Biochemistry Flashcards
Proton (Charge, Mass and Location)
+, 1, nucleus
What does an atom consist of
Subatomic particles: protons, neurons and electrons
Neuron (Charge, Mass and Location)
Neutral, 1, nucleus
Electron (Charge, Mass and Location)
-, 0, outside nucleus
What charge is an atom in the elemental state?
Neutral because the number of protons equals the number of electrons
Why is Electron Configuration important?
It determines how a particular atom will react with atoms of other elements
Ground state
The electrons are in the lowest available energy level
Excited State
The state an atom reaches when it absorbs energy and the electrons move to a higher energy level
Isotopes
Atoms of an element that vary only in the number of neurons in the nucleus. Chemically identical.
Radioisotopes
Radioactive Isotopes
Emit particles and decay at a known rate: half-life
Used in medical diagnosis, treatment and research
Radioactive Iodine (I-131) used to diagnose and treat disease of the thyroid
Half-life
When the nuclei or radioisotopes emit particles and decay at a known rate. Help determine age of fossils/Earth. Also used for medical diagnosis, treatment and research. Radioactive carbon can be used as a tracer in carbon dioxide molecules to track metabolic pathways
How is a bond formed?
When two atomic nuclei attract the same electron(s). Energy is released when a bond is formed.
Ionic bonds
Bonds formed when electrons are transferred.
Anion
A Negatively charged ION, that gains electrons from an ionic bond.
Cation
A postively charged ion: An atom that loses an electron from an ionic bond
Covalent Bonds
Bonds formed when atoms share electrons. Two types: Nonpolar and Polar.
Single Covalent Bond
Two atoms share one pair of electrons
Double Covalent Bond
Two atoms share two pairs of electrons.
Nonpolar Covalent Bonds
Electrons are shared equally and the bond is formed between any two atoms that are alike
Polar Covalent Bond
Electrons shared unequally and the bond is formed between two atoms that are unalike
Tracer
Combined with another substance and used to track metabolic pathways. (Radioactive carbon can be used as a tracer combined with carbon dioxide)
Intermolecular Attractions
Attractions between molecules
Polar-Polar Attraction
Two polar (unbalanced) molecules that form a strong bond (because of polarity)
Hydrogen Bonding
A weak bond between hydrogen and other elements. Keeps DNA strands bonded. allows water molecules to stick together, responsible for many characteristics of water
Nonpolar Molecule Attraction
Balanced and weak
Hydrophobic
Water-hating, repelled by water
Usually nonpolar molecule
Hydrophilic
Water-liking, attracted to water
Polar Molecules
Opposite charges on opposite sides of the molecule, dissolves in water (hydrophilic), very strong bond between the molecules
Nonpolar Molecules
Same charge throughout the molecule, does not dissolve in water (hydrophobic), bonds between these molecules are weaker
Lipids
Nonpolar, hydrophobic, organic compounds: fats, oils, waxes. monomer: 3 fatty acids, one glycerol. Polymer: lipids. 9 cals/gram
Characteristics of Water
Asymmetry, polarity, strong intermolecular attractions (because of its polarity) and hydrogen bonding
1) Has a high specific heat
2) Uses high amounts of heat to evaporate
3) Is adhesive
4) Is a universal solvent
5) Exhibits cohesion tension
6) Is denser than ice
Specific Heat
The amount of heat needed to be absorbed in order for 1 gram of a substance to change its temperature by 1 degree celcius
Adhesion
The clinging of one substance to another
Cohesion
The clinging of one substance to itself (polarity)
Transpirational-Pull Cohesion Tension
The phenomena where water can move up a tall tree (from roots to leaves) without using energy
pH
A measure of acidity or alkalinity by amount of hydrogen ions in a solution
0-7 acidic many H ions, = 7 is neutral, 7-14 alkaline/base few H ions
slight change in pH can be harmful
the negative log of the concentration of hydrogen ions in moles per liter
Organic Compounds
Compounds that contrain carbon
There are four classes: Carbs, lipids, proteins and nucleic acids
Buffers
Substances that resist change in pH, regulate pH levels in biological systems by absorbing or donating hydrogen ions (ex: bicarbonate ion (HCO3-) the buffer in the human blood)
Monosaccharides
Chemical Formula: C6H12O6
Monomer of Carbs
ex: Galactose, Fructose, Glucose (picture)
Carbohydrates
Made of carbon, hydrogen and oyxgen
Supply quick energy (gives energy to the brain)
4 cals/1 gram burned
Three classes: monosaccharides, disaccharides and polysaccharides
Monomer: monosaccharides
Polymer: polysaccharides
Disaccharides
Chemical Formula: C12H22O11
two monosaccharides joined by dehydration synthesis
ex: Lactose, Sucrose, Maltose (picture)
Isomers
Compounds with the same molecular formular, but different strutures, so they have different physical and chemical properties
Hydrolysis
The process where a compound is broken down with the help of water (It occurs during digestion)
