A&P Chapter 2 - Lecture notes 2 PDF

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Biol 2401 with Prof. Vasefi...

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Anatomy & Physiology Chapter 2 1 of 5

Chemical Elements: basic building blocks, can’t be broken down into smaller substances (/) made of 1 type of atom, 118 known elements- 92 naturally, 27 in human body

Particle

Charge

Mass

Location

proton

+

large

nucleus

neutron

none

large

nucleus

electron

-

small

orbits nucleus

3 #’s Describe Atoms: (/) atomic #-> # of protons (/) mass # -> # of protons + # of neutrons (/) atomic mass-> average mass of naturally occurring isotopes, measured in daltons or AMUS to calculate, multiply each isotope mass by abundance then add them all together

Isotopes: atoms of same element w/t diff. # of neutrons (/) most have same # of neutrons as protons Ions: atoms w/t charge, have gained/lost electron (/) Cation- lost electron, became pos. (/) Anion- gained electron, became neg.

Compound: substance composed of 2 or more types of molecules (elements) (/) symbolized by molecular formula which show elements involved & # of atoms

Electrons orbit nucleus in specific regions called shells: (/) First shell holds 2, 2nd shell holds 2, third holds 8 (/) To be stable, wants to fill last shell (valence) octet rule: fill last valence shell to 8 to be stable, so attract atoms

Hydrogen: exception to octet rule (Helium too) b/c only 1 valence shell (only 2 e needed) 3 Types of Chemical Bonds: (/) covalent- two atoms share 1/2/3 pairs of electrons increased bond strength ->non-polar: 2 atoms share electrons equally ->polar: 1 atom (electronegative) attracts electron more than other, unequal sharing (/)ionic- forms when 1 atom takes the electron from another

Anatomy & Physiology Chapter 2 2 of 5 NaCl for instance, often crystalline, mineral salts that form bones & teeth (/) hydrogen- formed when hydrogen atom w/t p+ charge attracts atom w/t n-charge depends on attraction b/t polar molecules not on sharing electrons weaker than ionic/covalent link distant parts of molecule

Chemical Reactions: interactions b/t atoms forming/breaking chemical bonds b/t atoms (/) involves reactants, products, work & energy

Reactants: starting substances of chemical reactions Products: ending substances of chemical reaction Law of Conservation of Mass: matter cannot be created/destroyed Work: movement of object or change in physical structure of matter Energy: capacity to do work Kinetic Energy: energy of matter in motion Potential Energy: stored energy derived from objects’ position or chemical/physical state Chemical Energy: energy stored in chemical bonds, form of PE (batteries) Endergonic Reaction: absorb more energy than release (/) associated w/t anabolism (forming chemical bonds)

Exergonic Reaction: release more energy than absorb (/) associated w/t catabolism (breaking chemical bonds)

Activation Energy: energy required to initiate chemical reaction (/) amount depends on concentration of reactants & temp.

Catalysts: chemical compounds that speed up chemical reactions by lowering AE needed (/) not changed/consumed by chemical reactions, can catalyze many reactions

Reactions in body done through catalysts (enzymes) Inorganic Compounds: lack carbon, ionic/covalent bonds, simple structure ( /) Ex: H2O

Organic Compounds: always have carbon & covalent, usually hydrogen, complex structure (/) Ex: Glucose (C6H12O6)

H2O (Water): inorganic, has 4 properties (/) solvent- medium in which others are dissolved solution = fluid w/t dissolved substance

Anatomy & Physiology Chapter 2 3 of 5 solute = dissolved substance (/) lubricant- reduces friction b/t 2 surfaces found in various fluid-filled cavities (/) high heat capacity- can absorb & retain high heat w/t small change b/c of polar bonds requires lots of heat to change from liquid to gas when evaporates, removes lots of heat (sweat) (/) involved in metabolic reactions anabolic reactions make water byproducts when making complex molecules

Inorganic Acids: dissolves into H+ (anion) (/) proton donor

Inorganic Bases: dissolves into OH- (cation) (/) proton receiver

Inorganic Salts:

dissolves into anion & cation but not H+ &

OH- Acids & Bases react to form salts: HCL + KOH -> KCL + H20

PH: measures relative concentration of H+, ranges from 0-14 (/) PH < 7 : acid (/) PH = 7 : neutral (/) PH > 7 : basic

