UNIT 1 : PART 1 : BIOLOGY REVIEW Flashcards
What is an Isotope
When two atoms share the same number of electrons and protons but a different amount of neutrons; thus their atomic mass differs.
Example: Carbon 12, 13, 14
What is a Isomer
Compounds in which have the same Molecular formula but differ in chemical arrangement.
→ Glucose, Galactose, Fructose
Radioisotopes
Unstable Isotopes whose nuclei spontaneously break apart and are used in
→ Radioactive Dating
→ Radioactive Tracing
Forces of Attraction
The bonds that hold atoms of a molecule together or ions of an ionic solid together.
Ionic Bond
The attraction between positive and negative charges. It’s where one atom electron is strongly attracted to another atom electron.
(Interchanging - + and - charges)
Covalent Bond
When two atoms share one or more pairs of electrons, and the sharing of electrons can either be equal or unequal. If it is equal there is non polar bonding, if it is unequal then there is polar bonding
Electronegativity
The measure of how strongly an atom is able to attract electrons within a bond,
→ Good indicator for polarity
→ As well as showcases whether within a covalent bond, sharing is equal or unequal
The Dehydration Reaction
When two subunits link together through the removal of a water molecule
→ Anabolic Reaction: Absorbs energy
The Hydrolysis Reaction:
When two subunits break apart from the addition of a water molecule
→ Catabolic Reaction: Releases Energy
Neutralization
→ When an Acid and a Base Mix
→ The H+ ions combine with the OH ions → to form water
→ Always yields a water and a salt
Redox Reactions
→ Oxidation : Loss of electrons
→ Reduction : Gaining electrons
→ Happen together or at the same time
→ The substance that is oxidized is the reducing agent
→ The reduced substance is known as the oxidizing agent
Hydrogen Bonding
: When a Hydrogen ion attaches to a EN ion that has unshared electron pairs
(dipole-dipole reaction)
Properties due to H-Bonding : 5 Properties of Hydrogen Bonding
Universal solvent : Most polar and all Ionic compounds → Transport of nutrients, proteins, sugars and hormones
Cohesion: H atoms bond together forming a membrane bound structure →
High Heat Capacity: High heat capacity; where it will not change form for an extended period → Important in maintaining body temperature
Capillary Action : Will adhere to small tube like structures against gravity → Blood moving through veins or, water moving from the roots of a plant upwards
The ability to change shape: When water cools, it forms a crystalized structure in which takes up more space than when in its liquid form
Buffers
→ Resist changes in pH despite when an acid or base is added
→ Can either act as an acid or as a base
→ Composed of a conjugate base and a weak acid
Organic chemistry
The study of carbon compounds → Hydrocarbons
Carbohydrates
→ The main source of short term energy
→ Building Material → Exoskeleton
→ Cell surface recognition molecules
Carbohydrate Formula
Formula be (CH2O)n
→ N is variable but for example in glucose the formula is (CH2O)6
Monosaccharides
Mono means 1, Saccharide means Sugar → Single Sugar or Simple Sugar
→ Functional groups are Carboxyl and Hydroxyl
A glucose - B glucose
In the dry and linear form there is no difference between A and B glucose
However in water the OH at C5 reacts with the aldehyde at C1 to form a ring
A Glucose → When the OH is BELOW the C at C1
B Glucose → When the OH is ABOVE the C at C1
50 percent chance of either occurring
Stereoisomers
: Have the same chemical formula and even shape, but they differ in three dimensional orientations
Oligosaccharides:
→ 2-3 Monosaccharides (2 is usually called di-sachraides)
→ Formed through Glycosidic linkages
→ Dehydration Synthesis
Disaccharides
→ Sucrose : Glucose + Fructose
→ Maltose : Glucose + Glucose
→ Lactose : Glucose + Galactose
Polysaccharides
Long chains of hundreds to thousands of monosaccharides (glucose) from glycosyl bonds
→ Straight ot Branches
2 TYPES of Carbohydrates
Storage : Starch & Glycogen
