11 ib bio exam hl

capillary action

the movement of water through a narrow passageway often in an opposing direction than the force of gravity

adhesion

the attraction of water molecules to other polar or charged molecules.

solvation

the interaction between a solvent and its dissolved solute

buoyancy

the upward force applied to an object when immersed in a liquid

• if the force of the liquid is greater than the object, it will be buoyant and float

viscosity

the measure of the tendency of a liquid to flow

cause: the effect of the friction of the liquid molecules as they slide over each other

effect: the efficiency of transport in the liquid

specific heat capacity

the quantity of heat energy needed to raise the temperature of a chemical per unit mass

osmolarity

refers to the concentration of solute particles in a solution measured in osmoles per liter

isotonic

have equal solute concentrations

four major classes of compounds in living organisms

• lipids

• proteins

• carbohydrates

• nucleic acids

monomers

• the basic building block molecules that are capable of being linked together to form larger structures

  • relativiely small compared to macrmolecules

  • can from chemical bonds w other monomer to form a chain

  • combines through condensation reactions to create biological polymers

examples: nucleotides, monosaccharides, amino acids

polymers

large molecules that are composed of repeating monomers

• examples: nucleic acids, polysaccharides, polypeptides

• macromolecules made from many monomers that can serve various biological functions

condensation reactions

• build complex molecules such as building polymers from monomers

• requires energy input

• is an anabolic process

• produces water as a byproduct

• utilizes enzymes that are catalysts and lower the activation energy

hydrolysis reaction

• the process of breaking down polymers into monomers by adding water

• releases energy and is a catabolic process

• exergonic — releases more energy than they use in the process

• provide energy that the cells requires for cellular work

monosaccharides

• the simplest carbohydraters consisting of singular sugar units that cannot be hydrolyzed into smaller carbohydrate molecules

• ranging from 3 to 7 carbons

cellulose microfibrils

• due to the hydroxyl groups of the glucose it can form hydrogen onds with neighboring chains and holding chains firmly together

• creates side-by-side structures called microfibrils

• makes up a rigid fiber structure in the cell wall

triglyceride

a glycerol molecule bonded to three fatty acid chains

• fats and oils

generalized structure of a fatty acid

~12-20 carbon atoms in a hydrocarbon chain and a carboxyl group at one end

essential amino acids

• the nine amino acids that are vital for human functions however we do not synthesize individually

• therefore, must be ingested from food because human metabolism alone is insufficient for what is needed

non-esssential amino acids

• the eleven amino acids that we can synthesize from other compounds, including other amino acids, carbs and fats

• we have the metabolic machiney to produce these on our own though

dipeptide

• a simple peptide bond molecule consisting of exactly two amino acids joined by a singular peptide bond

oligopeptide

• consists of 3-20 amino acids linked together by peptide bonds

  • representing short chains that serves as hormones, neurotransmitters, or signaling molecules

polypeptide

• a long chain of amino acids, typically consisting of more than 20 amino acids linked together by peptide bonds, and can fold into functional proteins.

• enable the diverse functions of proteins in living systems

location of cell polypeptide formation

• occurs in the ribosomes during protein synthesis, where amino acids are assembled into polypeptides based on mRNA sequences.

backbone of a polypeptide

• composed of a repeating sequence of peptide bonds linking amino acids, providing the structural framework for the polypeptide.

• excludes the R-groups

protein conformation

• the specific three dimensional shape of a protein molecule

• its most biologically active

• vital for protein function

primary structure

• the unique sequence of amino acids in a polypeptide chain, which determines the protein's specific properties and functionality.

  • involves transcription, translation, protein

secondary structure

• the local folding patterns of a polypeptide chain, commonly including alpha helices and beta sheets, stabilized by hydrogen bonds between backbone atoms.

• does not involve the R-groups

tertiary structure

• the overall three-dimensional shape of a protein that results from the interactions between the R groups of amino acids.

• crucial for the protein's functionality and stability.

• involves

  • H-bonds (for polar R-groups)

  • ionic bonds (for charged ions)

  • disulfide covalent bonds (cysteine amino acids)

  • and hydophobic interactions (for non-polar R-groups)

quaternary structure

multiple polypeptide chains that associate to form a single functional protein complex

non-conjugated protein complex

• folded polypeptides without any additional chemical groups attached

• derive all their structural and functional properties from the 20 standard amino acids and their various interactions

• performs diverse functions

conjugated proteins

• contain one or more non-protein components called prosthetic groups

  • metal ions

  • organic molecules

  • carbohydrate groups

  • lipid groups

possible modifications of polypeptides to form functional protein

• proteolysis; breaking of polypeptides through hydrolysis of peptide bonds

• phosphorylation: movement of phosphate group to protein

• glycosylation: adding carbohydrate chain to protein

• ubiquitination: attachment of small protein callled ubiquitin which acts as a destroy signal

• lipidation: a lipid molecule is attached to a protein