Jimin's notes (Pt. 2)

Matter

Occupies space and has mass.

Elements

Substances that cannot be broken down or transformed chemically into other substances.

Atom

Smallest component of an element that retains all of the chemical properties of that element.

Proton

Positively charged particle that resides in the nucleus of an atom and has a mass of 1 and a charge of +1.

Electron

Negatively chatged particle that travels in the space around the nucleus; negligible mass and has a mass of -1.

Nucleus

Core of the atom.

Neutrons

Reside in the nucleus of the atom; mass of 1 with no charge.

Atomic Number

Equal to the number of protons that element contains.

Mass Number aka Atomic Mass

Number of protons + Number of neutrons of that element.

Periodic Table of Elements

The chart of elements that includes the atomic number and relative atomic mass of each element.

Isotopes

Different forms of the same element that have the same number of protons, but a different number of neutrons.

Radioactive Isotopes

Unstable, lose protons; other subatomic particles, or energy to form more stable elements.

Chemical Bonds

Interactions between two or more of the same or different elements that result in the formation of molecules.

Octet Rule

States that the outermost shell of an element with a low atomic number can hold eight electrons.

Ion

Number of electrons does not equal the number of protons, each ion has a net charge.

Cation

Positive ions formed by losing electrons.

Anion

Negative ions formed by gaining electrons.

Electron Transfer

Movement of electrons from one element to another.

Ionic Bond

Bond between ions; strong interaction and takes a larger energy input to break apart.

Covalent Bond

Bond between two or more atoms, when an electron is shared between two elements and are the strongest and most common form in living organisms; Do not dissociate in water. Ex. H2O.

Non-polar Covalent Bond

Forms between two atoms if the same element or between different elements that share electrons equally; Think: Electronegativity.

Polar Covalent Bond

Electrons shared by the atoms spend more time closer to one nucleus than to the other nucleus; slightly positive/negative charges.

Hydrogen-Bond

A weak bond between partially charged hydrogen atoms and partially negatively charged elements or molecules.

Van Der Waals Interactions

Weak attractions or interactions between molecules caused by slightly positive changed or slightly charged negatively charged ions.

Hydrophilic

Describes a substance that dissolves in water; water-loving.

Hydrophobic

Describes a substance that does not dissolve in water; water-hating.

Temperature

Measure of the motion (kinetic energy) of molecules.

Evaporation

Release of individual water molecules at the surface of the liquid.

Solvent

Substance capable of dissolving another substance.

Cohesion

The intermolecular forces between water molecules caused by the polar nature of water; creates surface tension.

Surface Tension

The cohesive force at the surface of a body of liquid that prevents the molecules from separating.

Adhesion

The attraction between water molecules and other molecules.

Litmus Paper

Filter paper that has been treated with a natural water-soluble dye so it can be used as a pH indicator; measures amount of hydrogen ions.

pH Scale

A scale ranging from 0 to 14 that measures the approximate concentration of hydrogen ions of a substance.

More hydrogen ions:

The lower the pH.

Fewer hydrogen ions:

Higher pH.

Pure water is:

Neither acidic or basic; pH of 7.0.

Basic pH:

pH = 7.1-14

Acids

Substances that provide hydrogen ions (H+) and lower pH.

Bases

Substances that provide hydroxide ions (OH-) and raise pH.

Buffers

A solution that resists a change in pH by absorbing or releasing hydrogen or hydroxide ions.

Acidic pH:

pH = 0.0-6.9

Macromolecules

A large molecule, often formed by polymerization of smaller monomers.

4 Major Macromolecules:

Carbohydrates, lipids, proteins, and nucleic acids.

Carbohydrate

A biological macromolecule in which the ratio of carbon to hydrogen to oxygen is 1:2:1; carbohydrates serve as energy sources and structural support in cells.

How do carbohydrates provide energy?

Though glucose, a simple sugar.

Monosaccharides

Simple sugars; 3-6 carbon atoms; -ose, trioses, pentoses, hexoses; In linear and ring-shaped molecules.

Disaccharides

Two sugar monomers that are linked together by a glycodsidic bond; undergo dehydration reaction.

Polysaccharide

A long chain of monosaccharides; may be branched or unbranched.

Starch

Stored form of sugars in plants and is made up if amylose amylopectin (both polymers of glucose).

Glycogen

Storage form of glucose in humans and other vertebrates, and is made up of monomers of glucose; usually stored in liver and muscle cells.

Cellulose

One of the most abundant natural bipolymers; provides structural support in plant cells; made up of glucose monomers that are linked by bonds between particular carbon atoms in the glucose molecule; broken down as dietary fiber in digestive system.

Lipids

A class of macromolecules that are nonpolar and insoluble in water. Cells store energy for long-term use as fats; provide insulation for plants and animals; building blocks for many hormones and important for plasma membrane; Fats, oils, waxes, phospholipids, and steroids.

Fat

A lipid molecule composed of three fatty acids and a glycerol (triglyceride) that typically exists in a solid form at room temperature.

Saturated Fatty Acids

A long-chain of hydrocarbon with single covalent bonds in the carbon chain; the number of hydrogen atoms attached to the carbon skeleton is maximized.

Unsaturated Fatty Acids

A long-chain hydrocarbon that has one of more than one double bonds in the hydrocarbon chain.

Oil

An unsaturated fat that is a liquid at room temperature.

Phospholipid

A major constituent of the membranes of cells; composed of two fatty acids and a phosphate group attached to the glycerol background.

Cells are surrounded by a membrane, which has a bilayer of _____.

Phospholipids.

Sterioid

Type of lipid composed of four fused hydrocarbon rings.

Protein

A biological macromolecule composed of one or more chains of amino acids. Strictural, regulatory, contractile, or protective; may serve in transport, storage, or membranes; may be toxins or enzymes. Polymers of amino acids, arranged in linear sequence.

Enzymes

Produced by living cells, catalysts in biochemical reactions, and are usually proteins; Specific for its substrate. Break molecular bonds, rearrange bonds, form new bonds.

Hormones

Chemicql signaling molecules, usually proteins or steroids, secreted gy an endocrine gland or group of endocrine cells thay act to control or regulate specific physiological processes, including growth, development, metabolism, and reproduction.

All proteins are made up of different arrangements of the same ____ amino acids.

20.

Amino acids

Monomers that make up proteins.

Fundamental amino acid structure

Central carbon atom bonded to amino group, a carboxyl group, and a hydrogen atom.

What makes the amino acids different?

The R group (determines the chemical nature of the amino acid within its protein).

Primary protein structure:

Sequence of a chain of amino acids; pattern based on genes, R-groups.

Secondary protein structure.

Hydrogren bonding of the peptide backbone causes the amino acids to fold into a repeating pattern. Simple folding due to H-bonds.

Tertiary protein structure.

3D folding pattern of a protein due to side chain interactions; origami due to R-group.

Quaternary protein structure

Protein consisting if more than one amino acid chain.

Nucleic acids

A biological macromolecule that carries the genetic information of a cell and carries instructions for the functioning of the cell.

Types of nucleic acid:

DNA & RNA

RNA

Mostly involved in protein synthesis and regulation, helps DNA communicate with the rest of cell.

DNA and RNA are made up of monomers called:

Nucleotides = nitrogenpus base, a pentose (5-carbon) sugar, and a phosphate group.