BIO 203 Exam 1- Miami University

biology

study of life

cell

basic building block of life, fundamental to biology, simplest unit of living matter

cell theory

idea that all living things are composed of cells, cells are the basic units of structure and function in living things, and new cells are produced from existing cells

- schledian, schwann and virchow

prokaryotic cells

no membrane bound organelles, DNA not enclosed in membrane (clustered in nucleoid), unicellular, no internal membranes

eukaryotic cells

live independently or multicellular, membrane bound nucleus, variety of organelles

nucleus

enclosed by double membrane (nuclear envelop), contains most of cells DNA in the form of chromosomes

mitochondira

enclosed in 2 membranes, produces majority of ATP, contains its own DNA, reproduce by division, thought to have evolved from bacteria

Endoplsmic Reticulum (ER)

complex of membrane bound compartments, synthesizes most cell membrane components and materials for export

Golgi apparatus

stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum

lysosomes

small, irregular shape, membrane bound, intracellular digestive system, acidic interior to recycle old cell partss

Perioxisomes

small and membrane bound, hydrogen peroxide used to inactive toxic molecules

transport vesicles

small and membrane bound, move materials between membrane bound compartments

Endocytosis

movement into the cell through transport vesicle

Exocytosis

movement out of the cell through vesicles into the outside environment

cytosol

inside the plasma membrane but outside the organelles, gel-like

cytoskeleton

protein filaments that provide shape and aid in movement

actin filaments

thin and abundant, cell movement and contraction (large numbers in muscle cells)

microtubules

thickets, hollow tube, guide movement of intracellular components, form the network from chromosomes segregation during cell division

intermediate filaments

strengthen cell

plastids

double-membraned organelles that function in photosynthesis, storage, or pigmentation in plant and algal cells

chloroplasts

large green organelle, surrounded by 2 membranes, internal stacks of membranes that contain chlorophyll, contain its own DNA, reproduce by division

photosynthesis

use of energy of sunlight to produce sugar

vacuoles

fluid filled allowing cell to become more rigid, storage and provide turgor

atom

simplest unit of a chemical element that can not be broken down

covalent bond

sharing of outer shell electrons

ionic bond

transfer of electrons in outer shell

electronegativity

measure of the tendency of an atom to attract a bonding pair of electrons

non polar

equal sharing of electrons

polar

unequal sharing of electrons

hydrogen bonds

Very weak bonds; occurs when a hydrogen atom in one molecule is attracted to the electrostatic atom in another molecule

hydrophobic

uncharged non polar molecule

hydrophilic

polar, charged attracted to water

unaggregated state

water population high ordered and low entropy, energetically unfavorable

aggregated state

water population low order and high entropy, energetically more favorable

carbon skeleton

carbon ability to form strong covalent bonds with other carbon atoms to form chains, branched tress and rings

organice compound

contains carbon bond, usually hydrophobic

functional groups

the components of organic molecules that are most commonly involved in chemical reactions, different groups have different properties

4 biological macromolecules

polysaccharides, proteins, fats and nucleic acids

sub unit of carbohydrates

sugars (monosaccharides)

sub unit of fats

fatty acids

sub unit of protiens

amino acids

sub unit of nucleic acids

nucleotides

condensation reaction

dehydration synthesis, linking of subunits together, produces a water molecule, forms covalent bond between subunits

hydrolisis reaction

splitting of macromolecules into subunits, splits water molecule

Carbohydrates

energy storage

polysaccharides

long term energy storage

Monosaccharides

short term energy storage, hydrophilic and polar (dissolve well in water)

isomers

same structural, but different organization of atoms in a ring

aldoses

double bonded oxygen at the end of the chain

ketoses

double bonded oxygen in middle of the chain

sugar derivatives

the hydroxyl groups of a simple monosaccharide, such as glucose, can be replaced by other groups

glucose + glucose

maltose

glucose + galactose

lactose

glucose + fructose

sucrose

cellulose

present in plants, cant be digested by humans, has a 1-4 beta linkage

glycoproteins and glycolipids

cell membranes of animal cells, most likely hydrophillic

lipids

Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen.

