Scientific Method
What are the five steps of the scientific method?
observation, hypothesis, experiment, data collection, conclusion
What is the name of the molecule/substance that contains the genetic code of living things?
DNA
What is the name of the negatively charged subatomic particle in atoms?
electron
Which type of macromolecule provides organisms with their main source of energy?
carbohydrates
What is the purpose of an enzyme?
to catalyze reactions (make them go faster)
A scientist wants to test how blue light exposure affects sleep. He exposes one group of participants to a long period of blue light before bedtime and exposes another group to a shorter period. He then measures how many hours each group sleeps. What are the independent and dependent variables in this experiment?
independent: length of blue light exposure
dependent: hours of sleep
What is the name of the process by which organisms break down materials for energy?
Metabolism
If a substance contains more H+ particles than OH- particles, will that substance be acidic or basic?
Acidic (pH less than 7)
What type of macromolecule is often found in membranes?
lipids
True or false: Any molecule can fit into any enzyme.
False: Enzyme-substrate pairings are very specific.
How does a scientific theory differ from a hypothesis?
Unlike a hypothesis, a theory is well-tested and explains multiple phenomena.
What is the name of the fundamental unit of life (the units that all organisms are made up of)?
Cell
What is the name of the bond that attracts two water molecules together (via the charges on their oxygen and hydrogen atoms)?
hydrogen bond
What do nucleic acids do?
Carry genetic code (make up DNA)
Name three factors that can stop an enzyme from working.
high temperature, extreme pH, regulatory molecules
What is the difference between a qualitative observation and a quantitative observation?
A quantitative observation includes numbers; a qualitative observation does not.
What is the name of the process by which organisms maintain a steady internal environment?
Homeostasis
Name one effect that is caused by the strong bonds between water molecules.
surface tension, cohesion, high melting and boiling points
What is the name of the smallers molecules that make up proteins?
Amino acids
What is the name of the energy it takes to start a reaction? What happens to this energy when an enzyme is involved?
activation energy; decreases
A team of doctors is testing a new drug for arthritis. To see whether the drug works, they give one group of participants the drug and another group of participants a placebo pill. They then measure how much each group’s arthritis symptoms improved. What was the control group in this experiment?
the group that received the placebo
What is the name of the process by which species change over time?
Evolution
Which subatomic particles are found in the nucleus of the atom?
protons and neutrons
What is something that proteins do in cells?
regulate reactions, transport materials, form structures, etc.
True or false: The substances found at the beginning of a chemical reaction are called products.
False: These are reactants.