college bio quiz - chapter 2

1. How can radiation be used in medicine: Can be used for diagnosing and treating diseases. PET scans. In radiation they target cancer cells. Specific body parts may be lungs, breast, brain, or any area cancer cells may be present. 

2. Difference between atomic mass and atomic number: Atomic number tells how many protons are in an atom and atomic mass provides an average mass of the atom based on its isotopes. 

3. Difference between radioactive isotopes and regular isotopes: Regular isotopes are stable and don't undergo decay while radioactive isotopes are unstable and emit radiation as they decay into other elements or isotopes. 

4. What does proton number tell you about a substance: Tells you the number of protons in the nucleus of an atom. This number uniquely identifies an element. Also determines the chemical properties of the element.

5. Know that iron is a trace element: Trace elements are chemical elements required by living organisms in very small amounts, usually less than 0.01% of their body weight. 

6. What do buffers do: Substances that help maintain a stable pH in a solution by either absorbing excess hydrogen ions or donating hydrogen ions when necessary. 

7. What are the types of bonds that hold water molecules together: Hydrogen bonds

8. What holds one water molecule to another water molecule: Hydrogen bonds

9. Know that human body cells are roughly 70%-95% water

10. Be able to determine hydrogen, oxygen, or carbon number: Hydrogen=1, oxygen=8, carbon=6

11. Know the symbols of strong acids: Hydrochloric acid (HCI), Sulfuric acid (H2SO4), nitric acid (HNO3).

12. What is an isotope and what differs between isotopes and the regular:Isotope is a form of a chemical element in which the atoms have the same number of protons but a different number of neutrons in the nucleus. The difference is their atomic mass.

13. How do electrons move around the nucleus: In specific regions called electron shells/energy levels. 

14. What happens to water as it freezes: Molecules slow down and form a crystalline structure due to the hydrogen bonds stabilizing and becoming stronger. 

15. pH scale: what indicates an acid and what indicates a base: A value less than 7=acid and a value greater than 7=base.

16. How do water molecules interact with each other:Through hydrogen bonding. The positive hydrogen atoms of 1 water molecule are attracted to the negative oxygen atoms of the other water molecules. 

17. Be able to identify an ionic bond vs a covalent bond: Ionic bond is formed when 1 atom donates an electron to another atom which results in the creation of charged ions that attract each other. A covalent bond is formed when 2 atoms share 1 or more pairs of electrons allowing them to achieve a more stable electron configuration. 

18. Difference between solvent, solute, and solution: Solvent= the substance that dissolves a solute, solute= substance dissolved in the solvent, and solution =homogeneous mixture that results from the combination of the solvent and solute. 

19. What does atomic number represent: The number of protons in the nucleus of an atom. 

20. Identify what happens in a covalent bond: Two atoms share 1 or more pairs of electrons. This allows each atom to achieve a more stable electron configuration. 

21. What is located in the nucleus of an atom vs outside the nucleus: Inside the nucleus is the protons and neutrons, outside the nucleus is the electrons. 

22. Radiometric dating is using the decay of radioactive isotopes: 

23. What is evaporative cooling and what does it do for the body: Process of which the surface of a liquid cools as it evaporates. This is essential for regulating body temperature especially when sweating to prevent overheating. 

Know the difference between cohesion, adhesion, and polarity: Cohesion=attraction between molecules of the same substance, adhesion=attraction between different substances, and polarity= uneven distribution of electrical charge in a molecule.