Biomolecules = macromolecules = large biological molecules necessary for life

Monomers = a building block to form something larger (lego block)

Polymers = something larger formed by monomers (lego castle)

4 Classes/Types of Biomolecules:

• Carbohydrates

• Lipids

• Proteins

• Nucleic Acids

CARBOHYDRATES:

Main function for organisms: Quick Energy Source

monomer = monosaccharide, dimer = disaccharide, polymer = polysaccharide

saccharide = sugar —> mono = 1 sugar, di = 2 sugars, poly = many sugars

POLAR molecules = HYDROPHILIC

identifying carbohydrate clues: most end in -OSE

Key Construction of Carbohydrates

Key Ideas for Polysaccharides

LIPIDS

Main function for organisms: cell membranes, long-term E storage, insulation, hormones

• generally don’t dissolve in water (HYDROPHOBIC) because they are overall NONPOLAR

made up of C, H, O

monomers = glycerol and fatty acids, polymers = triglycerides and phospholipids

• triglyceride = 1 glycerol, 3 fatty acids

• phospholipid = 1 glycerol, 2 fatty acids, 1 phosphate group

saturated fatty acids: chain of C, H, O with single bonds between C (straight)

• solid at room temp because they can stack together densely

unsaturated fatty acids: chain of C, H, O with 1+ double bonds between C atoms (bent)

• liquid at room temp because they can’t pack tightly together due to bends

trans fat: unsaturated fatty acid BUT the double bond is diagonal instead of straight

• are bent but not AS bent as unsaturated fatty acids so they can still pack tightly together by layering

NUCLEIC ACID

2 types of Nucleic Acids:

• DNA (deoxyribonucleic acid)

• RNA (ribonucleic acid)

DNA and RNA contain instructions for growth, reproduction, and heredity, helps build proteins

Made up of C, H, O, N, P

Structure of Nucleic Acids:

• monomers = NUCLEOTIDES

• nucleotides contain 3 compounds

  • phosphate group

  • pentose sugar (5 carbon sugar)

    • called RIBOSE in RNA

    • called deoxyribose in DNA (contains one less O than in RNA)

  • nitrogenous base

ATP = an energy storing nucleotide

(Adenosine Triphosphate, Adenosine Diphosphate)

• ATP is made up of 3 phosphate groups, adenine (nitrogenous base), and ribose sugar

• any cellular reaction that requires energy will use ATP

• ATP releases one phosphate to make ADP + P

• ADP + P will later return to the mitochondrion and a glucose molecule will be used to reattach the phosphate and make ATP again

Nitrogenous Bases in DNA nucleotide - ATCG

• Adenine

• Thymine

• Cytosine

• Guanine

Nitrogenous Bases in RNA nucleotide - AUCG

• Adenine

• Uracil

• Cytosine

• Guanine

how they combine:

• phosphate group in one nucleotide bonds with a pentose sugar in another

• makes a nucleic acid polymer

RNA:

• single-stranded nucleic acid

• travels from the nucleus to other parts of the cells to help assemble proteins

DNA:

• double-stranded nucleic acid

• linked together by hydrogen bonds between nitrogenous bases

• remains in the nucleus to store instructions to make proteins

Proteins

made up of C, H, O, N

structure of proteins:

• monomer = amino acids

• amino acids include

  • amino group

  • carboxyl group

  • unique side chain called R group

  • 20 possible R groups so 20 possible amino acids

• bonds that connect aa are called PEPTIDE BONDS

• protein polymers = peptides (shorter strands) and polypeptides (long strands)

Denaturing Proteins:

• heat or chemicals changing a protein shape → change / lose functionality

• usually NOT reversible, think of egg white turning white and solid, cannot change it back to its clear liquid form

Folded Shapes:

shape and function go hand in hand

different levels of structure:

• primary structure

  • sequence of aa that make up proteins

  • held by peptide bonds

  • protein synthesis = aa added to form a polypeptide chains

• secondary structure

  • can fold in two ways through hydrogen bonds between carboxyl and amines of two amino acids

    • Alpha Helix - COIL

    • Beta Pleated Sheet - ZIGZAG

• tertiary structure

  • glob like structure held by R-group interactions

  • hydrophobic groups will cluster in the middle

  • oppositely charged groups attract and hold together through H bonds or ionic bonds

  • same charged groups = repel

• quaternary structure

  • proteins made up of more than one polypeptide chain

Enzymes

• most enzymes are Proteins!

• enzyme ID hint: end in -ASE

• think of enzymes like PAC MAN

  • pacman’s mouth is like the ACTIVE SITE, where items can bind

    • substrates combine in the active site, fits like a puzzle piece

• Enzyme function:

  • ability to speed up reactions (catalyst), can be used over and over again

  • breaks down polymers into monomers so they can be digested easily

  • LIPASE - breaks down lipids

  • AMYLASE - breaks down starch

  • PROTEASE - breaks down proteins

Digestive System

4 major tasks:

• ingestion

  • intake of food

• digestion

  • breaking down biomolecule polymers into monomers

• absorption

  • absorption of water and nutrients, eventually delivered to cells

• elimination

  • waste removed from body

Mechanical Digestion: breaking down polymers into monomers physically, through eating, chewing, food turning in the stomach, etc.

Chemical Digestion: breaking down polymers into monomers chemically, through enzymes and other chemicals

• done by saliva, produced by salivary glands in the mouth

• 99% water, but contains salivary amylase = an enzyme that breaks down carbs

• Food turned into a little ball called a BOLUS

• Bolus is then swallowed, and enters the esophagus

• epiglottis blocks the windpipe/trachea from getting food into it

• peristalsis = muscular contractions that happen in the esophagus to help move the food down the esophagus

Stomach

• sphincter = separates the esophagus from stomach, and also stomach to small intestine

• very acidic, includes HCl and Pepsin = enzyme that breaks down proteins, chemical digestion

• produces LIPASE, PEPSIN, AMYLASE

• churning of stomach = mechanical digestion

• chyme = food particles and gastric fluid

Small Intestine - ABSORBS NUTRIENTS

• Duodenum Jejunum Ileum

• chemical digestion of all four biomolecules

• enzymes involved, digestive juices from PANCREAS

• 90% of all nutrients are absorbed here

• super long - 7m in length, HUGE surface area

Large Intestine / Colon - ABSORBS H2O

• feces remain at the end of the large intestine - the rectum, until it exits from the anus

Accessory Organs

• Gallbladder, Pancreas, Liver

• Liver = largest internal organ

  • produces bile = to break down lipids

  • stores glucose, makes protein

• Gallbladder = stores Bile, releases to duodenum when needed

• Pancreas = produces pancreatic juices that have important digestive enzymes that neutralize acid chyme

  • produces LIPASE, PROTEASE, AMYLASE, SODIUM BICARBONATE