Biological Molecules and Biochemistry Practice Flashcards

Flashcards covering Biological Molecules including biochemistry basics, water properties, carbohydrates, proteins, lipids, and nucleic acids based on lecture notes.

Biomolecules

Molecules that are found in living organisms, including carbohydrates, lipids, proteins, and nucleic acids.

Bioelements

The 25 elements found in living organisms, 16 of which are found in humans.

Major Bioelements

The six elements that make up $99\%$ of bio-matter: Oxygen, Carbon, Hydrogen, Nitrogen, Calcium, and Phosphorus.

Minor Bioelements

Elements making up $1\%$ of bio-matter, including Potassium (K), Sulfur (S), Chlorine (Cl), Sodium (Na), and Magnesium (Mg).

Trace Bioelements

Elements making up $0.01\%$ of bio-matter, including Iron (Fe), Copper (Cu), Manganese (Mn), and Zinc (Zn).

Condensation (Dehydration Synthesis)

The process where monomers join to form a polymer, leading to an increase in weight and the formation of water ($n-1$ molecules, where n is the number of monomers).

Hydrolysis

The process where a polymer is broken down into monomers by adding water.

Specific Heat Capacity of Water

The energy required to raise the temperature of $1\,g$ of water by $1^\circ C$, which is $4.184\,J/g^\circ C$.

Heat of Vaporization of Water

The energy required to convert liquid water into gaseous form, which is $574\,cal/g$, helping to maintain temperature.

Cohesion

The attraction between two of the same molecules, such as between water molecules.

Adhesion

The attraction between a molecule and a surface, facilitating transport in the xylem.

Hydrophobic Exclusion

The reduction of contact area between water and hydrophobic substances, which maintains the integrity of the cell membrane.

Monosaccharides

The simplest carbohydrates (monomers) that are sweet, soluble in water, and cannot be further hydrolyzed; they exhibit stereoisomerism.

Aldose

A monosaccharide where the carbonyl group is an aldehyde located at the $C-1$ position.

Ketose

A monosaccharide where the carbonyl group is a ketone located at the $C-2$ position.

Furanose

A $5$-member ring structure of a sugar.

Pyranose

A $6$-member ring structure of a sugar.

Anomeric Carbon

The carbon in a ring structure derived from the carbonyl carbon ($C-1$ for Aldehydes, $C-2$ for Ketones).

Maltose

A disaccharide composed of two $\alpha$-glucose units linked by an $\alpha-1,4$ glycosidic bond.

Sucrose

A non-reducing disaccharide known as table sugar, composed of $\alpha$-glucose and $\beta$-fructose linked by an $\alpha-1, \beta-2$ glycosidic bond.

Lactose

Known as milk sugar, a disaccharide consisting of $\beta$-glucose and $\beta$-galactose.

Amylose

A linear polymer of $\alpha$-D-glucose with $\alpha-1,4$ glycosidic bonds making up $20-30\%$ of starch; it is soluble in hot water.

Amylopectin

A branched polymer of $\alpha$-D-glucose with $\alpha-1,6$ glycosidic bonds making up $70-80\%$ of starch; it is insoluble in water.

Cellulose

A structural polysaccharide in plant cell walls made of $\beta$-D-glucose units with $\beta-1,4$ glycosidic linkages in a criss-cross pattern.

Chitin

A structural polysaccharide found in the cell walls of fungi and the exoskeletons of animals, made of N-acetyl glucosamine.

Primary Structure

The linear sequence of amino acids in a polypeptide chain.

Secondary Structure

The coiling or folding of a polypeptide chain, such as the $\alpha$-helix (with $3.6$ amino acids per turn) or $\beta$-pleated sheet, stabilized by hydrogen bonds.

Tertiary Structure

The complex folding of a polypeptide into a 3D shape, stabilized by ionic, disulfide, and hydrogen bonds.

Quaternary Structure

The structure resulting from the aggregation of two or more polypeptide chains, such as in Haemoglobin.

Saturated Fatty Acids

Fatty acids containing only single bonds between carbon atoms, such as Palmitic acid ($16C$) and Steric acid ($18C$).

Unsaturated Fatty Acids

Fatty acids containing double or triple bonds, such as Oleic acid ($18C$), Linoleic acid ($18C$), and Linolenic acid ($18C$).

Phospholipids

Amphipathic molecules derived from phosphatidic acid with a polar head and non-polar tail, often containing choline, ethanolamine, inositol, or serine.

Terpenoids

Lipids made of isoprenoid units, including terpenes (e.g., Vitamin A), steroids (e.g., cholesterol), and carotenoids.

Prostaglandins

Lipids derived from arachidonic acid ($20:4$) that act as local hormones involved in fever, inflammation, and pain.

Nucleoside

A molecule consisting of a pentose sugar and a nitrogenous base.

Nucleotide

The monomer of nucleic acids, consisting of a nitrogenous base, a pentose sugar, and a phosphate group joined by phosphodiester bonds.

Purines

Double-ringed nitrogenous bases including Adenine ($6$-aminopurine) and Guanine ($2$-amino-$6$-oxypurine).

Pyrimidines

Single-ringed nitrogenous bases including Cytosine, Thymine ($5$-methyluracil), and Uracil.

Chargaff's Rule

The DNA base-pairing rule stating that the amount of Adenine equals Thymine ($A=T$) and Cytosine equals Guanine ($C=G$).

Glycolipid (Cerebrosides)

A conjugated molecule found in the myelin sheath and white matter of the brain, composed of a ceramide (FA + Sphingosine) and a hexose sugar.