Ch. 2 Chemical Composition of the Body Flashcards
Molecules bond because they don’t like to be ____.
Unpaired
Unpaired electrons are called ____ ____.
Free radicals
Covalent Bonds
Share a pair of electrons; require energy to break
Single, double, and triple bonds (triple covalent is about as molecularly strong as we’re going to get)
Polar (positive and negative end) versus non polar (no region of charge) molecules
Polar bond vs Nonpolar bond
Polar: charges aren’t evenly distributed, causing + and - ends
Nonpolar: not water soluble, no charge
Ionic bonds
Atoms gain or lose electrons from neighboring atoms
Opposite charges attract
Hydrogen bonds
Weak and partial
Water surface tension
Important in DNA structure
Van der Waals forces
Weak and nonspecific
Hydrogen bonding between adjacent molecules creates ____ ____.
Surface tension
Aqueous
Water-based
Solution
Solute dissolved in solvent ex: sweet tea.
Solute (sugar) dissolved in solvent (tea)
Solubility
Ease of dissolving
Hydrophilic
Dissolves in water, highly soluble
Hydrophobic
Does NOT dissolve in water (ex: oil and water), low solubility
pH
Measure of the concentration of free H+
Acid
Contributes to H+ solution
Buffer
moderates changes in pH in blood plasma, pH is stabilized by bicarbonate (HCO3-)
How do lungs and kidneys help to maintain pH?
Lungs maintain CO2 levels
Kidneys maintain bicarbonate levels
Humans function on the slightly ___ side of the pH scale.
Basic (7.35-7.45)
pH: What’s the Acidic range?
1-6
pH: What number on the pH scale is Neutral?
7
pH: What’s the Basic range?
8-14
Carbohydrates (CHO)
Most abundant biomolecule; carbon + water
Monosaccharides (glucose)
Disaccharides (2 glucose)
Polysaccharides (many glucose)
Why are CHOs important?
Cellular recognition and fuel source
What is this structure?
a CHO
What is this structure?
a Polysaccharide
Lipids
Carbon and hydrogen (NO water)
Backbone of glycerol and 1-3 fatty acids
Nonpolar
Fats (animal, solid at room temperature)
Oil (plant, liquid at room temperature)
Saturation refers to double bonds
Is this a saturated or unsaturated fatty acid?
Saturated
Is this a saturated or unsaturated fatty acid?
Unsaturated (has double bonds where hydrogen has been lost)
What is the backbone in a triglyceride?
Glycerol
Lipid-Related Molecules: Eicosanoids
Important for regulating cell function
Lipid-Related Molecules: Steroids
Cholesterol is the primary source of steroids in the human body
Need cholesterol for hormone signaling
Lipid-Related Molecules: Phospholipids are important in ____ ____.
Cellular Structure
What is this structure?
Phospholipid
What is this structure?
A protein
Discuss proteins
Made up of amino acid (AA) building blocks
Enzymes
Membrane transporters
Signal molecules
Receptors
Binding proteins
Immunoglobulins
Regulatory proteins
What is this structure?
Peptide bond
What type of protein structure is this?
Primary
What type of protein structure is this?
Secondary structure (alpha helix)
What type of protein structure is this?
Secondary (beta-pleated sheet)
What type of protein structure is this?
Tertiary
What type of protein structure is this?
Quaternary
Secondary vs Tertiary vs Quaternary protein structures
Secondary: interactions happening in proximal parts of chain, starts to take shape
Tertiary: starting to fold back on itself to make intricate shapes
Quaternary: 2 different peptide chains came together to make a structure
Issues with protein structure can lead to ____.
Disease (ex: resulting from protein folding incorrectly)
Complex structure = complex function
What determines the shape/structure of proteins?
Hydrogen bonds are critical in determining structure/shape of proteins
Nucleic Acids
Important for DNA (chain of nucleic acids)
Important for ATP (cellular energy)
What do these bases make up?
DNA
DNA vs RNA
DNA contains:
deoxyribose
thymine
RNA contains:
ribose
uracil
