ch. 2 chem of life

Question 1

chemical elements

element

Answer 1

simplest form of matter to have unique chemical properties

Question 2

chemical elements

atomic number

Answer 2

number of protons in its nucleus

Question 3

chemical elements

periodic table

Answer 3

elements arranged by atomic number

24 elements have biological rule

6 elements=98.5% of body weight (oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus)

Question 4

chemical elements

minerals

Answer 4

inorganic elements extracted from soil by plants and passed up food chain to humans

Ca, P, Cl, Mg, K, Na, S

about 4% body weight

important for enzymes

electolytes: mineral salts needed for nerve and muscle function

Question 5

atomic structure

nucleus

Answer 5

center of atom

Question 6

atomic structure

proton

Answer 6

single + charge

Question 7

atomic structure

neutron

Answer 7

no charge

Question 8

atomic structure

atomic mass

Answer 8

equal to total number of protons and neutrons

Question 9

atomic structure

electron

Answer 9

in concentric clouds surrounding nucleus

single - charge

Question 10

atomic structure

an atom is electronically neutral as number of electrons equals number of

Answer 10

protons

Question 11

atomic structure

valence electrons orbit in the

Answer 11

outermost shell and determine chemical bonding properties of an atom

Question 12

isotopes and radioactivity

isotopes

Answer 12

varities of an element that differ only in the number of neutrons

extra neutrons increase atomic weight

Question 13

isotopes and radioactivity

istoper of an element are chemically similar because they

Answer 13

have the same number of valence electrons

Question 14

ions, electrolytes, free radicals

ion

Answer 14

charged particle with UNEQUAL number of protons and electron

Question 15

ions, electrolytes, free radicals

ionization

Answer 15

transfer of electrons from one atom to another

Question 16

ions, electrolytes, free radicals

anion

Answer 16

particle that GAINS electron

net negative

Question 17

ions, electrolytes, free radicals

cation

Answer 17

particle that LOSES electron

net positive charge

Question 18

ions, electrolytes, free radicals

ions with opposite charges are

Answer 18

attracted to each other

Question 19

ions, electrolytes, free radicals

electrolytes

Answer 19

substances that ionize in water and form solutions capable of conducting electric current

Question 20

ions, electrolytes, free radicals

Electrolyte importance

Answer 20

-Chemical reactivity, osmotic effects, electrical excitability
of nerve and muscle
– Electrolyte balance is one of the most important
considerations in patient care (imbalances can lead to
coma or cardiac arrest)

Question 21

ions, electrolytes, free radicals

Free radicals

Answer 21

• short-lived particles with an unusual
  number of electrons
  – Produced by normal metabolic reactions, radiation, certain
  chemicals
  – Trigger reactions that destroy molecules, and can cause
  cancer, death of heart tissue, and aging

Question 22

Ions, Electrolytes, and Free Radicals

Antioxidants

Answer 22

– Chemicals that neutralize free radicals
– Superoxide dismutase (SOD) is an antioxidant enzyme in
the body
– Selenium, vitamin E, vitamin C, and carotenoids are
antioxidants obtained through the diet

Question 23

Molecules and Chemical Bonds

Molecule

Answer 23

chemical particle composed of two or more atoms
united by a chemical bond

Question 24

Molecules and Chemical Bonds

Compound

Answer 24

molecule composed of two or more different
elements

Question 25

# Molecules and Chemical Bonds Molecular formula

Answer 25

identifies constituent elements and how many atoms of each are present

Question 26

# Molecules and Chemical Bonds Structural formula

Answer 26

identifies location of each atom

Question 27

# Molecules and Chemical Bonds Isomers

Answer 27

- molecules with identical molecular formulae but different arrangement of their atoms

Question 28

# Molecules and Chemical Bonds molecular weight (MW

Answer 28

of a compound is the sum of the atomic weights of its atoms

Question 29

# Molecules and Chemical Bonds Chemical bonds

Answer 29

hold atoms together within a molecule or attract one molecule to another Most important types of chemical bonds: ionic bonds, covalent bonds, hydrogen bonds, van der Walls forces

Question 30

# Molecules and Chemical Bonds Ionic bonds

Answer 30

* Attractions between anions and cations (example, NaCl) * Electrons donated from one atom to another * Easily broken by water

Question 31

# Molecules and Chemical Bonds Nonpolar bond

Answer 31

electrons shared equally (strongest bond

Question 32

# Molecules and Chemical Bonds Polar bond:

Answer 32

electrons shared unequally (spend more time near oxygen)

Question 33

# Molecules and Chemical Bonds Hydrogen bond

Answer 33

a weak attraction between a slightly positive hydrogen atom in one molecule and a slightly negative oxygen or nitrogen atom in another – Water molecules are attracted to each other by hydrogen bonds – Large molecules (DNA and proteins) shaped by hydrogen bonds within them – Important to physiology

