Introduction to Ecology

Objectives: I will be able discuss the interdependence of biotic and abiotic factors. I will be able to discuss the laws of thermodynamics.

Ecology Defined Ecology is the study of interactions between organisms and their environment.

Abiotic vs. Biotic Factors The environment includes 2 types of factors: 1.Abiotic factors – the nonliving parts of the environment. Examples: water, oxygen, light, temperature, rocks, minerals, energy 1.Biotic factors – the living parts of the environment. Examples: plants, animals, bacteria, fungi, and protists

The Laws of Thermodynamics The First Law of Thermodynamics states that energy (or matter) cannot be created or destroyed, but can change forms. The Second Law of Thermodynamics states that every energy transfer increases the entropy (amount of disorder or randomness) = some energy becomes unusable. In biology entropy is usually referred to as heat. Closed systems allow energy to enter but matter cannot enter or leave; closed systems are rare in biology. Each time energy or matter “changes form” energy is conserved but the internal energy of a closed system changes as heat is transferred in or out of it.

Abiotic and Biotic Interactions

Levels of Organization Arrange the following terms from the smallest to the largest: Population Cell Organ System Tissue Molecule Ecosystem Community Organism Organ Biosphere

Levels of Organization 8

Population – a group of organisms of the same species that live together in a certain area. Community – a group of populations of different species living close enough to interact. Ecosystem – all living and nonliving components in a certain area. Biosphere – the entire portion of the planet that supports life.

Review Vocabulary Habitat = Place where an organism lives. What is the habitat of a mushroom? Niche = Ecological role and space that an organisms fills in the environment (the way of life of a species). What is the niche of a sunflower?

MATH CONNECTION The biomass (biological material from living or recently living organisms) of a deciduous forest is 50% carbon. Additionally, the biomass increases annually at a rate of 2.7 x 10 5 kg/hectare. Calculate the mass of carbon accumulated and stored in 1.0 hectare of this forest in one year. Give your answer to the nearest hundredth of 10 5 kg. Note: 1 hectare = 10,000 square meters or 2.5 acres

Summary: In your own words, paraphrase key points of the lesson. Focus on the concepts you do not understand well; thinking and writing will help you master them. You need to have a minimum of five sentences. Example of a good summary sentence: “There are biotic/living components in environments, such as organisms, and many abiotic/non-living components, such as water and rocks”. Example of a terrible summary sentence: “Today I learned about laws of thermodynamics.” This sentence only lists the topic and does not show what you know. Please never start with “Today I learned about…” Instead, dive into the explanations right away. There is no space for introductory sentences in your summary sections of notes.