Anatomy & Physiology Ch 1 & 2
Anatomy: Study of form
Physiology: Study of function
Study of Form
Examining Structure of the human Body:
1. Inspection: looking at the body’s appearance as we perform an exam. Looking for a change in appearance.
2. Palpation: Feeling with hands. Example: feeling swollen lymph nodes or taking a pulse rate at the wrist.
3. Auscultation: Listening to the sounds made by the body listening for abnormalities. Ex: Heart, lungs.
4. Percussion: tap on the body and feel abnormal resistance. Ex: pockets of air, scar tissue, pockets of fluid.
5. Dissection: Cutting apart and separating tissue to see how they relate to another. Ex: Cadaver dissection.
6. Comparative anatomy: examine multi species to see trends from evolution.
7. Medical imaging: view inside the body without surgery. EX: xrays, MRI, CTs, other scans. Radiology is the branch of medicine concerned with imaging.
8. Gross Anatomy: study of structures that can be seen with the naked eye. (without microscopes)
9. Histology: viewing structures microscopically utilizing slides and microscopes.
10. Histopathology: Examining microscopic cells or tissues in the hunt for disease.
11. Cytology: Study and structure of individual cells and their functions.
12. Ultrastructure: viewing the inner structures of a cell and high magnification electron microscope.
Physiology – The study of Function
Subdisciplines:
1. Neurophysiology- physiology of the nervous system
2. Endocrinology- physiology of hormones
3. Pathology- Mechanisms of disease
Comparative Physiology: Study of different species to learn about body functions. Basis for much of the understanding of human physiology and the development of new drugs and medical procedures.
·How different species have solved the problems of life. Ex: water balance, respiration, reproduction.
1.2 Origins of Biomedical Science
Modern biomedical science emerged from an era of superstition and authoritarianism.
Ex: using physical therapy, herbs, salts, faith healing. (3,000 years ago)
Hippocrates & Code of Ethics
· Greek Physician; “Father of Medicine,”
· Established code of ethic: The Hippocratic Oath.
· Urged physicians to seek natural causes of disease rather than attributing them to activities of gods or demons. Rational basis for therapy. Natural progression of disease process.
Aristotle “Parts of the Animals,”
First to write anything about anatomy and physiology but also tried to identify themes in nature.
· Believed diseases had supernatural or physical causes.
o Theologi: supernatural causes of disease.
o Physiologi: natural causes for disease.
o Gave rise to the terms: Physician & Physiology.
· Believed complex structures were built from simpler parts. How body systems work together.
Claudius Galen “Gladiators,”
Physician to Roman Gladiators. Comparative anatomy with animals.
Did animal dissections because use of cadavers was banned due to previous dissection abuse.
Saw science as a method of discovery, trust in the individual’s observation and acknowledged his own fallibility.
Teachings were adopted as dogma in Europe in Middle Ages but was not accepted during his time.
Maimonides
A Jewish physician and rabbi who served in the court of Saladin and wrote many books on medicine and disease.
William Harvey 1500s “Motion of the Heart,”
contributed to the study of physiology especially of the heart. Credited with beginning the field of experimental physiology.
Andreas Vesalius “Italian Autopsy,”
Italian who taught anatomy to medical students using cadavers in the 1500s.
Avicenna
A Muslim scholar who wrote the book called “the Canon of Medicine.”
Birth of Modern Medicine
Robert Hooke – looking at the cellular level. Mid-1600s
First to see and name “cells.”
Made many improvements to compound 2 lens microscope: Magnified 30x only
Ocular lens (eye piece)
Objective lens (near specimen)
Invented specimen stage, illuminator, course and fine focus controls.
Observed shavings of a cork tree and observe “little cells,” named after cubicles in monasteries.
Noted that living cells were filled with fluid what we know now as cytoplasm.
Published first comprehensive book of microscope Micrographia in 1665.
Anthony van Leeuwenhoek – Textile Merchant
Invented a handheld, single lens microscope with great magnification to look at fabrics.
200x due to bead shaped lens created through his superior shaping techniques that enhanced focusing ability.
Published his observations of blood, lake water, sperm, bacteria from tooth scrapings and many other things. After examining lake water: “Animolicules,” “wee little beasties.”
Images under the scope are still poor with distortions and blurry. Building block to knowledge that there are small organisms that humans can’t see to the naked eye.
Matthias Schleiden (botanist) & Theodor Schwann (zoologist) 1893
Examined wide variety of specimens and concluded that “ all organisms were composed of cells.”
