Cells & Life
What are the basic characteristics that an organism must have to be considered living?
Organization, metabolism/use of energy, growth and development, reproduction, response to stimuli, homeostasis, and adaptation/evolution.
What three subatomic particles make up an atom?
Protons, neutrons, and electrons.
What four major classes of organic molecules are found in living organisms?
Carbohydrates, lipids, proteins, and nucleic acids.
What pH range indicates an acid?
Below 7.
What is a hypothesis?
A proposed explanation or prediction that can be tested.
What is the difference between a prokaryotic cell and a eukaryotic cell?
Prokaryotic cells lack a nucleus and membrane-bound organelles. Eukaryotic cells have a nucleus and membrane-bound organelles.
What determines an element's atomic number?
The number of protons in the nucleus.
What is the monomer of a protein?
An amino acid.
What pH indicates a neutral solution?
7
What is the independent variable in an experiment?
The variable that the researcher deliberately changes or manipulates.
What is homeostasis?
The maintenance of a relatively stable internal environment despite changes in the external environment.
What is the difference between an ionic bond and a covalent bond?
An ionic bond involves the transfer of electrons, while a covalent bond involves the sharing of electrons.
What are the monomers of nucleic acids?
Nucleotides.
What is cohesion? What is adhesion?
Cohesion: The attraction between molecules of the same substance.
Adhesion: The attraction between molecules of different substances.
What is the dependent variable?
The variable that is measured or observed in response to the independent variable.
What are the levels of biological organization from smallest to largest?
Atom → molecule → organelle → cell → tissue → organ → organ system → organism → population → community → ecosystem → biosphere.
What type of bond is formed between water molecules and helps give water many of its important properties?
Hydrogen bonds.
What reaction joins monomers together by removing a molecule of water?
Dehydration synthesis.
What are buffers and why are they important in living organisms?
Buffers resist sudden changes in pH by accepting or donating hydrogen ions, helping maintain a stable pH.
What is the purpose of a control group?
It provides a baseline for comparison so researchers can determine the effect of the independent variable.
What are the levels of biological classification from most inclusive to least inclusive?
Domain → Kingdom → Phylum → Class → Order → Family → Genus → Species.
An atom has 6 protons, 6 neutrons, and 6 electrons. What are its atomic number and atomic mass?
Atomic number = 6. Atomic mass = 12.
What reaction breaks polymers apart by adding water?
Hydrolysis.
What are the properties of water?
Cohesion, adhesion, high specific heat, high heat of vaporization, polarity, and its ability to act as a solvent.
In an experiment testing whether fertilizer affects plant growth, one group receives fertilizer and another does not. Identify the independent variable, dependent variable, control group, and experimental group.