Atomic Structure & Bonds
Water & pH
Carbohydrates & Lipids
Proteins & Nucleic Acids
Characteristics of Life
100
What is an ion? Give an example.
An atom that has gained or lost electrons, giving it a charge. Ex: Na⁺,Cl⁻, etc.
100
What causes water molecules to stick together?
The property of cohesion (due to hydrogen bonding)
100
What are the building blocks (monomers) of carbohydrates?
Monosaccharides (simple sugars like glucose).
100
What are the building blocks (monomers) of proteins?
Amino acids
100
What does it mean for something to be alive?
It must show all six characteristics of life.
200
What’s the difference between a chemical bond and an intermolecular force?
Chemical bonds (like covalent or ionic) hold atoms together within a molecule; intermolecular forces (like hydrogen bonds or Van der Waals) attract separate molecules to one another.
200
What property allows small insects to walk on water?
Surface tension, caused by cohesive hydrogen bonds.
200
What 3 elements are found in carbohydrates?
Carbon (C), hydrogen (H), and oxygen (O).
200
What are the four levels of protein structure?
Primary (chain of amino acids), secondary (folding like helices/sheets), tertiary (3D shape), quaternary (multiple chains)
200
Name two of the six characteristics of life.
Must list 2 of the following: Growth, reproduction, metabolism, response to stimuli, organization, homeostasis, adaptation.
300
What type of bond forms when atoms share electrons equally?
Nonpolar covalent bond.
300
What pH value is considered neutral and is also the pH of pure water?
pH 7
300
Compare and contrast carbohydrates and lipids.
Carbs: quick energy, polar, hydrophilic. Lipids: long-term energy, nonpolar, hydrophobic.
300
What are the two types of nucleic acids, and what do they do?
DNA (stores genetic info) and RNA (carries out instructions to make proteins)
300
What does “metabolism” mean?
All chemical reactions that occur within an organism to maintain life.
400
What type of bond forms between water molecules and why?
Hydrogen bonds, formed due to the attraction between the partial positive hydrogen of one molecule and the partial negative oxygen of another.
400
What is a buffer, and why is it important for living organisms?
A buffer is a weak acid or base that helps maintain a stable pH in organisms, aiding homeostasis.
400
What is the function of glycogen in animals?
It stores energy in muscles and the liver for later use.
400
Describe the structure of DNA
Double helix made of two strands held together by hydrogen bonds between complementary bases (A–T, C–G)
400
What does homeostasis mean, and give one example.
Maintaining internal stability; example could be body temperature regulation, blood pH balance, etc.
500
How many protons, neutrons, and electrons are in this element (assume this is the neutral Carbon-12 isotope)?
A standard, neutral carbon atom has 6 protons, 6 electrons, and 6 neutrons in the common Carbon-12 isotope.
To find the protons, neutrons, and electrons in an atom from the periodic table, first locate the element to find its atomic number (6), which equals the number of protons and, for a neutral atom, the number of electrons. Then, use the element's approximate atomic mass (e.g., 12 for carbon-12) and subtract the atomic number from it to find the number of neutrons (12 - 6 = 6 neutrons).
500
Why does ice float on water, and why is this important for life?
Ice is less dense due to hydrogen bonds forming a crystalline structure with more open space; this insulates aquatic life in winter.
500
What are two of the three types of lipids, and what are their functions?
List 2 of these:
triglycerides (energy storage)
phospholipids (cell membranes)
steroids (hormones and signaling)
500
How do proteins and nucleic acids work together to support life?
DNA provides instructions for building proteins, which perform nearly all cell functions.
500
How do living things adapt over time?
Through changes in genetic traits passed across generations that help survival in changing environments.