chapter 1 Flashcards
vacuole
an organelle that stores key molecules, prominent in most plant cells
ex) holds water molecules
chloroplast
an organelle that has the molecular machinery required for photosynthesis
cell wall
a stiff structure outside of cells, usually made of carbohydrates
endoplasmic reticulum (ER)
a eukaryotic organelle that forms a branching network of tubes and flattened sacs.
-Place where proteins, lipids, and other molecules are synthesized and processed
-can be rough or smooth
golgi
an organelle comprised of stacked, flattened sacs, where proteins and other molecules are processed and packaged for shipment to other locations
actin filaments
small diameter, cytoskeletal fibers made of subunits of the actin protein
intermediate filaments
cytoskeletal fibers whose size is intermediate between those of actin filaments and microtubes that are made from a variety of protein subunits
microtubes
large diameter, hollow cytoskeletal elements made of pairs of alpha and beta tubulin
cell membrane
lipid bilayer and membrane proteins with carbohydrates attached to both
regulates ions and molecules that come in and out of the cell
genetic material
heritable information present in one or more DNA chromosomes
ribosomes
protein-production factories
complex of RNA protein molecules and is the site where amino acids are linked by peptide bonds
mRNA
information messenger RNA
organelles
membrane-bound internal compartments that consist of a lipid bilayer studded with short carbs. that serve as zipcodes
inside of organelle are molecular machines that preform special tasks essential for cellular life
flagella
long, thin projections that extend far beyond the cell membrane and cell wall and propel the cell through water
nucleus
organelle unique to eukaryotes enclosed by a double membrane and containing cells chromosomes
mitochondrion
“powerhouse of the cell”
burns sugars to provide energy for the cell
eukaryote
species with cells that contain a nucleus and mitochondria
prokaryote
species in the lineages Archaea and Bacteria, cells that lack a nucleus
what do carbohydrates include
the building block of molecules called simple sugars as well as larger molecules made of sugars that are covalently linked to each other
monosaccharides
-simple sugars
-they include a chain of carbons, a carbonyl (C=O) group
-several -OH (hydroxyl) groups
monosaccharides can link together and form larger
carbohydrates
gylcan
formed when many simple sugars are linked to each other
glycosidic linkages
monosaccharides connect to form glycans via covalent bonds
phosphodiester linkages
nucleotides form nucleic acids via covalent bonds
peptide bonds
amino acids form proteins via covalent bonds
carbohydrate functions
-energy storage and processing
-structural support
-identification of cells and cell parts
(act as a “zipcode” in an organism)
glycan is made up of
monosaccharides joined by glycosidic linkages
what are some functions that can be carried out by a protein
-help start (or continue) biochemical reactions in cells
-provide support and structure for a cell
-transporting molecules in and out of the cell
functional groups involved in making a peptide bond
-an amine group and a carboxylic acid group
ex) (-NH2) and (-COOH)
if an amino group (-NH2) was removed, what processes would be affected?
-formation of peptide bonds
-formation of hydrogen bonds
what levels of protein structure are affected when a protein is denatured?
secondary, tertiary, quaternary
antibodies
help protect from infection
enzymes
allow organisms to extract energy from food and build biomolecules
peptide bonds
proteins form when amino acids link together via covalent bonds
with a carboxyl and amino groups
primary structure
the sequence of amino acids joined by peptide bonds linked in a chain
secondary structure and its 2 elements
-it is not a straight sequence of amino acids
-a-helix (barrel strands)
-b-pleated sheets (bent rectangle things)
in both a-helix and b-pleated sheets the hydrogen bonds form b/w…
partial charges on H and O atoms in peptide-bonded backbone
in a-helix, the R-groups that stick out side of the spiral
they are free to interact w/ other parts of the same protein or different molecules
R-groups
functional group that represents a group of atoms attached to a molecule by a hydrogen or carbon atom
the folds on a b-pleated sheet create…
secondary structure proteins that do not involve R-groups, only the atoms in the peptide-bonded backbone
in a ribbon diagram the arrowheads point
in the direction of the carboxyl end of the protein
four general categories if tertiary structures
1) hydrogen bonds b/w partial charges on N-H and C=O groups in peptide backbone and/or opposite partial charges on R-groups
2) Ionic bonds b/w full charges on R-groups
3) Covalent bonds b/w sulfur atoms in R-groups (disulfide bridges)
4) interactions between hydrophobic R-groups
what is the function b/w chaperon protiens
-since T-structures must be oriented in an exact way, chaperon proteins help support efficient folding
denaturation
the unfolding of proteins
quaternary structure
the final level of organization
-when folded subunits stick together
what are some of the functions of proteins (long list)
-catalysts (making chemical reactions go)
-transporting materials
-movements (especially in the muscle fibers)
-cell structure (component of skin, muscle, bone, cartilage, and tendons)
-defense
-signaling and communication
