Week 1 Cell Physiology - Atoms, Molecules, Bonding

Matter

anything that has mass and takes up space

Solid, Liquid, Gas, Plasma

What are the four states of matter?

Mass

is the amount of matter in a given object

Weight

is a measure of gravity's pull on an object

Volume

amount of space something occupies

Atoms

fundamental unit of matter; smallest particle of an element that retains characteristics of that element

Element

made up of only one type of atom

118

There are currently how many elements?

~40

Around how many elements are used in the makeup of the human body?

Hydrogen, Carbon, Nitrogen, Oxygen, Phosphorus, and Calcium

95% of the body is made up of 6 elements. They are:

Identity

The number of protons determines the _____ of an atom

Ion

If the number of electrons changes, an atom becomes a what?

2

The Level 1 (K) shell can hold _____ electrons

8

The Level 2 (L) shell can hold _____ electrons

18

The Level 3 (M) shell can hold _____ electrons

32

The Level 4 (N) shell can hold _____ electrons

s, 2

What orbital is this? How many electrons can it hold?

d, 10

What orbital is this? How many electrons can it hold?

p, 6

What orbital is this? How many electrons can it hold?

f, 14

What orbital is this? How many electrons can it hold?

Mendeleleev

Who created the periodic table?

118

How many elements are in the periodic table?

Atomic mass

Elements are placed in order of increasing _____ _____

Periods

horizontal rows of elements

Same energy level is being filled

Across a period, what remains the same in each element?

Groups

Vertical columns of elements

Same number of valence electrons

Down a group, what remains the same in each element?

Valence electrons

Electrons in the outermost shell

Cations

Positive ions are called

Anions

Negative ions are called

Gain

Nonmetals tend to _____ electrons (think fluorine)

Lose

Metals tend to ____ electrons (think Lithium)

Na+

Ion of biological significance; important in creating action potentials; drives movement of particles across membrane (ion exchange)

K+

Ion of biological significance; action potentials; graded potentials; water balance in the kidneys; reestablishment of resting potentials

Ca2+

Ion of biological significance; stored in bones; second messenger in cells; release of neurotransmitters; muscle contraction (part of sliding filament process)

Mg2+

Ion of biological significance; common cofactor in enzymatic reactions

Cl-

Ion of biological significance; major negative ion; used in action potentials

Transfer, sharing

Ionic bonds involve the _____ of electrons, while covalent bonds involve the _____ of electrons

Ionic bonds

an attraction between oppositely charged ions

Metals and Nonmetals

Ionic bonds form between _____ and _____

Lattice structure

a systematic, symmetrical network of atoms forming an ionic solid

Dissociate

Ionic compounds _____ in water

Electrolyte solutions

a solution that conducts electricity; is a solution with ions in it

It's polar

What property about water allows it to dissolve ions?

Nonmetals and nonmetals

Covalent bonds form between _____ and _____

Sigma bond

The strongest or most "perfect bond"

Pi bond

Exist in double bonds. 1 sigma and 1 pi bond

Weaker

1 Pi bond is (weaker or stronger) than 1 sigma bond

Single bonds

generally consist of sigma bonds

Double bonds

generally consist of 1 sigma bond and 1 pi bond

Typically made up of 1 sigma bond and 2 pi bonds

Acids

covalent compounds that produce H+ ions

hydrogen, anion

HCl, HNO3

Most acids contain a covalent bond between _____ and some stable _____

Electronegativity

"the ability of an atom to attract bonding electrons"

Fluorine

_____ is the most electronegative element

Pauling Scale

The _____ Scale gives electronegativity values between 0 and 4

Dipole moment

Covalent molecules have different geometries. Geometry can affect the _____ _____ of a molecule

nonpolar covalent bond

EN difference 0.0-0.4

polar covalent bond

EN difference is 0.5-2.0

ionic bond

EN difference is 2.0-4.0

Nitrogen, Oxygen, Fluorine, Chlorine

Physiologically important polar covalent bonds - an H or C bonded to what four elements?

Intramolecular forces

the force that binds one atom to another

Intermolecular forces

the forces that mediate interaction between molecules

Hydrogen bond

A H atom is covalently bonded to an electronegative N, O, F and that H interacts with a different N, O, or F

Weaker, longer

Hydrogen bonds are (stronger or weaker) and (longer or shorter) than covalent bonds

Hydrogen bonds

DNA is held together by what type of bond?

Salt bridge

describes ionic bonds within the same protein molecule

Dipole-Dipole

describes the attraction of neighboring polar groups to one another

London Forces (Van der Waals)

weak electrostatic interaction between all types of atoms

~3.4

An water molecule forms hydrogen bonds with ~_____ other water molecules

4

When water is frozen, each molecule forms _____ hydrogen bonds

Hydrophilic

"water loving"

Hydrophobic

"water fearing"

Hydrophobic effect

The tendency for nonpolar molecules to aggregate in water solutions; tends to occur in protein folding

Hydrophobic effect

Because of the _____ _____, ingested fat must be surrounded by polar/charged molecules for transport

Amphipathic molecules

Molecules that contain regions that are polar and regions that are nonpolar

Micelles

Thermodynamically stable structures of amphipathic compounds in wtaer

Hydrophobic

Enzyme bonding sites often have a (hydrophobic or hydrophilic) binding site. This site is perfect for things like steriods