Biology Gr 12

What are macromolecules?

They are biomolecules, large organic compouds essential for cell/organism life and have varying roles/properties. They are all polymers.

What are polymers?

They are complex molecules made from repeating monomers.

How are macromolecules produced?

Produced through dehydration synthesis rxn.

How are macromolecules broken down?

Through hydrolysis, catabolic rxn. Requires enzymes to happen efficiently.

What are isomers?

Compounds that have the exact same chemical formula but varying structural formula, grants difernt name and properties.

What is an anabolic rxn?

Smaller molecules and energy produce larger molecules

What is a catabolic rxn?

larger molecules —> smaller molecules + energy

How does carbon’s bonding capacity look like?

It’s tetravalent (4-bonds), can form chains, rings and sheets

What are carbohydrates? summary

Carbs are sugar polymers with hydroxyl groups that make them water soluable. Main functions include energy source (glucose) and energy storage (starch) and structural support (cellulose in plant cell walls)

What is the function of carbohydrates?

They act as a source of energy, building materials and as all surgace marker for cell to cell identification and communication.

How do you recognise carbohydrates?

They contain C:H:O atoms in a ration of 1:2:1 and are polymers, forming a long chain of subunits called monosacherides linked by glycoslic bonds.

What are lipds? Summary

Lipids are non-polar, hydrophobic molecules that store long-term energy, provide insulation and waterproofing, form builiding blocks of hormones, and make up the bilayer of cell membranes.

What is the function of lipids?

They serve as long-term energy storage, insulation, and are the building blocks of hormones, and vitamin storage (many vitamins are fat soluable) and form cell membranes of all cells.

How do you recongise lipids?

held together by ester bonds, limited oxygen atoms in compare to carbs, long carbon chain

What are proteins? summary

proteins are amino-acid polymers with peptide bonds recognise by their amino and carboxyl groups and 3d shape. they do almost everything in cells—enzymes catalyse rxn, hormones signal, and structural proteins build and support the body.

what is the function of proteins?

They transport, storage, defense, hormones, structural building. each type of protein has its unique function.

What is the function of digestive enzymes?

They break down food into monomers (eg.g amalyase, pepsin, and trypsin)

What is the function of transport proteins?

They carry substances in the blood/lymph. (eg. hemoglobin, albumin)

What is the function of structual proteins?

They build structures like the cytoskeleton(eg. actin, tubuli, keratin)

What is the function of hormones proteins?

They coordinate the body systems activtity(e.g. insulin, and thyroxine)

What is the function of defense proteins?

They protect against pathogens (e.g. immunogloulins)

What is the function of contractile proteins?

They aid in muscle contraction (e.g. actin, and myosin)

What is the function of storage proteins?

They nourish embro=yos and seedlings (eg. eggwhite (albumin))

How to recognise proteins?

They are polymers with the repeating submit called amino acids which are linked for peptide bonds. there are 20 various types of amino acids with varying properties

How are macromolecules formed?

Through condensation rxn (removing water)

How are macromolecules broken down?

Via hydrolysis (adding water)

What are nucleic acids? summary

nucleic acids are nucleic polymers (phphate + sugar + nitrogenous base ) recognised by phosphate groups and dna/rna structure. they store genetic info (dna) and direct protein synthesis (rna), essentially carrying instruction for life.

What is the function of nucleic acids?

They are most vauable for the continuity of life, carrying the genetic blueprint fo tthe cell. the dna stores genertic info which is passed down generations while the rna carries instruction from dna to make proteins and helps carry out instruction, direcgting protein sysntheiss to ribosomes to build proteins via transcription and translation

How to recognise nucleic acids?

They are made of three aprts: phosohtate group, pentose (5-C) sugar and nitrogenous base. The function group is (-PO4), which grants the polar property.

What is a methyl group, properties, and example?

Non-polar, hydrophobic, held together by london forces, not very reactive

(e.g. basically all organic commpounds)

What is a hydroxyl group, properties, and example?

polar, hydrophillic, strong IMF (dipole dipole + h-bonding) e.g. carbs, glucose and alcohol

What is a carboxyl acid group, properties, and example?

Acidic group, release H+ ions, ionised in solution and engage in h-bonding to accept h+ ions, polar, hydrophillic, engages in h-bonding and dipole dipole (e.g. amino/acetic acid)

What is a amino group, properties, and example?

can become charged, basic, polar, dipole dipole and h-bonding, eg. amino acid and amines

What is a sulfhydryl group, properties, and example?

e.g. amino acid, it is polar, forms disulfide bonds, help stabilise protein structure,(longdon london , dipole dipole)

What is a phosphate group, properties, and example?

(e.g. ATP, dna/rna backbone structure) it is polar, acidic, charged (n) hydrophillic, high energy bond, ion-ion and h-bonding

What is a carbonyl group, properties, and example?

could be aldehyde (glucose )or ketone (acetone/fructose) it is polar hydrophillic, reactive, dipole dipole