Midterm 1 Flashcards
Protein Primary Structure
The order and type of amino acids bonded together to form the protein chain
Protein Secondary Structure
The coiled or folded patterns created by Hydrogen bonds on the amino acid backbones (not side chains)
can be beta-sheet or alpha helix structures
Protein Tertiary Structure
The overall 3D form of the protein created by interactions between side chain compounds on the amino acid backbone (the functional groups)
Protein Quaternary Structure
Some proteins associate closely and become entwined to create a larger functional protein (only sometimes)
Proteins
A chain of amino acids bonded together with peptide bonds. Each amino acid matters in the overall structure with different proteins having different orders
What determines protein structure
The given amino acid sequence, the interactions, other proteins and environmental factors
Protein Denaturation
Breakdown of proteins, losing their native shape becomes biologically inactive, can be caused by heat or chemical reactions
Macromolecules
large organic molecules
4 Classes of Macromolecules
Lipids, Carbohydrates, Proteins and Nucleic Acids
Polymer and Monomer
Polymer: many monomers joined by dehydration reactions
Monomer: smaller molecule, creates building blocks of larger ones
Polymer Synthesis
Dehydration reaction, H2O released and two monomers join
Polymer Breakdown
Hydrolysis, Adding water to molecule to break previous bond
Carbohydrates
Sugars, polymers of sugars
Monosaccharides
is a type of sugar, molecular formulas that are some multiple of the unit CH2O, Glucose is the most common, has a carbonyl group and a whole bunch of hydroxyl groups
Disaccharide
two monosaccharides joined
Glycosidic linkage
a covalent bond between two monosacc. by a dehydration rxn. happens between an exterior OH group on each molecule, they release H2O and leave an oxygen bonded to each in the middle
Polysaccharides
macromolecules, polymers with a shitload of monosacc’s joined by glycosidic linkages
Storage Polysaccharides
stored sugars for later use, plants store starch within cellular structures called plastids (like chloroplasts), animals use glycogen
Structural Polysaccharides
EG. cellulose, strong materials for use in things like plant cell walls, can link together to form fibres that are strong
Lipids
doesnt really include polymers, they are just mostly hydrophobic, not many other similarities
Fats
constructed from glycerol and three fatty acids ester linked to each of the three carbons in glycerol
Glycerol
Alcohol with three carbons each having a hydroxyl group
Fatty Acid
Has a long carbon skeleton, one end has a carboxyl group. Mostly hydrophobic because C-H bonds are not very polar
Ester linkage
dehydration rxn between hydroxyl group and carboxyl group
Saturated Fatty Acids
Fatty acid with no double bonds btwn carbon atoms, as many hydrogen atoms as possible are bonded to the carbon skeleton, tails are flexible and allw them to pack together tightly, are solid at room temp
Unsat. fatty acids
Fatty acids with one fewer hydrogen atom on each double bonded carbon atom, causes a kink in the fatty acid structure, means they are liquid at room temp
Phospholipid
similar to fat molecule but only has two fatty acids attahced to glycerol rather than 3, third is taken by a phosphate group which is polar
Phospholipid properties
one end is hydrophobic (tails) and one end is hydrophilic (phosphate “head”), when added to water they form a bilayer, the heads on the outside and the tails on the inside
Steroids
lipids with carbon skeleton consisting of four fused rings, distinguished by the particular chemical groups attached to these rings
Cholesterol
type of steroid, common component of animal cell membranes
Catalysts
chemicals that can speed up reactions without being consumed in the process
amino acid
contains an amino group (NH2) and a carboxyl group (COOH) bonded to a central carbon atom with a functional chain and a hydrogen bonded to it
alpha carbon
central carbon of an amino acid
Gene
programs the amino acid sequence of a protein, consists of DNA
Nucleic Acids
Polymers made of monomers called nucleotides
Types of nucleic acids
DNA and RNA
DNA
deoxyribonucleic acid
RNA
ribonucleic acid
Gene expression
DNA using RNA to control protein synthesis
Components of Nucleic Acids
polymers called polynucleotides, composed of nucleotides.
