Transcript Unit 14
Unit 4 Section 1 Ecology Biosphere • All life on Earth and all parts of the Earth where life exists – Includes land, water and atmosphere Ecology • Ecology – the scientific study of the interactions between organisms and their physical environment. – Environment – all conditions or factors surrounding an organism. – Environment includes two main types of factors: • Biotic factors – living factors in the environment – Example: fish, snails, algae and plants • Abiotic factors – non-living factors in the environment – Example: water, gravel, temperature, light Energy, Producers and consumers • Energy is needed for growth, reproduction and all processes in the body – Without energy we cannot live!!! • Where does all energy on Earth come from? – The sun!!! – Only certain organisms can capture energy from the sun and convert it into a form they can use • These include algae, certain bacteria and plants • Energy is converted into a form living cells can use Primary Producers • These organisms are called autotrophs or primary producers because they can make their own food using light energy from the sun and are the first producers of energy rich compounds other organisms need to survive – Use energy from sun to convert inorganic compounds into organic molecules (sugar) – Organisms that eat autotrophs then use energy stored in the bonds of these organic molecules – Without autotrophs there would be no energy or food for organisms on the planet!!!!! Remember Photosynthesis?? Can there be life without light? • Yes! • About 30 years ago scientists found ecosystems around deep ocean vents where it is very dark. • These organisms use a process called chemosynthesis to harness energy from inorganic molecules instead of photosynthesis since there is no light Consumers • Heterotrophs – cannot capture light energy from the sun – Must get energy from other organisms by consuming them – That is why they are also called consumers! – There are several different types of consumers depending on what they eat! Types of Consumers • Herbivore – eat plant leaves, roots, seeds, fruits – Examples: cow, caterpillars, deer • Carnivore – kill and eat other animals – Examples: snakes, dogs, cats, river otter • Omnivores – eat both plants and animals – Examples: humans, bears, pigs • Scavengers – eat carcasses of other animals that have been killed by predators or have died of natural causes – Example: vultures Types of Consumers • Decomposers – feed by chemically breaking down organic matter (dead plants and animals) – Produces detritus: small pieces of decaying plants and animals – Example: Bacteria and fungus • Detritivores – chew or grind up detritus particles into smaller pieces – Examples: mites, shrimp, snails and crabs