Untitled Flashcards Set

Atomic Structure and Properties

1. Atomic Number
   The number of protons in an atom’s nucleus; determines the element.

2. Atomic Weight (Atomic Mass)
   The total mass of an atom, calculated as the sum of protons and neutrons.

3. Valence Shell
   The outermost shell of electrons in an atom, which determines how an atom bonds with others.

4. Inert Gases (Noble Gases)
   Elements in group 18 of the periodic table, such as helium, neon, and argon, which are chemically stable and rarely react.

5. Ion
   An atom or molecule that has gained or lost one or more electrons, resulting in a positive or negative charge.

6. Isomers
   Molecules that have the same chemical formula but different structures.

7. Isotopes
   Atoms of the same element with different numbers of neutrons, resulting in different atomic masses.

Chemistry in Biology

8. Solute
   A substance that is dissolved in a solution (e.g., salt in water).

9. Solvent
   A substance that dissolves a solute (e.g., water).

10. Tonicity
    The ability of a solution to affect the shape of a cell by altering its water content (hypertonic, hypotonic, isotonic).

Biology and Cell Structure

11. Hypothesis
    A testable prediction or explanation for a phenomenon.

12. Biology
    The scientific study of life and living organisms.

13. Eukaryote
    Organisms whose cells have a nucleus and other membrane-bound organelles (e.g., plants, animals, fungi).

14. Prokaryote
    Single-cell organisms without a nucleus or membrane-bound organelles (e.g., bacteria).

15. Nucleus (of a cell)
    The membrane-bound organelle that contains the cell’s genetic material (DNA).

16. Nucleus (of an atom)
    The dense, positively charged center of an atom, consisting of protons and neutrons.

17. Mitochondrion
    Organelles that generate energy for the cell in the form of ATP (powerhouse of the cell).

18. Plasma Membrane
    The flexible boundary around a cell that controls the movement of substances in and out.

19. Cell Wall
    A rigid structure outside the plasma membrane in plant cells, fungi, and some bacteria, providing shape and support.

20. Golgi Complex/Apparatus
    An organelle that modifies, sorts, and packages proteins and lipids for transport.

21. Ribosome
    Small organelles that synthesize proteins by translating messenger RNA (mRNA).

22. Endoplasmic Reticulum (ER)
    A network of membranes involved in protein and lipid synthesis.

• Rough ER has ribosomes; smooth ER does not.

23. Lysosome
    Organelles that contain digestive enzymes to break down waste and cellular debris.

24. Chloroplast
    Organelles found in plant cells that capture light energy to produce food through photosynthesis.

Biochemistry

25. Enzyme
    A protein that acts as a catalyst to speed up chemical reactions.

26. Substrate
    The substance on which an enzyme acts.

27. Active Site
    The region on an enzyme where the substrate binds.

28. Energy of Activation
    The energy required to start a chemical reaction.

29. Kinetic Energy
    The energy of motion.

30. Potential Energy
    Stored energy, often based on an object’s position.

31. ATP (Adenosine Triphosphate)
    The primary energy carrier in cells.

Transport and Energy in Cells

32. Osmosis
    The diffusion of water across a semi-permeable membrane.

33. Diffusion
    The movement of particles from an area of high concentration to low concentration.

34. Facilitated Diffusion
    The movement of molecules across a membrane via transport proteins, down the concentration gradient (no energy required).

35. Active Transport
    The movement of molecules across a membrane against the concentration gradient, requiring energy.

36. Passive Transport
    The movement of molecules across a membrane without energy, down the concentration gradient.

37. Concentration Gradient
    The difference in the concentration of molecules in two regions.

Macromolecules and Chemical Reactions

38. Dehydration Synthesis
    A chemical reaction in which two molecules are joined by removing a water molecule.

39. Hydrolysis
    A chemical reaction in which a water molecule is added to break bonds between molecules.

40. Monomer
    A small molecule that can combine with others to form a polymer.

41. Polymer
    A large molecule made up of repeating units (monomers).

42. Saturated
    A type of fat molecule with no double bonds between carbon atoms, solid at room temperature.

43. Endergonic
    A reaction that requires energy input to proceed.

44. Exergonic
    A reaction that releases energy.

45. Conservation of Energy
    The principle that energy cannot be created or destroyed, only transformed.

46. Selective Permeability
    The property of a membrane that allows some substances to pass while blocking others.

Additional Review Questions

1. An atom has:

   • Atomic number = 6, Atomic mass = 13.

   • What atom is this? Carbon

   • How many Protons? 6

   • Electrons? 6

   • Valence Electrons? 4

   • Neutrons? 7

2. Name the domains:

   • Bacteria, Archaea, Eukarya

3. Hierarchy from atom to biosphere:

   • Atom → Molecule → Cell → Tissue → Organ → Organ System → Organism → Population → Community → Ecosystem → Biosphere

4. Types of Bonds:

   • Covalent Bond: Between H and O within a water molecule

   • Hydrogen Bond: Between H of one water molecule and the O of another

   • Ionic Bond: Between a positive ion and a negative ion

   • Peptide Bond: Between the carboxyl group of one amino acid and the amino group of another

5. Elements found in all organic molecules:

   • Carbon, Hydrogen, Oxygen, Nitrogen

6. Which organic molecules have the formula C₆H₁₂O₆?

   • Carbohydrates (Glucose)

7. What happens to a red blood cell in different solutions?

   • Hypertonic solution: Shrinks

   • Hypotonic solution: Swells and may burst

   • Isotonic solution: No change

8. Describe the structure of the plasma membrane:

   • The plasma membrane is a phospholipid bilayer with embedded proteins, cholesterol, and carbohydrate chains, controlling the movement of substances in and out of the cell.

Prefixes and Suffixes

• More: -er, -more

• Less: -less

• Same: Iso-

• Many: Poly-

• Sugar: -ose

• Enzyme: -ase

• Water: Hydro-

• Break down: -lysis

• Cell: -cyte

Periodic Table

• Columns: Indicate elements with similar properties (groups).

• Rows: Indicate the number of electron shells around the nucleus.