Chapter 1.3

Question 1

How do biotic factors influence species in an ecosystem?

Answer 1

They affect population size, competition, predator-prey relationships, and symbiotic interactions.

Question 2

What are some examples of biotic interactions?

Answer 2

• Competition (for food, water, space)
• Pollination (bees pollinating flowers)
• Predation (wolves hunting deer)

Question 3

What are trophic levels and how does energy flow between them?

Answer 3

• Hierarchical levels in a food chain, representing the flow of energy from one organism to another in an ecosystem* Producers → Primary Consumers → Secondary Consumers → Tertiary Consumers
• Energy decreases at each level due to heat loss.

Question 4

Why does only 10% of energy transfer to the next trophic level?

Answer 4

Energy is lost as heat, through respiration, movement, and waste.

Question 5

What is the difference between a food chain and a food web?

Answer 5

• Food Chain: A linear sequence of energy transfer.
• Food Web: A complex network of interconnected food chains.

Question 6

What is photosynthesis? Write the word and chemical equation.

Answer 6

• Definition: Process by which plants convert sunlight into energy.
• Word Equation: Carbon dioxide + Water → Glucose + Oxygen
• Chemical Equation: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

Question 7

What part of the plant cell captures light energy for photosynthesis?

Answer 7

Chloroplasts (contain chlorophyll).

Question 8

What is a limiting factor in photosynthesis?

Answer 8

A condition that restricts the rate of photosynthesis, such as light availability, carbon dioxide concentration, or water supply.