Question 34

# Molecules and Chemical Bonds Van der Waals forces

Answer 34

weak, brief attractions between neutral atoms – Fluctuation in electron density within an atom creates polarity for a moment, and attracts adjacent atom for a very short time – Only 1% as strong as a covalent bond, but important in physiology (example, protein folding)

Question 35

# Acids, Bases, and pH acid

Answer 35

proton donor releases ions in water

Question 36

# acids bases and pH base

Answer 36

proton donor accepts ions

Question 37

# acids bases pH pH

Answer 37

measure derived from the molarity of ph 7.0 neutral pH less than 7 is acidic more than 7 is basic

Question 38

# acids bases pH pH is a measurement of molarity on a

Answer 38

logarithmic scale a change of one number on the pH scale represents a 10-fold change in concentration ph 4.0 is 10x more acidic than ph 5.0

Question 39

# acids bases pH buffers

Answer 39

chemical solutions that resist changes in pH maintaining normal ph of blood is crucial for physiological functions

Question 40

# metabolism oxidation reduction metabolism

Answer 40

all chemical reactions of the body

Question 41

# metabolism oxidation reduction catabolism

Answer 41

energy-releasing decomposition reactions breaks covalent bonds produces smaller molecules

Question 42

# metabolism oxidation reduction anabolism

Answer 42

energy-storing synthesis reactions requires energy input production of protein or fat

Question 43

# metabolism oxidation reduction catabolism and anabolism are

Answer 43

inseparably linked anabolism is driven by energy released by catabolism

Question 44

# metabolism oxidation reduction Oxidation

Answer 44

– A chemical reaction in which a molecule gives up electrons and releases energy – Molecule oxidized in this process – Electron acceptor molecule is the oxidizing agent * Oxygen is often involved as the electron acceptor

Question 45

# metabolism oxidation reduction Reduction

Answer 45

– Any chemical reaction in which a molecule gains electrons and energy – Molecule is reduced when it accepts electrons – Molecule that donates electrons is the reducing agent

Question 46

# Metabolism, Oxidation, and Reduction Oxidation-reduction (redox) reactions

Answer 46

– Oxidation of one molecule is always accompanied by reduction of another – Electrons are often transferred as hydrogen atoms

Question 47

# carbon compunds and functional groups carbon has 4 valence

Answer 47

electrons binds with other atoms that can provide it with 4 more electrons to fill its valence shell

Question 48

# carbon compunds and functional groups carbon atoms bind readily with

Answer 48

each other to form carbon backbones form long chains branched molecules and rings form covalent bonds with H, O, N, S carbon backbones carry a variety of functional groups

Question 49

# carbohydrates hydrophilic organic molecule

Answer 49

ex sugars and starches "saccar-" and "-ose" both meaning sugar and sweet

Question 50

# carbohydrates 3 important monosaccarides

Answer 50

glucose galactose fructose all isomers of each other produced by digestion of complex carbs

Question 51

# carbohydrates 3 important disaccharides

Answer 51

sucrose-table sugar lactose-sugar in milk maltose-grain products

Question 52

# carbohydrates 3 important ex of polysaccharides

Answer 52

glycogen- energy storage in cells of liver, muscle, brain, uterus, vagina starch- energy storage in plants that are DIGESTABLE cellulose- energy storage in plants that is important for human dietary fiber (INDIGESTABLE)

Question 53

Carbs are a quickly mobilized source of energy

Answer 53

All digested carbs converted to glucose Oxidized to make ATP

Question 54

Conjugated carb

Answer 54

Covalently bound to lipid or protein Ex glycolipids Glycoproteins Proteoglycans

Question 55

Glycolipids

Answer 55

External surface of cell membrane

Question 56

Glycoproteins

Answer 56

External surface of cell membrane Mucus of respiratory and digestive tracts

Question 57

Proteoglycans

Answer 57

More carb than protein Gels that hold cells and tissues together Gelatinous filler in umbilical cord and eye Joint lubrication and cartilage texture

Question 58

Lipids are

Answer 58

Hydrophobic organic molecules with a high ratio of hydrogen to oxygen Have more calories per gram than carbs

Question 59

5 primary lipids

Answer 59

Fatty acids Triglycerides Phospholipids Eicosanoids Steroids

Question 60

Fatty acids

Answer 60

Chains of 4-24 carbon atoms with carboxyl group on one end and methyl group on the other –Saturated fatty acids have a lot of hydrogen –Unsaturated fatty acids contain some double bonds between carbons in chain (potential to add hydrogen) •Polyunsaturated fatty acids have multiple double bonds between carbons in chain –Essential fatty acids must be obtained from food

Question 61

Triglycerides

Answer 61

Three fatty acids linked to glycerol –Each bond formed by dehydration synthesis –Broken down by hydrolysis

Question 62

Triglycerides at room temperature

Answer 62

–When liquid, called oils •Often polyunsaturated fats from plants –When solid, called fat •Saturated fats from animals

Question 63

Triglycerides primary function

Answer 63

energy storage –Also help with insulation and shock absorption (adipose tissue)