Biology Lecture Notes Cheat Sheet

Ecosystem a biological community of interacting organisms in conjunction with the abiotic components of their physical environment, interacting as a system first law of thermodynamics Energy cannot be created or destroyed- it can only change from one form to another law of conservation of mass Matter cannot be created or destroyed second law of thermodynamics when energy is transformed, the quantity of energy remains the same, but its ability to do work diminishes - Entropy is continuously increasing The Food Chain Layout - Tertiary Consumer - Secondary Consumer - Primary Consumer - Primary Producer Trophic Levels group species based on their primary source of nutrition and energy Autotrophs build molecules themselves using photosynthesis or chemosynthesis as an energy source Heterotrophs depend on the biosynthetic output of other organisms Primary Producers - support all other trophic levels - autotrophs - most are photosynthetic - include plants, algae, photosynthetic prokaryotes Primary Consumers - herbivores - anything that eats plants and primary producers Secondary Consumers - carnivores who eat herbivores Tertiary Consumers - carnivores that eat other carnivores Detritivores/Decomposers - heterotrophs that acquire energy from detritus, or nonliving organic material Primary Production Amount of light energy converted to chemical energy by autotrophs. Gross Primary Production (GPP) amount of energy from light converted to chemical energy of organic molecules, per unit time Net Primary Production (NPP) gross primary production minus the energy used by the primary producers for 'autotrophic respiration' (Ra) Net Ecosystem Production (NEP) measure of the total biomass accumulation during that time. Defined as GPP minus the total respiration of all organisms in the system (Rt) Nutrients main limitation in lakes and oceans Limiting Nutrients elements that hinders production when levels are low -N&P Light primary production decreases with increasing depth of water Eutrophication increase in primary producers due to nutrient availability from fertilizers decreases oxygen content Secondary production Amount of chemical energy in consumers' food that is converted to new biomass. Production efficiency (PE) % of energy stored in food that is used for growth and reproduction Net Secondary Production energy used for growth and reproduction Assimilation total energy consumed and used in growth, reproduction, and respiration Trophic-level transfer efficiency % of production transferred from on trophic level to the next (about 10%) Biomass Pyramid each tier represents the total dry mass of all organisms in one trophic level - show a sharp decrease at successively higher trophic levels Pyramid of Energy each tier represents the rate of energy production, rather than the biomass Why do these fish differ in color? Think of at least two possible explanations Different stages of their life cycle Genetic mutation Male and Female Camouflage Different ages Biology the science of life What are ways to understand the natural world using observation and reasoning Characteristics of Living Organisms are composed of cells are complex and ordered respond to their environment can grow and reproduce obtain and use energy maintain internal balance can change over time Levels of organization for living systems 1- Cellular 2- organismal 3- population Cellular Orgainization atoms-molecules-organelles-cells Cell is the basic unit of life Organismal Level tissues-organs-organ systems-organism Population Level population-species-community-ecosystem How do scientists study life? Reasoning What are the two types of reasoning scientists use deductive and inductive deductive reasoning general to specific All organisms are made of cells, humans are organisms and made of cells deductive reasoning inductive reasoning specific to general If robins, cardinals and sparrows have feathers, conclude all birds have feathers Inductive reasoning Scientific Method Model Approach -observation -hypothesis formation -Prediction -experimentation -conclusion Hypothesis a possible explanation for an observation What makes a hypothesis valid? Must be tested to determine its validity Is often tested in many different ways allows for prediction to be made Example Hypothesis Alternate Hypothesis: Individual sexes differ in color Predict: All female fish are one color and all male fish are one color, but differ from female fish Null Hypothesis- there is no difference or no effect- there are no color differences between males and females. Predict: Males and females are both white or blue Scientific theory is a body of interconnected concepts is supported by much experimental evidence and scientific reasoning is evaluated by peer review expresses ideas of which we are most certain A theory is not a _________ guess or lack of knowledge Science a way to understand the natural world Science must have: testable hypotheses repeatable observations and test Science can not test Explanations of the supernatural Science is limited to the natural world and natural processes Species individual that are able to reproduce multiple population of species community multiple species interacting together in a particular region prediction what you expect to see if your hypothesis is supported ecosystem A biological community of interacting organisms and their physical environment. population A group of individuals that belong to the same species and live in the same area abstract opening section of scientific paper that summarizes the research and conclusion applied science form of science that aims to solve real-world problems