fatty acid

long chain of fatty-acids, carboxyl group, hydrophilic head, hydrophobic tail

unsaturated

1 or more double bonds (oils)

saturated

no double bonds, as many H+ ions in between carbons as possible

triglycerides

very long term energy storage, insulation, 3 fatty acids and glycerol covalently bonded

phospholipids

glycerol, 2 fatty acids and one polar phosphate group, ampipathic

phospolipid bilayer

A double layer of phospholipids molecules that is the primary component of all cellular membranes, heads face water and tails towards inside, regulate fluidity of membrane by changing double bonds in fatty acids

waxes

long chain fatty acids linked to long carbon alcohols or carbon rings, form soft/solid masses

lipids without fatty acids

- sterols

- biological membranes

- hormones

- vitamins

protein functions

- enzyme

- structural

- transport

- motor

- storages

- signal

- receptor

- gene regulatory

amino acid

Building blocks of protein, carboxyl acid group, H and R-group that determines type of amino acid

peptide bond

links carboxyl group to amino group, polar bonds

polypeptide

unbranched chain of amino acids

protein

folded, functional unit, may consist of one or more polypeptides

protein structure

stable and unique for each protein, structure derives functions, specified by sequence of amino acids

primary structure

sequence of amino acids

secondary structure

Either an alpha helix or beta pleated sheet.

tertiary structure

organization of regions of secondary structure in space, 3D confirmation (if only 1 polypeptide, final form)

quaternary structure

final 3D conformation of proteins consisting of more than one polypeptide

homodimer

2 identical subunits

heterodimer

2 different subunits

homotetramer

protein composed of four identical subunits

heterotrimer

a protein made up of four non-identical polypeptide chains

heteromeric

Term used to describe a protein that consists of two or more non-identical subunits (the Greek hetero prefix meaning 'other', the opposite of homo).

protein domains

segmetns of polypeptides that fold into compact, stable structures, usually carry out specific functions

protein families

related by evolution by structure or function, proteins assemble in large complex structures (dimer, helix, ring etc)

protein folding

occurs during synthesis and or transport across membrane but can fold afterward, starts to assume structure as protein exits the ribosome

spontaneous folding

when placed in urea, protein unfolds because urea creates H bonds, becomes a denatured protein

chaperones

Proteins that assist in protein folding during posttranslational processing, prevent proteins from leaving the "on path" track

molten globule

Intermediate states in the folding of a protein, close to final form, but different

diseases of misfolded proteins

-huntington, alzheimers, prion disease

hsp 70 family

during and after synthesis or during and after passage through membrane (during transportations), bind to exposed hydrophobic sections of protein & prevent protein from going down the wrong path

hsp 60 family

after synthesis or passage through membrane, provides space for protein to fold by its self then released back into the cytoplasm

proteasome

multicellular structure, made up of rings, recognizes misfolded proteins and brings them into the chamber to be broken up

how are proteins marked for destruction

1. addition of polyubiquitin chain

2. recognized by proteasome cap

3. taken into chamber

4. amino acids and ubiquitin molecule broken down and recycled

Ubiquitin-Conjugating System

1. ubiquitin activating enzyme covalently binds to UB and transfers it to the primers UB ligase

2. UB ligase binds to target

3.transfer of UB to misfolded protein ( has exposed hydrophobic sites)

4. cycle repeats until poly ub chain

5. target protein w/ poly ub chain goes to proteasome

- min of 4 ub attached to be destructed

ubiquitin activating enzyme

-E1

-activates the ubiquitin floating around in the cytosol in an ATP-dependent manner

- hydrolyzes ATP --> AMP

ubiquitin ligase

adds ubiquitin to misfolded protein

base

ends in -ine (adenine, guanine)

nucleoside

base + sugar

- ends in -ine (adenosine, guanosine)

roles of nucleotides

1. energy currency (ATP- short term)

2. coenzymes

3. intracellular messengers

4. components of nucleic acdis

energy currency

ATP (adenosine triphosphate), comes from food or sunlight

very long term energy storage

fatty acids

long term energy storage

glycogen