Mid-Year Review
Chemistry, Earth History, Infectious Diseases & Lithosphere
Chemistry-8.P.1- Understand the properties of matter and changes that occur when matter interacts in an open and closed container.
Chemical Properties- can only be observed during a chemical reaction, describes matter based on its ability to change into matter with different properties. (ex. flammability, reactivity)
Physical Change- does not form a new substance. (ex. painting a door, melting ice cream, buttering bread)
Chemical Change- one or more substances are changed into new substances that have new and different properties. (ex. a new color appears, heat light or sound is given off or absorbed, the change is difficult or impossible to reverse)
Elements- Building blocks of matter made of atoms. (ex. oxygen, gold, titanium)
Compounds- Substance formed when two or more elements chemically combine. (H2O)
Mixtures- Combination of 2 or more substances that is mixed but not combined. (ex. Heterogenous-can see parts of mixture, bowl of cereal, Homogenous- can't see parts of mixture, water, perfume)
Periodic Table- displays all of the known elements on earth. Each block on the periodic table represents one element. The table is organized by increasing atomic number. Vertical columns are called groups and are organized by the reactiveness of an element. Horizontal rows are called periods and are organized by the number of electron clouds surrounding the nucleus. Elements are grouped by metals, non-metals, and metalloids. Metalloids have both properties of metals and non-metals. Each element block tells you the atomic number, element name, element symbol, and the atomic mass of the element. The atomic number tells you the number of protons and electrons in the element. The element symbol is the first letter of element name or if that is taken, the first letter of it's Greek translation. The atomic mass is how many protons and neutrons in the nucleus. To find the the number of neutrons in the element, subtract the atomic number from the atomic mass.
Law of Conservation of Mass- states that matter cannot be created or destroyed, it can only be transferred from state to state.
Vocabulary- Matter: anything that has mass and takes up space. Solution: a substance made as a result of mixing a solid and a liquid and the solid dissolves. Atoms: the basic building block for all matter.
Earth History-8.E.2- Understand the history of Earth and it's life forms based on evidence of change recorded in fossil records and land forms
Index Fossils- fossils that compared to help identify specific periods of geologic time.
Ice Cores- an ice sample that gives weather patterns over time
Geologic Time Scale- used by geologists to describe the timing and relationships between events that have occurred throughout earth's history.
Relative Dating- used to determine the age of a fossil by looking at it's position in layers of sedimentary rocks.
Absolute Dating- used to determine the exact age of a rock or fossil.
Half-life- the time required for half of a substance that makes up a living organism to disintegrate (decay or break down)
Radioactive Decay- Carbon 14 wants to radioactive decay and change into Nitrogen Isotope, a whole different element.
Vocabulary- Geology: the study of the origin, history, and the structure of the earth. Fossil Record:a record of the total number of fossils that have been discovered. Fossil:naturally preserved remains or traces of animals or plants that lived in the geologic past. Uniformitarianism: the idea that laws and processes that happen on earth have always happened and continue to happen everywhere in the universe.
Infectious Diseases-8.L.1.-Understand the hazards caused by agents of diseases that effect living organisms.
Epidemic-A widespread outbreak of an infectious disease within a small population or community. (ex.Polio outbreak)
Pandemic-An outbreak of an infectious disease that affects large populations. (ex. Black Plague)
Prevention/Treatment- Vaccines help prevent viral infections. Antibiotics treat bacterial infections. Good Hygiene helps prevent any type of disease.
Biotechnology- the use of living cells, bacteria, etc., to make use full products (ex. fake tissues) One of the careers in the biotechnology field is a cell culture technician. Cell culture technicians grow living cells in culture flasks and maintain culture of embryonic stem cells. Biotechnology helps the agricultural field by genetically modifying crops so that insects don't eat them as much. Biotechnology helps the medical field by helping to come up with new vaccines to prevent the spread of viruses. Biotechnology helps the economy by creating more jobs.
Vocabulary- Genetic Engineering: the science of making changes to the genes of a plant or animal to produce a desired result. GMO: an organism or microorganism whose genetic material has been altered by the means of genetic engineering. Cloning: to produce a copy or imitation of. DNA:The molecule that contains the genetic code of organisms. Bio-Remediation: the use of microorganisms or other forms of life to consume and break down environmental pollutants in order to clean up a polluted site.