premed

Cisternae

Flattened and folded membranes that makes the golgi complex and endoplasmic reticulum

Ionic bonds

Two atoms, one metal and one nonmetal. One or more valance electrons are transferred from the metal to the non metal. The atom that loses the electron becomes a cation (positively charged ion) and the one that gains the electron becomes an anion (negative ion) each of them have a noble gas configuration

Octet rule

Atoms tend to have 8 electrons in the valance shell

Lewis structure

Valance electrons are represented by dots

Metallic bonding

Two metal atoms bond by releasing their valance electrons and creating a sea of electrons. Positively charged metal ions are created and are attracted to the sea of electrons forming a metallic bond

(Non polar) covalent bond

Two non metal atoms bond, instead of donating an electron from one to the other they share one or more valance electrons making the two atoms connect and form a molecule (neutral)

Polar covalent bond

Same as a regular covalent bond where the two atoms share the valance electrons instead of donating them from one to the other. But in a polar covalent bond the bonding electrons spend more time near the atom with the more electronegativity. Giving the bond a semi positive and a semi negative half (the negative half in the atom that is more electronegative because the electrons are more attracted to it)

Bond length

The distance between the 2 nuclei of the atom in a bond

Bond energy

The energy needed to break a bond in the gaseous state (kj/mole)

Coordinate covalent bond (subtype of covalent bond)

In a regular covenant bond valance electrons are shared (one from each atom). In a coordinate covalent bond one atom shares both valance electrons

A double covalent bond

Two pairs of electrons (4) are shared by two atoms.

(Mostly in c,n,o,s atoms)

A triple covalent bond

Three pairs of electrons (6) are shared by two atoms

Example- ethyne, mostly common in c and n atoms

Dipole moment

in a polar covalent bond If an atom has more electronegativity than the other the electrons will all be drawn to the atom with more electronegativity making one atom semi positive (because the electrons moved away from it) and making the other atom semi negative (because the electrons moved towards it)

Intermolecular bonds

Attracting forces between neighboring molecules. Normally much weaker than intramolecular bonds.

Van der wales forces

Weak attractive forces between molecules in a large number of substances. included dipole dipole and London forces

Dipole dipole forces

In dipole moment we said that in a polar bond the atom that has more electronegativity will attract the electrons of the less electronegative atom making a semi positive side and a semi negative side.

So a dipole dipole force refers to the tendency of polar molecules to align themselves so the positive end of a neighboring molecule is near the negative end of another and opposite.

When the electrons moved and created a semi positive side in the atom that’s less electronegative neighboring polar molecules will be attracted to the atom’s semi positive side making a weak bond called dipole dipole

London forces

Occurs randomly and temporarily in non polar molecules or noble gasses because of the electrons constant movement creating a temporary dipole when the electrons are on one side (as a part of their spinning) and a temporary semi positive side is created and a neighboring molecule’s electrons are attracted to the positive temporary side creating a London force

Cargo complex

Contains the importin (carrier protein) and the protein with the nuclear localization signal

Importin

Carrier protein that carries proteins that has a nuclear localization signal through the pores of the nuclear envelope

Histones

Complex protein that DNA wraps around to make chromatin creating chromosomes

endosymbiosis

Because mitochondria and prokaryotic cell both contain their own genome and have circular DNA it is believed that mitochondria and chloroplast evolved from prokaryotic cells that took residence in eukaryotic cells.

Molecular chaperones

Type of enzymes in the endoplasmic reticulum that assists folding proteins

Apoptosis

Planned cellular death, takes place in normal development. E.g. when cells die to create the space between fingers

Phagocytosis

When a cell is consumed by another cell (eaten)

Necrosis

Unplanned cellular death that causes inflammation and might damage other cells.

Endoplasmic reticulum

Made out of Cisternae.

Rough endoplasmic reticulum- ribosomes on surface creating proteins. The proteins get folded by molecular chaperones and go through initial modification then get sent away by vesicles to the golgi.

Smooth endoplasmic reticulum- make lipids, breaks carbs, breaks poisons (in liver cells) by adding hydroxyl groups

Magnetic quantum number

(ML) represents the orientation of an orbital in space. Does not affect energy. (ML= -L…0…+L)

Number of optional ML = number of orbits

Spin quantum number

(Ms) represents the possible orientation of electrons

-1/2 against the clock

+1/2 clockwise

Principle quantum number

(N) can be 1-7

The larger n is the larger the orbital and the larger the electron’s energy.

Angular momentum quantum numbers

(L) shape or volume of space that the electron occupies, larger l = larger energy of an electron

We have 4 sub shells.

s- circular shape - L=0 - contains 2 electrons max

P- dumbbell shape- L=1- contains 6 electrons max

D- four circles- L=2 - contains 10 electrons max

F- flower shape- L=3- contains 14 electrons max F

First shell- s | second shell- s+p| third shell-s+p+D|

Fourth shell-S+p+d+f

Jj Thompson

jj Thompson discovered electrons.

