Learning Objectives Flashcards
Describe the components of an Atom
Electrons
Neurons
Proton
Differentiate between an element, a molecule and a compound
-Elements have only one kind of atom
-A molecule is a neutral particle that is held together by covalent bonds.
-A compound has more than one element chemically bonded
List the elements of life.
Carbon (C), hydrogen (h), oxygen (0), and nitrogen (N)
Define an isotope
Members of a family of an element that all have the same number of protons but different number of neutrons
Differentiate between covalent bonds and non-covalent bonds
chemical bonds formed when two atoms share electrons between themselves.
do not have a shared pair of electrons; instead, atoms attract opposite charges.
Differentiate between polar and non-polar covalent bonds
Polar- chemical bond where two atoms unequally share a pair of electrons
Non polar- chemical bond where two atoms share a pair of electrons with each other.
Describe:
-ionic
-hydrogen
-van-der Waals forces
-A bond formed by the electrostatic attraction of two oppositely charged ions
-A hydrogen atom is weakly shared between two electronegative atoms
-The weakest interaction due to the motion of electrons
What is matter?
Any substance that has mass
What is an element?
A substance whose atoms all have the same numbers of protons
What is a compound?
Has more than one elements chemically bonded
Discuss the four emergent properties of water
Cohesive behavior
- cohesion and adhesion
- surface tension
Ability to moderate temperature
- high specific heat
- stabilizing temperature
Expansion upon freezing
- floating of ice on liquid water
Versatility as a solvent
Explain what pH is in relation to H+ and OH- ions
pH measures the balance of H+ and OH- ions
More H+ ions = acidic (pH<7)
More OH- = basic (pH>7)
Equal H+ and OH- ions = neutral (pH = 7)
Explain acidic and basic properties in relation to pH
Acids have a pH below 7
High concentrations of H+ ions
Sour taste and corrosive
Eg. Hydrochloric acid
Basics have a pH above 7
High concentration of OH- ions ( more hydroxide ions than hydrogen ions )
Bitter taste and slippery feel
Eg. Sodium hydroxide
Explain why organisms are sensitive to changes in pH and temperatures
can directly affect the structure and function of biological molecules, especially protein and enzymes
Discuss the role of buffers in relations to pH
They allow biological fluids to maintain a relatively constant pH despite the addition of acids or bases
Referred to as H+ “ sponges” because they remove H+ from solution when levels increase and release when levels fall.
Define organic chemistry
The study of the structure properties, composition, reactions and preparation of carbon containing compounds
Define hydrocarbons
An organic compound consisting entirely of hydrogen and carbon
Define isomers
Organic compounds with the same molecular formula but different structures and properties
Types of isomers
Structural isomers
- different covalent arrangements of their atoms
Cis-trans isomers
- the same covalent bonds but differ in spatial arrangements around a double bond
Enantiomers
- are mirror images of each other
different types of functional groups on organic molecules
- Hydroxyl
- carboxyl
- carbonyl
- Amino
- sulfhydryl
- phosphate
- methyl
Discuss the functions of carbohydrates
Functions:
- fuel source - important source of energy when oxidized
- energy storage - starch in plants: glycogen in animals
- structural - cell walls in plants (cellulose) and bacteria ( peptidoglycan ); cell wall of fungi and in exoskeleton (chitin)
Discuss the basic structures of carbohydrates
Monosaccharides
- glucose
- fructose
- galactose
Disaccharides
- sucrose
- lactose
- maltose
Polysaccharides
- starch
- glycogen
- cellulose
Explain monosaccharides, disaccharides and polysaccharides
Monosaccharides - the simplest form of carbohydrates, consisting of single sugar units
Disaccharides - composed of two monosaccharide units linked by a glycosidic bond.
Polysaccharides - long chains of monosaccharide units. They often function as recognition signals on cell surfaces
Discuss the functions of lipids
Fuel source - important energy source when oxidized
Energy storage - plants store oil in seeds while humans and other mammals store fats and oils in adipose tissues
Structural - phospholipids, cholesterol and glycolipids in cell membranes
Cell communication - acts as ‘markers’ for cell recognition and communication
Hormones - many act as hormones ( steroid hormones )
