AFOQT AFOQT General Science Biology and Chemistry 2 — Questions and Answers
Question 1: DNA is stored primarily in which part of the eukaryotic cell?
- Cytoplasm
- Mitochondria
- Cell membrane
- Nucleus (Correct answer)
Correct answer: Nucleus
The nucleus houses the cell's genetic material as chromosomes and serves as the cell's control center.
Question 2: An exothermic chemical reaction is one that:
- Absorbs heat from surroundings
- Releases heat to surroundings (Correct answer)
- Requires a light catalyst
- Produces only water as a product
Correct answer: Releases heat to surroundings
Exothermic reactions release energy as heat to the surrounding environment, causing the surroundings to warm.
Question 3: Osmosis is best defined as the movement of:
- Solutes from high to low concentration
- Water across a semipermeable membrane toward higher solute concentration (Correct answer)
- Oxygen across cell membranes
- Proteins through active transport channels
Correct answer: Water across a semipermeable membrane toward higher solute concentration
Osmosis is the passive diffusion of water through a semipermeable membrane from an area of lower to higher solute concentration.
Question 4: The atomic number of an element represents:
- The number of neutrons in the nucleus
- The atomic mass of one atom
- The number of protons in the nucleus (Correct answer)
- The number of valence electrons
Correct answer: The number of protons in the nucleus
The atomic number equals the number of protons in an atom's nucleus and uniquely identifies each element.
Question 5: Which type of organism breaks down dead organic matter and recycles nutrients back into the ecosystem?
- Producers
- Primary consumers
- Decomposers (Correct answer)
- Apex predators
Correct answer: Decomposers
Decomposers such as fungi and bacteria break down dead organic material, returning essential nutrients to the soil.
Question 6: In ionic bonding, a chemical bond forms when:
- Two atoms share electrons equally
- One atom transfers electrons to another atom (Correct answer)
- Atoms share electrons unequally
- Two nonmetals repel each other
Correct answer: One atom transfers electrons to another atom
Ionic bonds result from the complete transfer of electrons from a metal to a nonmetal, forming oppositely charged ions.
AFOQT AFOQT General Science Biology and Chemistry 2
DNA is stored primarily in which part of the eukaryotic cell?