He used a glass tube and two electrodes, one positively charged (anode) and one negatively charged (cathode) and a negatively charged plate and a positively charged plate.

When high voltage current was on he could see a green light, he saw that the green light (negatively charged particles) was attracted to the positively charged plates (opposites attract) and he discovered the negatively charged particles called electrons.

Milikan

Milikan sprayed oil into a chamber above negative and positive charged plates. The oil drop caught electrical charge from the friction.

By adjusting the voltage on the plates he could make the oil float up and down. He noticed that whenever a drop gained or lost charge it was always a specific amount.

meaning electrical charge can only be increased or decreased by a certain amount each time and he managed to measure the charge of an electron

Rutherford

Released positive alpha particles and put a gold foil in the middle, the alpha particles met the golden foil in the middle and only repelled occasionally. (Only when they met the golden foil’s nucleus that was also positively charged)

he reached the conclusion that an atom is mostly empty space (because the particles rarely repelled) and that the only positive thing in the atom is the nucleus that’s a very small part of the atom

Cytoplasm

All matter within the cell excluding the nucleus (organelles + cytoplasm)

Cytosol

Cellular fluid

Nucleoplasm

Liquid within the nucleus

Endomembrane system

Membranes in the cytoplasm that divide the cell

Pili

Hair like, responsible for attachment, antigenic (recognized foreign by our immune system)

Only in prokaryotic cells.

Vacuol

Found in all plants and fungal and some animals, lined with membrane and filled with fluid.

Holds supplies of water, inorganic ions, amino acids, and sugars. The membrane in a vacuol in plants and fungal is called tonoplast

The perinuclear space

The space between the inner and outer membranes of the nuclear envelope. Continues with the rER lumen.

Prokaryotic cells

Found only in unicellular (one cell) organisms like bacteria and archaea. Lack a nucleus and membrane bound organelles , instead of a nucleus they have nucleoid area where their DNA is instead. contain circular DNA instead of linear.

Vesicles

Membrane bound sacks enclosed by a lipid bilayer. Carry proteins, lipids and other molecules to different locations within the cell. fuses with plasma membrane to release materials. or bring them into the cell by pinching a piece from the membrane. Uses the cytoskeleton as tracks.

Peroxisomes

Small membrane bound organelle found in the cytoplasm of all eukaryotic cells.breaks down fat acids, amino acids, alcohol and hydrogen peroxide.

also creates hydrogen peroxide and it is packed with enzymes.

Cis face & trans face

Both in the golgi complex,

the cis face is responsible for receiving the proteins that needs modification from vesicles.

The trans face sends the mature protein after they had been modified out of the Golgi complex

Free ribosomes

Float in the cytosol and produce proteins for use within the cell

Bound ribosomes

Attached to the rough endoplasmic reticulum, make proteins for export out of the cell

Nucleolus

not enclosed by a membrane, contains a nucleolar organizer region (NOR) made from DNA and is used for making ribosomal rna (rRNa) inside the nucleolus

Nuclear lamina

Fibrous network of protein filaments, found in the inner lining of the nuclear envelope and regulates cellular events such as DNA replication and cellular division, participates in chromatin organization

Sex pili

Allows the transfer of DNA between bacteria during the process of bacterial conjunction. Only in prokaryotic cells.

Capsule

Found in prokaryotic cells, the outermost layer. Protects from phagocytosis (to be consumed by another cell)

Flagella

Found in prokaryotic cells, long, whip shaped composed of protein complex. Responsible for cellular locomotion (movement) .

Extensive properties

Properties that are proportional to the size of the sample, (if sample grows properties grow too)

E.g. - mass, weight

Intensive properties

Independent from size (if sample grows properties don’t grow accordingly)

E.g. color, smell, temperature

Amphilipic

Both hydrophilic and hydrophobic at the same time, for example phospholipids

Atomic radius

The distance from the nucleus to the outer edge of the electron cloud in the atom. The more it’s down and to the left on the periodic table the bigger the atomic radius is.

2 factors-

N number

Protons number increase = atomic radius decrease

Ionization energy

Minimal energy to remove the highest energy electron from a neutral atom is the gaseous state

Electron affinity

The energy charge required for the process of adding an electron to a neutral atom in the gaseous state to form a negative charged ion.

Measured in J/mol either + or -

The more negative an ion is the more in is stable

Electronegativity

The tendency of an atom to attract the bonding electrons to itself.

Bonding electrons- valance electrons shared between 2 atoms to create a chemical bond and form a molecule

Bonding electrons-

valance electrons shared between 2 atoms to create a chemical bond and form a molecule