Scientific Method • Collaborate • Share info • Build upon other work
Direct Relationship variable increases and other variable increases
Inverse Relationship variable increases and other variable decreases
Linear Relationship each unit change in the x variable will bring about the same change in the y variable
Importance of Nutrient Cycling • It prevents wastes, which would cause problems, from accumulating. • It assures that the ecosystem will not run out of essential elements.
Carbon Cycle 1. Begin with a CO2. 2Photosynthesis 3. Food chains 4. Cell respiration
All organisms are made of roughly the same organic molecules in similar proportions • A measure of their dry weight is a rough measure of the energy they contain.
Biomass • A census of the population, multiplied by the weight of an average individual in it • Gives an estimate of the weight of the population.
Trophic level Secondaryconsumers Human meat-eaters Cattle Primaryconsumers Human vegetarians Corn Corn Producers 0 • A production pyramid explains why meat is a luxury for humans • A field of corn • Can support many more human vegetarians than meat-eaters Figure 37.14
Biomagnification • The increase of the concentration of a substance that occurs in the food chain. • Substances - pesticides or heavy metals • The substances become concentrated in tissues or internal organs because the substances are very slowly metabolized or excreted.
Eutrophication • Occurs when a body of water acquires a high concentration of nutrients (phosphates and nitrates). • This increases amount of algae in water. • As the algae die/decompose, high levels of organic matter and the decomposing organisms deplete the oxygen from the water. • This causes the death of other organisms (fish).
Greenhouse Gases • Carbon Dioxide – fossil fuels, solid waste, trees • Methane – production and transportation of coal, natural gas, and oil • Nitrous Oxide – agricultural and industrial • Fluorinated gases – industrial, commercial, and household uses
Fossil Fuels • Fuels formed from remains of plants and animals • Ex: Natural gas, oil coal
Ozone Layer • Ozone - 0₃ - naturally occurring in the stratosphere • Ozone layer - Protects earth from ultra violet rays • CFC’s –– destroy ozone by releasing chlorine into the atmosphere
Atmospheric CO2 is reflecting heat back down to the planet’s surface. • Only by phasing out coal use, ending deforestation and reducing the use of other fossil fuels can the numbers be reversed.
Other Causes • Clear cutting of forests • Increased use of fossil fuels • Methane pollution
Greenhouse Effect • Car in summer • Greenhouse gases absorb some the energy radiated from the earth and trap it in the atmosphere. • Human activities have INCREASED the amount of greenhouse gases
Robert Hooke • Coined the name cell • Looked at cork cells under microscope
Photosynthesis • Carbon Dioxide + Water Glucose + Oxygen
Photosynthesis • Green plants and algae use the solar energy and molecules of CO2 into sugar/starch and 02. • CO2 + H20 C6H12O6 + O2
Primary Productivity • is the production of organic compounds from atmospheric or aquatic CO2 through the process of photosynthesis
Meiosis • Occurs in plants and animals that reproduce sexually. • Usually occurs in specialized sex organs - Ovaries, Testes
Prophase I • Chromosomes form • Homologous pairs come together • Crossing Over occurs
Frederick Griffith - studying 2 strains of bacteria • 1 causes pneumonia, 1 harmless • When killed pathogenic bacteria and mixed with living healthy bacteria - some converted • Martha Chase and Alfred Hershey - showed that DNA was genetic material • Used radio isotopes to label DNA and protein in Phage T2 and ecoli cells • Sulfer - protein • Phosphate - DNA
Genetic Engineering • The direct manipulation of genes for practical purposes
Cloning • Nuclear Transplantation: replaces the nucleus of an egg cell or a zygote with a nucleus of an adult somatic cell • Cells divides creates blastocyst • Reproductive Cloning: If animal is a mammal, the blastocyst is implanted into uterus for further development • Therapeutic Cloning: Produce embryonic stem cells for therapeutic treatments
Recombinant DNA Technology • Combining genes from different sources into a single DNA molecule • Can use different species • Often uses plasmids
Recombinant DNA • DNA from two different sources are combined into the same DNA
PCR • Polymerase Chain Reaction • DNA is copied many times in a test tube. • Process can generate 100 billion copies of DNA in 4 hours