Post on 23-Feb-2016
description
.food chains &
food webs.ISN page 169.
• Food Chain
• Food Web
– Arrows?
• Producers
• Consumers
– Primary– Secondary– Tertiary
• Pyramid of Biomass
– Rule:
food chains & food webs 169
Food Chain• A simple diagram that
shows one part of an ecosystem.
• Transfer of energy from one organism to another
What is a food web?• Shows the
interactions of predators and prey in an ecosystem
What do the arrows indicate in a food web?
• They indicate the flow of energy from one organism to another.
• If a worm is eaten by a robin, does the arrow point to the worm or the robin?
• Producers make their food from the sun’s energy. They are also called autotrophs.
• Name 2 producers• Algae, bladderwrack
• Primary consumers eat producers. They are also called heterotrophs or herbivores.
• Name 3 primary consumers.• Grey mullet, flat winkle, limpet, sea urchin
• Secondary consumers eat primary consumers. They are also called carnivores.
• Name 3 secondary consumers.• Crab, seal, lobster, herring gull
• Tertiary consumers eat secondary consumers. • Are there any?• Yes…….seal, herring gull
Pyramid of Biomass• BIOMASS: how much
a population of organisms weighs
• The greatest amount of biomass is found in the producers.
• The least amount in the tertiary consumers.
10% Rule: Only 10% of the available energy passes on to the next trophic level
food chains & webs
Food Web Practice: 170• Identify the:• 1. Producers• • 2. Primary Consumers• • 3. Secondary Consumers• • 4. Herbivores• • 5. Carnivores• • 6. Omnivores• • 7. What elements are missing
from this food web?
1. What happens to matter within a food chains?2. What happens to energy within a food chain?3. In a pyramid of numbers, what would you not expect to find ?4. What is the carbon cycle?5. What is a niche? Give an example.6. What is an abiotic factor of an ecosystem?7. What are ecosystems based on?8. What do food producers need to make sugar?
ECOSYSTEMS NOTES