Structural Chitin, Cellulose
Starch: Is made up of
Amylase : A glucose → Straight
Amylopectin : A glucose → Branched
Starch Hydrolysis :
The breakdown of starch through the hydrolysis of glycosidic bonds, forming maltose
→ Through the digestive enzyme known as amylase
Cellulose :
→ Most abundant form of biological compound
→ Straight Chained
→ B Glucose
→ Requires special digestive enzymes
Glycogen
→ principal store molecule for plants and animals
→ stores energy when it is needed, replenished daily
→ Very Highly Branched
Chitin
→ Second most abundant molecule
→ Contains N groups
→ Found in the exoskeleton of crustaceans as well as in contact lenses and stitches
Lipids
→ More calories than carbohydrates
→ Acts a insulation
→ Main component in cell membranes
→ Used as chemical messengers
→ Hydrophobic → Repels Water
→ Contains Oxygen Hydrogen and Carbon
→ Soluble only in acetate, alcohol, ether, and chloroform
Fatty Acids
2 - 24 carbon atoms
Carboxyl group on one end, methyl group on the other
Saturated Fatty Acid :
Carbon atoms saturated with Hydrogen Bonds
→ Firm and Solid → Animal Fats
→ Difficult to break down
Unsaturated Fatty Acid:
→ Carbon atoms contain double bonds where they could contain more hydrogen atoms
→ Liquid Plant Fats : Vegetable Oils → Easily broken down because Double Bonds react easier
→ Hydrogenation →Adding H+ Ions to make Fat firmer, like in peanut butter
Triglyceride
→ Most common type of lipid
→ 1 glycerol; 3 fatty acids
→ Esters are formed
Phospholipids
→ 2 fatty acids, and one glycerol molecule attached to a phosphate group
→ Hydrophobic tail, Hydrophilic Head
→ Amphiphatic
Carotenoids
→ Special Photosynthetic Pigments that are needed in addition to chlorophyll
Carotenoids
→ Special Photosynthetic Pigments that are needed in addition to chlorophyll
Waxes
→ Highly Suitable waterproof coating
Steroids
→ Have 4 rings
→ Variations in Functional Groups and Double Bonds
Cholesterol
→ Used to make certain hormones (testosterone, and estrogen)
→ Very important for nervous system function and important for cell membranes
Proteins
→ Diverse macromolecules
→ Made up of chains of amino acids
→ 20 amino acids are needed
→ 12 are naturally synthesized, 8 must be consumed within the diet
Proteins
→ Diverse macromolecules
→ Made up of chains of amino acids
→ 20 amino acids are needed
→ 12 are naturally synthesized, 8 must be consumed within the diet
Amino Acid Structure
→ Central carbon attached to a Hydrogen, Carboxyl Group, Amine Group, R group
Peptides
→ 2 or more amino acids, named after how many they have
2 - dipeptides 3-tripeptides 10-15 oligopeptides 100+ proteins
Protein Structure
- Primary: amino acid sequence determines this
- Secondary: deals with hydrogen bonding between amino acids → alpha helix or beta pleated sheet
- Tertiary: helices and beta sheets fold upon themselves → Makes the supercoiling 3D structures
- Quaternary: Two or more polypeptide chains interacting with each other
Insulin
→ Two polypeptide chains formed by a disulfide bridge
Polypeptides
→ Amino acids that connect in sequences to form polymers called polypeptides
Nucleic Acids
→ Found in DNA, RNA, and ATP, Nucleotide Coenzymes → Used in Energy Transformations
→ DNA & RNA : Nucleotide Polymers
Nitrogenous Bases → A,G,T,C
One spine of the ladder combine with NB from the other side of the ladder through hydrogen bonds
DNA : Individual units of deoxyribose sugars, phosphates, and nitrogenous bases
Protein Denaturation:
Protein Denaturation:
→ Overall 3D shape is critical for function : Proteins can change shape
Denaturation : Drastic Changes to a protein’s conformation which can cause it to lose function or destroy it completely
→ pH or heat
→ Often is “Permanent”
DNA VS RNA
Different Sugars : Deoxyribose Sugars
→ DNA : Double Stranded, RNA: Single Stranded
→ DNA: Thymine RNA: Uracil
– Found in nucleus, nucleus and cytoplasm
–. Dna code of life, rna makes proteins using dna
ATP
→ Adenosine triphosphate
→ Monomer
→ Energy Storage Molecule
→ High energy bonds between phosphate groups
