Chapter 3: The Composition of Living Things: Understanding Basic Chemistry Flashcards
__________ bonds involve unequal sharing of electrons.
Polar Covalent
What pH number represents a basic solution?
14
Benedict’s solution tests for…
Monosaccharide/Glucose
If you see a blue color after using Benedict’s solution, does this indicate a positive or negative result?
Negative
Describe the organization of the pH scale.
1 = acidic 7 = neutral 14 = basic
Compare and contrast an acid and a base, and provide examples of each.
An acid contains H+ ions and lower pH
ex: stomach acid
A base haas H- ions and a higher pH
ex: soap
Atomic number
The number of protons in the nucleus.
Atomic Mass
The number of protons plus the number of protons plus the number of neutrons in the nucleus.
Molecule
Results from the chemical union of two or more atoms.
Isotopes
Atoms that have the same number of protons and a varied number of neutrons.
Compounds
Molecules composed of different elements.
Ionic Bond
The attraction of oppositely charged ions.
Covalent Bonds
Result from sharing electrons.
Nonpolar Covalent Bonds
Equal sharing of electrons.
Polar Covalent Bonds
Unequal sharing of electrons.
Hydrogen bonds
Weak bonds
Solution
A liquid composed of a uniform mixture of two or more substances.
Solvent
The dissolving medium.
Solute
The dissolved substance.
Carbohydrates
Organic compounds that contain carbon, hydrogen, and oxygen in a 1:2:1 ratio.
Lipids
Diverse organic compounds that include fats, waxes, phospholipids, and steroids.
Proteins
The most numerous and complex molecules in living organisms.
Monosaccharides
The simplest forms of carbohydrates are known as single sugars, simple sugars, or monosaccharides.
Dehydration Synthesis
Two monosaccharides combine in a process known as dehydration synthesis or condensation, to form a double sugar or disaccharide.
Disaccharide
A double sugar.
Hydrolysis
Disaccharides can be broken down into their simpler sugars through a process called hydrolysis.
Polysaccharides
Complex carbohydrates built from simple carbohydrates and linked through dehydration synthesis.
Starch
A storage polysaccharide that consists of glucose molecules in plants.
Glycogen
Or animal starch, is a highly branched, glucose-rich polysaccharide stored in the liver and skeletal muscle of animals.
Chitin
A modified polysaccharide, is the main component in the cell walls of some fungi and the exoskeleton of insects and other arthropods.
Saturated Fatty Acids
All of the carbon atoms are linked by single bonds and consist of the maximum number of hydrogen atoms.
Saturated Fats
Consist of saturated fatty acids with the maximum number of hydrogen atoms.
Unsaturated Fatty Acids
Do not have the maximum number of hydrogen atoms. They have one or more double bonds between the carbon atoms.
Monounsaturated
An unsaturated fatty acid with one double bond.
Polyunsaturated
A fatty acid with more than one double bond.
Waxes
Consist of an alcohol bonded with a long-chain fatty acid.
Amino Acids
Proteins are composed of building blocks known as amino acids.
Peptide Bonds
A covalent bond that forms between the amino group of one amino acid and the carboxyl group of another amino acid during a dehydration synthesis reaction.
Polypeptides
Formed by additional amino acids joined to the chain.
Biuret Test
Commonly used to detect the presence of a protein. (blue-green = no protein, violet = protein)
Sudan Test
Used to detect lipids. (No change = no lipid, orange = lipid present)
Iodine Test
Used to detect starch. ( blue-black = starch present, yellow-brown = no starch)
Benedict’s Test
Used to detect reducing sugar. ( blue = no reducing sugar, green/yellow/orange/red = reducing sugar present)