Organic Macromolecules: made of lots of small organic molecules (/) often take form of polymer (made of identical repeated monomers)

Major Categories of Organic Compounds: produced by living organisms (/) carbohydrates- contains C,H,O, includes sugars, glycogen, starches & cellulose used as source of chemical energy (/) lipids- has C,H,O. Insoluble in water (non-polar & hydrophobic), made of fatty acids fatty acids- most simple, made of hydrocarbon chain & carboxyl group (COOH) -> simple monomers that form polymers triglycerides- fairly simple polymers, made of 1 glycerol & 3 fatty acids -> at room temp, solid (fat) or liquid (oils) -> stored in fat tissue (adipose as energy reserve) phospholipids- 1 glycerol molecule, 2 fatty acids & 1 phosphate group -> amphipathic molecules (made of polar [hydrophilic] & non-polar [hydrophobic]) -> cell membrane made of phospholipid bilayer

(/) proteins- wide variety of molecules, has C/H/O/N & sometimes sulfur more complex than carbs & lipids (structurally & functionally) includes enzymes (biological catalysts) protein structure- determines function

Anatomy & Physiology Chapter 2 4 of 5 Ex: enzyme structure allows it to bind to substrate ->primary- sequence of amino acids monomers in long lined structure ->secondary- twisting & folded, often alpha helix or flattened sheet ->tertiary- 3d shape, coiled & folded w/tin cylindrical segments in double helix ->quaternary- made w/t 2 or more polypeptide chains

(/) nucleic acids- has C, H, O, N & P, includes DNA & RNA complex polymer made of nucleotide monomers made of pentose sugars (deoxyribose or ribose), phosphate group & 1 nitrogenous base nucleotides of DNA-

ring

->purine- adenine & guanine, large w/t 2 nitrogen containing rings ->pyrimidine- cytosine & thymine (uracil in RNA), small w/t 1 N containing DNA Structure- AT/CG double helix ->upright parts of ladder: made of pentose sugar & phosphate group ->rungs made of nitrogenous base pairs linked by hydrogen bonds

RNA- single strand, ribose not deoxyribose, uracil not thymine, 3 types ->mRNA- messenger RNA, decides where amino acids go, opp. copy of DNA ->tRNA- transfer RNA, binds w/t amino acid & transports it to protein synthesis sit ->rRNA- ribosomal RNA, attaches to mRNA & matches its codons w/t tRNA

Monosaccharides: monomers of carbs (glucose & fructose) (/) 2 monosaccharides -> disaccharide sucrose (table sugar)

Polysaccharides: made of many monosaccharides, 3 important groups (human physiology) (/) glycogen- branched molecule, stored in liver & skeletal muscles as energy reserve (/) starches- produced by plants, used for energy storage by plants digestible by humans (potatoes), unbranched polymer (/) cellulose- produced by plants, used to build cells walls by plants, not digestible by humans

Amino Acids: building blocks of proteins, 20 different kinds (/) composed of amino group (NH2), carboxyl (COOH), side chain (diff. in each amino acids)

Polypeptides: amino acids joined together w/t peptide bond Peptide Bonds: covalent bond b/t carbon of COOH & amino acid & nitrogen atom of other amino acid Structural Relationship: how polypeptide chains wrap around each other Hemoglobin made of 4 globules, keratin & collagen -> 3 Denaturation: process when proteins lose 3D shape in PH or temp. extremes (/) interrupts proper functioning of protein

Anatomy & Physiology Chapter 2 5 of 5

Review of Bio Macromolecules

DNA

RNA

gene repositor y stays in nucleus double strand thymine bond w/t adenine

Monomer

brings genes to cellular machine ry can leave nucleus

monosaccharid e fatty acid

single strand

nucleotide

Complex Organic Molecule carbohydrat e lipi d

amino acid

protein nucleic acid

uracil bond w/t adenine

Adenosine Triphosphate (ATP): energy currency of cells (/) made of adenine & ribose sugar & 3 phosphate groups (/) links exergonic catabolism & endergonic catabolism (/) stores chemical energy in bonds

If phosphate group is removed from ATP, becomes ADP & released energy. (ADP- adenosine diphosphate) Adding phosphate group back produces ATP & uses energy. ADP + P + energy = ATP + H20...