Atoms to Compounds & Biomolecules Lecture

Practice flashcards covering atoms, chemical bonds, water functions, carbohydrates, lipids, nucleic acids, and protein structures based on Lecture 1 notes.

Prokaryote

An organism that has NO nucleus.

Eukaryote

An organism that HAS a nucleus.

Atom Structure

Consists of a nucleus (protons + neutrons) and electrons.

Molecule

Two or more atoms joined together.

Compound

Two or more DIFFERENT elements joined together.

Dalton

A unit of atomic mass ($≈$ mass of one proton/neutron).

Radioactive isotopes

Tracers that the body CANNOT distinguish from non-radioactive ones, allowing them to be absorbed directly into the blood.

Octet rule

The principle that elements seek to complete their valence shell because they have unfilled outermost shells.

Organic compounds

Compounds that are carbon-based.

Inorganic compounds

Compounds such as salts ($NaCl$) and water ($H_2O$).

Water Functions

1. Lubricates joints (synovial fluid); 2. Allows lung recoil (pleural fluid); 3. Cushions the brain (cerebrospinal fluid); 4. Heat sink and universal solvent.

Monosaccharide

A single sugar unit, such as glucose, fructose, or galactose.

Disaccharide

Two sugar units joined together, such as lactose, maltose, or sucrose.

Oligosaccharide

A carbohydrate consisting of a few sugar units.

Polysaccharide

A carbohydrate consisting of many sugar units, such as glycogen, cellulose, or chitin.

$α$-anomers

Sugar forms that humans CAN digest, such as maltose and glycogen.

$β$-anomers

Sugar forms that humans CANNOT digest, such as cellulose.

Reducing sugar

A sugar with a free aldehyde or ketone group that can donate electrons.

Glycogen

A branched polysaccharide used for short-term energy storage.

Cellulose

A structural carbohydrate ($β$-glucose) that aids digestion in humans but from which we CANNOT extract energy.

Chitin

A polysaccharide found in the exoskeletons of insects and fungi.

Sorbitol

A sugar alcohol used in diabetic foods and as a laxative.

Gluconic acid

The oxidized form of glucose.

Glucuronic acid

A sugar derivative involved in detoxification in the liver.

Lactose intolerance

A lactase deficiency where undigested lactose causes osmotic diarrhea, gas, and bloating.

Secondary lactase deficiency

Lactase deficiency caused by other conditions like celiac disease, Crohn's, or gastroenteritis.

Excipient

An inactive filler used in medications, such as lactose.

Triglyceride (Triacylglycerol)

A lipid composed of 3 fatty acids + 1 glycerol used for energy storage.

Cis formation

A double bond that creates a BEND/kink in the fatty acid tail, making the membrane more FLUID.

Trans formation

A fatty acid structure with no bend, making it more rigid and similar to saturated fats.

Amphipathic molecule

A molecule that possesses both a hydrophilic head and a hydrophobic tail.

Phospholipid

A molecule composed of glycerol + 2 fatty acids + phosphate group + polar head, which forms the lipid bilayer.

Nucleotide

A building block of nucleic acids composed of 3 parts: a phosphate group, a sugar, and a nitrogenous base.

Nucleoside

A structure composed of only 2 parts: a sugar and a nitrogenous base.

DNA

A double helix structure using Deoxyribose sugar and bases $A, T, G, C$.

RNA

A single strand structure using Ribose sugar and bases $A, U, G, C$, and is missing one $-OH$ compared to DNA.

Mutagenic

Refers to anything that causes DNA mutations.

Transcription

The process of converting DNA to RNA occurring in the nucleus.

Translation

The process of converting RNA to Protein occurring at the ribosome.

$α$-carbon

The central carbon in an amino acid with 4 different groups attached, making it optically active.

Zwitterion

An amino acid that carries BOTH $+$ and $-$ charges simultaneously at physiological pH.

Peptide bond

The covalent bond that links amino acids together.

Primary Structure

The first level of protein structure, consisting of the sequence of amino acids linked by peptide bonds.

Secondary Structure

Protein folding into $α$-helices and $β$-sheets maintained by hydrogen bonds.

Tertiary Structure

The 3D folding of a whole polypeptide.

Quaternary Structure

The structure formed by multiple polypeptide subunits together.

Phosphorylation

The addition of a phosphate group to a protein to activate or deactivate it.