Homework:
7th Graders: Tonight's homework: write a Reflection (Left side). Describe or research something in genetics that is interesting to you, then write at least 5 sentences about it.  Infectious Disease project deadline extended, now due Friday, Feb. 3.  Every project must include a poster or an essay.

6th Graders: copy into your vocab section in your science notebook the definitions for the words you don't have from these:

1. Controlled variable (aka control) - A variable in an investigation or experiment that is held constant.
2. Dependent variable - The observed phenomenon that is being measured; the result that you measure at the end.  Memory trick: "result"
3. Dissolve - To break down into smaller particles using a solvent. A solute (like sugar) dissolves into a solvent (like water) to form a solution.  
4. Independent variable - the variable that an experimenter chooses to change or manipulate, or play with. Memory trick: "choice"
5. Physical change - (yes, you have already seen this definition - rewrite it in your vocab section because its important) Change that does not alter the composition of a material. Ex: change of state; breaking up a piece of material into smaller pieces.
6. Saturated, saturation - A solution is "saturated" when the solvent has dissolved the maximum possible amount of a solute (in other words, the solution just can't take any more). Saturation means that the solution has become saturated.   

Soluble, insoluble - A substance (a solute) that is able to dissolve in a solvent (solid, liquid or a gas).



Solubility - how well a substance can dissolve in a certain solvent such as water; solubility can be measured, and varies from substance to substance.


Solute/solvent - the solute is a substance that dissolves in the solvent. Ex: sugar in water


Solution- The mixture that results when one substance, the solute, evenly dissolves in a solvent, another substance - usually a liquid such as water.


Variable - Any factor that can change the outcome of an experiment.
 
 A concept map is an example of a graphic organizer that shows relationships among important ideas. 

gas - substance that has no definite shape or volume; gas particles spread far apart.
liquid - substance with definite volume but no definite shape; particles in a liquid spread
far apart enough to flow or pour and take.

particles - the characteristic smaller pieces or parts, such as atoms or molecules, that
all substances are made of. Ex: Water = compound made of identical water molecules;
gold (an element) is made of identical gold atoms.

phase - a homogeneous state of matter - gas, liquid, or solid. During phase change, the
particles do not change, but their arrangement & distance from each other do.

physical change - difference in appearance that doesn't change the make up of the particles
Ex: tear or break material into smaller pieces; during a phase change from solid to liquid
(melting), liquid to gas (boiling, evaporating), solid to gas (sublimation), gas to liquid
(condensing), or liquid to solid (freezing).

physical properties - characteristic of a substance or material. Ex: color, density, flexibility,
hardness. These properties help identify pure substances and don't change if the sample is
large or very small.

quantitative data - measurements, such as volume or mass

qualitative - characteristics people can perceive without making measurements.

solid - substance with definite shape and volume, as particles are closely packed together, and move very little (vibration).

substance - Anything that has mass and takes up space.

vapor - The gas phase of a substance (ex: water vapor, not steam, is gaseous water).