Each nucleotide consists of a five carbon sugar (pentose), a nitrogenous base (contains nitrogen) and one to three phosphate groups, two end up lost during polymerization
pyrimidine
one six membered ring of carbon and nitrogen atoms, Members are Cytosine (C), Thymine (T), Uracil (U)
Purine
Six member ring fused to a group tat links the sugars of two nucleotides, Adenine (A) and Guanine (G)
Only places Thymine is Found
DNA
Only places Uracil is Found
RNA
Adenine, Guanine, Cytosine is found?
DNA and RNA
Nucleotide Polymers
Page 133
DNA and RNA Structures
have two polynucleotides or “strands”. Wind around an axis creating a double helix. The two sugar phosphate backbones run in opposite directions (3’ and 5’) with the bases paired towards the interior of the structure, called antiparallel
Organelles
membrane bound structures within eukaryotes
Cytosol
semifluid jelly-like substance inside all cells, sub-cellular components are suspended inside
Stuff that all cells contain
Cytosol, Chromosomes, ribosomes
DNA in pro/eu karyotes
prokaryotes have DNA in a general region called the nucleoid, not membrane enclosed
Eukaryotes have it inside the nucleus
Cytoplasm
region between the nucleus and plasma membrane inside the cell
Size of cells
Eukaryotes are ususally much bigger than prokaryotes
Plasma membrane
selective barrier allowing passage of enough oxygen, nutrients etc to service cell
membranes
basic fabric of most is double layer of phospholipids and other lipids that have proteins embedded in one side or through both sides
each is unique
Flagellum
motility structure present in some aimal cells, composed of a cluster of microtubules within an extension of the plasma membrane
Centrosome
region where the cells microtubules are initiated, contains a pair of centrioles
centriole
helps organize the microtubules that serve as the cell skeleton
Cytoskeleton
reinforces cell shape, functions in cell movement, components are made of protein, parts include; microfilaments, intermediate filaments, microtubules
plasma membrane
membrane enclosing cell
peroxisome
various metabolic functions, produces hydrogen peroxide as a by product then converts it to water
ribosome
Complexes that make proteins; free in cytosol or bound to rough ER or nuclear envelope
Golgi Apparatus
active in synthesis, modificaiton, sorting and secretion of cell products
Lysosome
digestive organelle where macromoluecules are hydrolyzed (broken down)
ER
network of membranous sacs and tubes, active in membrane synthesis and other synthetic and metabolic processes. Has a rough section studded with ribosomes and a smooth section
Nuclear envelope
double membrane enclosing the nucleus, perforated by pores, continuous with ER, double membrane consists of two separate lipid bilayers with associated proteins, separated by a small space, perforated by pore structures that regulates entry and exit of RNA and proteins as well as macromolecules
Nucleolus
non-membranous structure involved in production of ribosomes, nucleus has one or more nucleoli
chromatin
material consisting of DNA and proteins, visible in a dividing cell as individual condensed chromosomes
Central vacuoule
prominent in older plant cells, functions include storage, breakdown of waste products and hydrolysis of macromolecules, enlargement of the vacuoule is major mechanism of plant growth
chloroplast
photosynthetic organelle, converts energy of sunlight to chemical energy stored in sugar molecules
nuclear lamina
netlike array or protein filament structures that help the nucleus maintain its general structure and shape, called intermediate filaments that maintain the shape of the nucleus by supporting the nuclear envelope
chromosomes
structures that carry genetic information, one long DNA molecule associated with the creation of many proteins.
ribosomes
complexes made of ribosomal RNAs and proteins are the cellular components that carry out protein synthesis (NOT MEMBRANE BOUND). (not considered organelles). More ribosomes= more proteins and tend to have larger nucleoli,
Free ribosomes
Free to move around in the cytoplasm, mostly make proteins for use in the cytoplasm
Bound ribosomes
bound to the Rough ER, functionally identical to the free ribosomes generally make proteins that are inserted into membranes or into digestive organelles like lysosomes or for export out of the cell (communication proteins)
ER
extensive network of membranes, consists of network of membranous tubules and sacs called cisternae, ER membrane separates internal compartment of the ER called the cisternal space from the cytosol
Smooth ER
outer surface of the ER that lacks ribosomes, functions with metabolic processes like synthesis of lipids, sex hormones. some enzymes it makes help to detox cells
Rough ER
inner surface studded with ribosomes, appears rough through the electron microscope, functions to
