting live ones or eating plants.

Herbivore

• Primary consumer

Food Chain

• Trophic Levels: Level 1 (grass), Level 2 (grasshopper), Level 3 (frog), Level 4 (snake), Level 5 (hawk).
• Producer: Grass.
• Herbivore: Grasshopper.
• Carnivores: Frogs, snake, hawk.
• Autotroph: Grass.
• Heterotrophs: Grasshopper, frogs, snake, hawk.
• Primary Consumer: Grasshopper.
• Secondary Consumer: Frog.
• Tertiary Consumer: Snake.
• Quaternary Consumer: Hawk.
• Impact of Increased Frog Population: Grasshopper population decreases due to increased predation.
• Impact of Increased Hawk Population: Snake population decreases due to increased predation.

Ecology

• Hydrosphere: The water portion of Earth.
• Lithosphere: The solid, rocky outer layer of Earth.
• Atmosphere: The gas portion extending over 500 km from Earth's surface.

Abiotic vs. Biotic Factors

• Abiotic Factors: Non-living physical and chemical elements (e.g., temperature, sunlight).
• Biotic Factors: Living parts of an ecosystem that interact (e.g., plants, animals).

Producers

• Definition: Living things that create their own food using sunlight.

Consumers

• Definition: Living things that eat other living things for energy because they cannot make their own food.
• Types: Herbivores (eat plants), carnivores (eat animals), omnivores (eat both).

Photosynthesis

• Word Equation: Carbon Dioxide + Water + Sunlight $\rightarrow$ Glucose + Oxygen.
• Performed by: Producers only (e.g., plants and algae).

Cellular Respiration

• Word Equation: Glucose + Oxygen $\rightarrow$ Carbon Dioxide + Water + Energy.
• Performed by: Both consumers and producers.

Biodiversity

• Definition: Variety of all living things in an ecosystem.
  • Different species of animals, plants, fungi, and microorganisms.
  • The genetic differences within those species.
  • The ecosystems they form (forests, oceans, or deserts).

Food Web

• Example: Grass $\rightarrow$ Grasshopper $\rightarrow$ Mouse/Praying Mantis $\rightarrow$ Snake $\rightarrow$ Hawk
• Impact of Hawk Extinction:
  • Snakes and mice populations increase.
  • Possible overfeeding leading to fewer grasshoppers and grass.
  • Imbalance in the food web affecting other species.
• Organism with Most Energy: Grass, as it is a producer. Energy originates from the sun.

Static Electricity

• The build-up of electric charges on the surface of an object.

Current Electricity

• The movement of electric charges through an object.

Moving Particle in a Circuit

• Electrons.
• Flow from negative to positive.

Theory of Electrical Charges

• Explains how objects gain or lose electric charge and how these charges interact.

Charging Methods

• Friction: Transfers electrons through rubbing.
• Contact: Transfers charge by touching.
• Induction: Moves electrons using an electric field without physical contact.