Characteristics of Life
True or False: an individual organism can evolve
False. Evolution occurs in a species over time.
The prediction of an outcome of an experiment.
Hypothesis
An atom is composed of subatomic particles called:
Protons, neutrons, and electrons
The property of water that allows water molecules to stick to itself
Cohesion
What is the range of the pH scale?
0-14
True or False: A virus is considered a living thing
False
What is the relationship between the independent variable and the dependent variable?
The dependent variable is affected by the independent variable.
Atomic number is based on the number of _______
Protons
The property of water that allows water molecules to stick to other substances
Adhesion
What is the relationship between a solvent and solute?
Solvent dissolves the solute.
True or False: The characteristics of life are still debated among scientists
What is a controlled variable?
Something that remains constant during an experiment.
A variation of an element that has the same number of protons, but a different number of neutrons
Isotope
This phenomenon, due to cohesion and adhesion, allows water to travel up the inside of plants.
Capillary action
The pH of a substance is determined by the concentration of these two ions.
H+ and OH-
Give an example of an organism maintaining homeostasis.
Multiple responses possible
True or false: a good scientific hypothesis can be phrased as a question, rather than a statement
False. Hypothesis should be a statement.
1. A type of bond that involves transferring electrons.
2. A type of bond that involves sharing electrons.
2. Covalent
Hydrogen bonds form a "net" on the surface of water, allowing small objects to float on the top. This phenomenon is possible due to cohesion.
Surface tension
What is the difference between a solution and a suspension?
Solution-particles are distributed evenly, transparent/translucent, particles are invisible to the naked eye
Suspension-particles are not distributed evenly, cloudy or murky, particles are visible, there may be a precipitate at the bottom of the container.
List the 7 characteristics of life
Organization
Responds to stimulus
metabolism
evolves over time
reproduces
maintains homeostasis
grows and develops
A teacher studies the relationship between hours her students spend studying and their test scores. She has observed that students who study a lot get higher grades.
Students who spend at least 2 hours a week studying will receive a grade of 85% or higher on their test.
Describe the difference between a molecule and a compound
A molecule is two or more atoms bonded together.
A compound is two or more different atoms bonded together.
What does it mean to have a high specific heat capacity?
It takes a lot of energy to change the temperature.
Give an example of a strong acid, a strong base, and something with a neutral pH
Battery acid, stomach acid, lemon juice
Bleach, ammonia
Pure water