Characteristics of Life
Question: Every living organism consists of one or more of these basic units.
Answer: Cells
Question: What is the smallest unit of an element that still keeps the properties of that element?
Answer: Atom
Question: How many hydrogen atoms and oxygen atoms are in H₂O?
Answer: 2 hydrogen atoms and 1 oxygen atom
Question: Water has slightly positive and slightly negative ends. What is this property called?
Answer: Polarity
Question: Water formed a raised dome on a penny. What water property was directly observed?
Answer: Surface tension
Question: What is the process of keeping internal conditions stable, even when the environment changes?
Answer: Homeostasis
Question: Two or more atoms chemically bonded together form what?
Answer: Molecule
Question: How many total atoms are in CO₂?
Answer: 3 total atoms
Question: What is the attraction between water molecules called?
Answer: Cohesion
Question: Pepper rushed away from the dish soap because the soap disrupted what property at the water’s surface?
Answer: Surface tension
Question: A plant bends toward a sunny window. Which characteristic of life does this demonstrate?
Answer: Response to stimuli
Question: What is a substance made from atoms of two or more different elements chemically bonded together?
Answer: Compound
Question: How many different elements and total atoms are in NH₃?
Answer: 2 different elements and 4 total atoms
Question: What is the attraction between water and a different material, such as glass or paper-towel fibers, called?
Answer: Adhesion
Question: During the walking-water investigation, water traveled through a paper towel and entered another cup. What is this process called?
Answer: Capillary action
Question: A bacterium splits into two new bacteria. Which characteristic of life has occurred?
Answer: Reproduction
Question: Why is O₂ a molecule but not a compound?
Answer: It contains only one type of element.
Question: How many carbon, hydrogen, and oxygen atoms are in C₆H₁₂O₆? Also give the total number of atoms.
Answer: 6 carbon, 12 hydrogen, and 6 oxygen atoms; 24 total atoms
Question: Water resists rapid temperature changes because it has what property?
Answer: High specific heat
Question: What two attractions help water climb through the tiny spaces in a paper towel?
Answer: Cohesion and adhesion
Question: After running, your breathing and heart rate increase to deliver more oxygen. Name the two characteristics of life demonstrated.
Answer: Energy use or metabolism and homeostasis
Question: Classify CO₂ in every way that applies: atom, molecule, element, or compound.
Answer: Molecule and compound
Question: Count every atom in Al₂(SO₄)₃. Give each element count, the number of different elements, and the total number of atoms.
Answer: 2 aluminum, 3 sulfur, and 12 oxygen atoms; 3 different elements and 17 total atoms
Question: Ice floats because solid water has what relationship to liquid water?
Answer: Solid water is less dense than liquid water.
Question: Predict what detergent could do to an insect standing on pond water. Explain why.
Answer: The insect could sink because detergent lowers or disrupts the water’s surface tension.