Unit 2: Chemical Level of Organization Flashcards
(26 cards)
What is an atom?
A particle that makes up all matter, including all parts of the human body.
What are the 3 types of subatomic particles?
Nucleus of atom contains:
i. protons (p+/positive charge)
ii. neutrons (n0/neutral charge)
Orbiting nucleus are:
iii. electrons (e-/negative charge)
What charge are atoms?
Atoms are electrically neutral - the # of electrons and protons are equal. Neutrons MAY NOT be equal to these (these diff. forms = isotopes).
What is an ion?
If an atom loses or gains an electron, it is NO LONGER NEUTRAL and becomes an ion.
What is an ion that gains electrons called?
A negative ion, or anion.
What is an ion that loses electrons called?
A positive ion, or cation.
What are some of the important ions? (Aka electrolytes).
Calcium (Ca2+), sodium (Na+), potassium (K+), hydrogen (H+), chloride (Cl-)
- What is a chemical bond?
- What do chemical bonds allow for?
- It bonds (or holds) atoms together to form molecules.
- They allow for the formation of chemical compounds which may be organic or inorganic.
What is the first type of chemical bond?
1) An ionic bond = atom to atom transfer of electrons.
- ex. = table salt (not all salts = table salt) - made of anions and cations (ex. = NaCl, KCl)
- So Na loses 1 electron and becomes Na+, and Cl gains 1 electron and becomes Cl-, then the positive (Na+) and negative (Cl-) ions attract and form the bond.
- @ in H2O, NaCl dissociates (dissolves/separates/ionizes) into ions: Na+, Cl-
What is the second type of chemical bond?
2) Covalent bonds = share electrons between atoms (ex. = O2 [oxygen])
What are organic substances?
Covalently bonded carbon (C) atoms (ex.s = carbs, proteins, lipids, nucleic acids)
What are inorganic substances?
They usually lack C atoms.
- ex.s = water (H2O), salts (consist of anions and cations - ex. = NaCl), gases (O2)
- EXCEPTIONS = H2CO3 (Carbonic Acid), HCO3 (Bicarbonate), CO2 (Carbon Dioxide), and CO (Carbon Monoxide)
- What is water?
- Layout, molecular organization, reactions to it, roles
- An inorganic substance that is most abundant substance in cells (! so body does contain inorganic substances)
- Layout = 2 H atoms and 1 O atom
- Polar molecules = unequal sharing of electrons leads to slight charge difference
- Many reactions in body take place in H2O b/c it is a universal solvent (and we = like an ocean/our bodies are like bags of water)
- Transports chem.s (like O2 and nutrients), and maintains body temp (~37 degrees Celsius)
What are acids and bases?
They are electrolytes (like salts), and are important in maintaining pH balance of cells, organs, and blood (w/in narrow ranges)
- They can be organic OR inorganic
What do acids do?
They dissociate in H2O, releasing H+ ions (so increases H+ ion concentration)
- ex. = hydrochloric acid (HCI) in H2O = increase in H+ AND Cl-
High H+ = low/acidic pH
What do bases do?
They bind (or buffer)/ remove free H+ ions in H2O
- ex. 1 = NaOH (base) in H2O becomes Na+ AND OH- (hydroxyl ion)
- ex. 2 = HCO3- (bicarbonate) and H+ become H2CO3 (carbonic acid) THEN H2O and CO2
Low H+ = high pH
OH- and HCO3 act as bases by binding to the free H+ ions
What is the pH scale?
- A measure of the [H+] of free H+ in solution
- OH- and H+ become H2O (neutralization)
- As move from basic to acidic, = higher [H+] (AND V.S.)
- 0 (acidic) —to— 7 (neutral) —to— 14 (basic/alkaline)
- ex. = pH of blood = 7.35-7.45
What is the first important organic substance? (we are what we eat)
1) Carbohydrates
- Consist of C, H, and O (formula = (CH2O)n [n = #]
- Functions:
a) source of energy for cells (ex. = C6H12O6 - glucose)
b) cellular structures (ex.s = DNA & RNA)
- Naming:
a) monosaccharides (simple sugars) = basic building blocks of other carbs (ex.s = glucose, fructose, ribose, deoxyribose)
b) disaccharides = 2 mono.s covalently bonded together (ex.s = glucose and fructose = sucrose)
c) polysaccharides = many mono.s (basic building blocks) bonded together (ex.s = glycogen [animals] and starch [plants])
What is the second important organic substance?
2) Lipids
- C, H, O (ratio diff. from carbs)
- Ex.s = fats, oils, waxes, fatty acids (FA - so are lipids AND acids)
- Insoluble (nonpolar) in water (“oil and water don’t mix”)
- Functions:
a) protect organs (padding - like w/ abs, b/c don’t have bones around them)
b) build cell membranes
c) source of stored energy
What is type a) of lipids?
a) Glycerides
- Most common lipid in body and diet
- Composed of 2 building blocks:
i. glycerol (backbone) & ii. fatty acids
- Naming for glycerides depends on # of FAs:
i. glycerol + 1 FA = monoglyceride
ii. glycerol + 2 FAs = diglyceride
iii. glycerol + 3 FAs = triglyceride
What is type b) of lipids?
b) Phospholipids
- 3 building blocks:
i. Phosphate “head” group (polar) (also hydrophilic = water
soluble)
ii. Glycerol backbone and iii. 2 FAs “tails” (non-polar)
- both = hydrophobic (water insoluble)
What are types c) and d) of lipids?
c) Cholesterol
- Found in cell membranes and used to synthesize steroids
d) Steroids
- Derived from cholesterol
- ex.s = bile salts, vitamin D, some hormones (like testosterone and estrogen)
What is the third important organic substance?
3) Proteins
- Consists of C, H, O, N (and sometimes S) (ex. = albumin = most abundant blood plasma protein)
- Functions:
a) structural materials (like collagen)
b) enzymes (which speed up chem. reactions), hormones, transporters (which move things across cells)
c) antibodies
d) source of energy (esp. if carbs + lipids in low supply)
- Naming:
a) Amino acids = basic building blocks of all proteins (and use the name of the aa itself - like glycine)
b) Dipeptides = 2 amino acids
c) Polypeptited = many aa
d) Protein = 1 or more polypeptides folded into its final shape
What is the fourth important organic substance?
4) Nucleic Acids
- Consists of C, H, O, N, P
- 2 forms:
a) DNA (deoxyribonucleic acid)
b) RNA (ribonucleic acid)
- Building blocks called nucleotides
- Each nucleotide contains:
a) PO4- (phosphate)
b) Monosaccharide (simple sugar) (deoxyribose in DNA and ribose in RNA)
c) Organic bases:
i. Adenine (A)
ii. Thymine (T) - DNA ONLY
iii. Uracil (U) - RNA ONLY
iv. Cytosine (C)
v. Guanine (G)
