Lesson 2.1 -
Nature of Matter
Nature of Matter
Name the three subatomic particles and their charges.
Protons - Positive
Neutrons - Neutral
Electrons - Negative
True or False: Acidic substances have a lower pH than alkaline substances.
True
True or False: Carbohydrates and proteins each provide approximately 4 food Calories per gram.
True
2H + O -> H2O
Identify the reactant and product.
Hydrogen and Oxygen are the reactants
H2O is the product
The atomic number of an element tells you the number of:
Protons
Which part of a water molecule has a slightly negative charge?
Oxygen
The monomer for carbohydrates is
monosaccharides
What attaches to the active point on an enzyme?
Substrate
Describe the importance of valence electrons. Where are they located?
Give an example of a solution. Identify the solute and the solvent.
Saltwater. The salt is the solute and the water is the solvent.
What are the two types of nucleic acids?
RNA and DNA
What is the main purpose of a biological catalyst.
To speed up a reaction by lowering activation energy.
Describe a covalent bond. How many covalent bonds exist.
A covalent bond is a chemical link formed when two atoms share one or more pairs of electrons to make them more stable. There are three covalent bonds: single (each atom shares 1 electron), double (each atom shares 2 electron) or triple (each atom shares 3 electron).
Give an example of cohesion and adhesion.
Cohesion: Water droplets beading on a leaf, making larger droplets.
Adhesion: Water sticking to the windshield during a storm.
Identify the four major types of carbon compounds and describe one important function of each.
Carbohydrates: Provides fast energy
Lipids: Stores energy
Proteins: Builds biological structures
Nucleic Acids: Transfers genetic information.
Explain how changes in temperature or pH can affect an enzyme's activity. What does it mean when an enzyme becomes denatured?
Enzymes that are not in their optimum conditions may move to slowly or begin to be misshaped (denatured).
Describe an ionic bond.
This happens when one atom completely transfers one or more valence electrons to another atom, typically occurring between a metal (which loses electrons to become a positive cation) and a nonmetal (which gains electrons to become a negative anion). The two atoms are attracted to each other because of the opposite charges that form between the two atoms.
Describe hydrogen bonding.
Hydrogen forms between water molecules. It is due to the slightly more negative oxygen portion of the molecule being attracted to the slightly more positive hydrogen portion. This creates a weak bond between the hydrogen molecules, creating a "blanket affect".
Name 4 things proteins can do in biological organisms.
- Build structures (muscles, bones and tissue)
- Speed up chemical reactions
-Move substances in and out of cells
- Protect cells from disease or illness
Describe the difference between a lock & key enzyme model and an induced-fir enzyme model.
The lock-and-key model views an enzyme's active site as a rigid, pre-formed structure that matches a specific substrate. In contrast, the induced-fit model describes the active site as flexible, morphing its shape to snugly grip the substrate upon binding.