Chapter 4. Ecosystems. Standard 2: Students know and understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. . Concepts and Skills to Master:
Standard 2: Students know and understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment.
Abiotic factor algal bloom
Biomass biotic factor
Food web herbivore
Omnivore trophic level
Pyramid of biomass pyramid of energy
Pyramid of numbers
First-order consumers Video: approx. 60 min
Biotic Factor is the relationship between living things (3:57)
The interaction of a community with its environment is an ecological system also called an ecosystem.
Due to changes in an ecosystem like volcanoes, floods or drought opportunities arise for different organisms to replace existing ones in a single place over time in a process called succession.
First where there was bare ground, pioneer species will grow, then be replaced by grasses and shrubs, then eventually trees.
A biome is a large region characterized by a specific kind of climate and certain kinds of plant and animal communities.
Climate is the average weather conditions over a long period of time in a specific area.
Two key factors that determine the types of biomes that exist are temperature and precipitation.
Major terrestrial biomes can be grouped by latitude into:
Tropical (at the equator)
Temperate (Mid latitudes)
High Latitude (Cold temperatures)
Freshwater (bodies of fresh water—rivers, lakes ponds)
Wetlands (link between land and fully aquatic habitats)
Estuaries (where river and ocean meet)
Marine (fully aquatic, salty waters of the oceans)ss
Virtual Investigation (DVD) on Ecosystems and Energy pyramids.
Marine trophic level
Marine Food Web (2:10)
The transfer of energy within an ecosystem is called the pyramid of energy.
Energy originally produced is not lost, just changed into different forms of energy such as heat.
Energy can also be stored—more than ½ of the potential energy in each food molecule is lost as heat energy during cellular respiration.
The pyramid of numbers does not apply to all food chains. An exception would be where a large organism is fed upon by smaller ones. Example: a dog infested with parasites.
Whaleshark and remora
Bee and flower
Indian paintbrush and bluebonnet
Abiotic Factors are the relationship between non-living things.
Hazel dormouse hibernating in burrow
Temperature can also affect metabolic rate (activity of enzymes). Organisms cannot survive above 50oC because enzymes are destroyed.
Lizards compensate for desert heat by shading up during the day while some frogs go dormant.
Summer dormancy is called estivation.