C12H22O11 + H2O –> C6H12O6 + C6H12O6
Dehydration Synthesis
The process where molecules join together and release water as a by-product
C6H12O6 + C6H12O6 –> C12H22O11 + H2O
Cellulose
Found in plants, makes up plant cell wall
Polysaccharides
The polymer of carbs, four important ones: cellulose, starch, chition, glycogen
Chitin
Found in animals, makes up the xoskeleton of arthropods and the cell walls of mushrooms
Starch
Found in plants, storage house for carbs in plants
Glycerol
Alcohol, monomer of lipids
Glycogen
Found in animals, storage house for carbs in animals, stored in the liver and skeletal muscles in humans
Saturated Fats
Generally come from animals, solid at room temperature (linked to heart disease), a single bond between the carbon atoms
Fatty acid
Hydrocarbon chain with a caboxyl group at one end. comes in two types: saturated and unsaturated
Proteins
Complex macromolecules and responsible for growth and repair
4 cals/gram burned
Monomer: amino acids, polymer: polypeptides
Held together by peptide bonds
Elements: S - Sulfur, P - Phosphorus, C - Carbon, O - Oxygen, H - Hydrogen and N - Nitrogen
Amino Acids
The monomer of proteins. Consists of a carboxyl group, amine group and a variable (R) group attached to a central carbon atom. The R group makes a protein unique (each protein has a different R group)
Unsaturated Fats
Come from plants, liquid at room temperature, double bond between the carbon atoms
Lipid Functions
1) Energy storage
2) Structural (cell membrane)
3) Endocrine (hormones)
Primary Protein Structure
This structure results from the unique sequence of amino acids that make the protein chain
Secondary Protein Structure
This structure results from the hydrogen bonding within the molecule (because of the helical nature of proteins)
Dipeptide
A molecule consisting of 2 amino acids connected by a peptide bond
Protein Structure
The function of a protein depends on the shape of the protein. The shape is determined by 4 levels of structure: primary, secondary, tertiary and quaternary
Enzymes
Large proteins that speed up chemical reations by lowering the enrgy of activation Ea.
Named after the substrate with the suffix “-ase”
Assisted by cofators (minerals) and coenzymes (vitamins)
Properties: Specificity, reusability, sensitivity to pH and temperature (has a range of pH and temperature that it works optimally at)
Has an active site where the substrate goes
Energy of Activation
The amount of energy needed to begin a chemical reaction
Tertiary Protein Structure
The 3D shape/conformation of the protein. This structure directly determines the function of the protein.
Quaternary Protein Structure
The structure of proteins with more than one polypeptide chain
Active site
The part of an enzyme the substrate attachs to
Cofactors
Minerals that aid enzymes
Substrate
The chemical an enzyme works on
Induced-fit Model
A model to describe how enzymes work: the substrate enters the active site causing the enzyme to change slightly in order to allow the substrate to fit better
Nucleotides
Monomer of nucleic acids. Consist of a phosphate, 5-carbon sugar (deoxyribose or ribose) and a nitrogenous base
Nucleic Acids
DNA & RNA, carry hereditary info, the polymer of nucleotides
Prions
Infectious, misfolded proteins that cause brain diseases by infecting the other proteins in the brain and cause them to misfold also
Coenzymes
Vitamins that aid enzymes
Purines
Adenine and guanine
RNA
Sugar: Ribose. Nitrogenous Bases: adenine, cytosine, guanine and uracil
DNA
Sugar: Deoxyribose. Nitrogenous Bases: adenine, cytosine, guanine and thymine
Nitrogenous Bases
Nitrogen containing base in nucleotides. Bases that help determine the amino acids formed. Two bases bond through hydrogen bonding
Pyrimidines
Cytosine, thymine and uracil
Polymer
A large molecule of similar units attached in a series, forming a chain
Denaturation
The process in which a protein’s conformational shape changes causing the protein to lose its function(usually by temperature or pH)
Macromolecule
A single, large molecule formed by many smaller organic molecules (ex: lipids, proteins, nucleic acids, carbs)
Isomer
Molecules made with the same atoms but have different structures.
Van der Waals
The weakest attraction between nonpolar molecules (nonpolar covalent bonds)
Fructose
A monosaccahride.
C6H12O6
[Add picture]
Glucose
A monosaccahride used as raw material for cellular respiration
C6H12O6
[Add picture]
Monomer
A single unit of stuff that makes up a polymer of that stuff
Peptide Bond
The bond formed by dehydration synthesis between amino acids
Ion
An atom or molecule that has lost or gained an electron (so it has a chrage either positive or negative)
Acid
pH value of < 7 and rich in H ions
Donate H ions to solutions
They are highly reactive
Base
pH of > 7 and has few H ions
Removes H ions from solutions
Bond Energy
The amount of energy needed to break a bond. It’s requal to the amount of energy needed to form the bond