First tenet of Cell Theory:
Considered to be perhaps the most important breakthrough in biomedical history
All functions of the body are interpreted as effects of cellular activity.
The cell is the basic unit of life, and the first level of the structural hierarchy displays life processes.
Scientific Method
Francis Bacon (England) and Rene Descartes (France)
Philosophers who invented new, disciplined creative and objective habits of scientific thought. Felt science was as a greater systematic enterprise that had enormous possibilities for human health and welfare. Argued against bias thinking of current ideology and looked for objectivity in science.
Bacon: They sought systemic ways of seeking similarities, differences and trends in nature and drawing useful generalizations from observable facts. Inductive Method.
Put science on a modern pathway to discovery.
Science and Scientific Methods & Proof in Science
Set standards for truth and building foundations of research on facts
Bacon’s Inductive method: making numerous observations until one becomes confident in drawing generalizations and predictions.
Reliable observations, repeatedly confirmed, not falsified by any credible observation.
“Proof beyond a reasonable doubt.” In Science, all truth is tentative. “Until it has been refuted later on.” Conclusions are open to correction.
The Hypothetico- Deductive Method
Most physiological knowledge gained by this method investigator formulates a hypothesis an educated speculation or possible answer to the question. An educated guess.
Good hypotheses are consistent with what is already known and testable.
Falsifiability, if we claim something is scientifically true, we must be able to specify state what evidence it will take to prove it wrong. If it can’t be proved wrong, it isn’t science.
Deductive Method | Inductive Method |
I start with a theory | I start with data |
I confirm a hypothesis | I infer conclusions from my data |
I tend to do quantitative research. (numbers) | I tend to do qualitative research. (observation) |
Scientific Fact: Information that can be independently verified. Ex: Anemia is an iron deficiency.
Law of Nature: generalization about the predictable way matter and energy behave. Results from inductive reasoning and repeated observations. Written as verbal statements or mathematical formula. Ex: Law of complementary based pairing.
Theory: an explanatory statement or set of statements derived from facts, laws, and confirmed hypotheses. Summarizes what we know and suggests directions for further study.
1.5 Human Structure
Hierarchy of Complexity 1
Organism: composed of organ systems.
Organ systems: Composed of organs.
Organs: Composed of tissues. At least 2 different tissues with recognizable boundaries and with a discrete function.
Tissues: composed of cells
Cells: composed of organelles. Smallest unit of life.
Organelles: composed of molecules. Microscopic structure that carry out specific function.
Molecules: composed of atoms. Ex: Protein, lipids, ect.
Anatomical Variation
No two humans are exactly alike, even identical twins.
In groups individuals may lack certain muscles (pulmaris longus) , atypical number of vertebrae or organs like kidneys. Some individuals have situs inversus, left right reversal of organ placement (heart).
Characteristics of Life - A Collection
Organization: Living things exhibit a higher level of organization than nonliving things.
Cellular composition: Living matter is always compartmentalized into one or more cells.
Metabolism: internal chemical reactions
Responsiveness: ability to sense and react to stimuli (Irritability, excitability)
Movement: of organism and or substances within the organism
Homeostasis: Maintaining/ manage relatively stable internal conditions
Development: Differentiation and growth
Reproduction: producing copies of themselves; passing genes to offspring
Evolution: Changes in genes.
Physiological Variation
Typical physiological values and variations in: sex, age, diet, weight, physical activity, genetics and environment.
Example: 22 years old male, 154 lbs, light physical activity, consumes 2800 kal/day. Verses, 22 year-old female 126 lbs, light physical activity and 2000, kcals/day.
Can lead to mistakes like overdosing medication, ect
Homeostasis & Negative Feedback
Homeostasis: the ability to detect change, activate mechanisms that oppose it, and thereby maintain relatively stable internal conditions. Loss of homeostatic control causes illness or death.
Negative feedback: the body senses a change and negates or reverses it which allows for dynamic equilibrium within a limited range around a set point.
Feedback loop: mechanisms altering the original changes that trigger them.
Receptors: structures that senses change in the body (e.g., stretch receptors above the heart that monitor blood pressure)
Integrating (control) center: control center that processes the sensory information, “makes a decision,” and directs the response (cardiac center of the brain)
Effector: cell or organ that carries out the final corrective action to restore homeostasis (ex: heart)
Body Temperature Homeostasis (hypothalamus)
When too warm, vessels dilate in the skin and sweating begins as a heat losing mechanism.
When too cold vessels in the skin constrict and shivering begin, a heat gaining mechanism.
Positive Feedback & Rapid Change
Self-Amplifying cycle: leads to greater change in the same direction. Feedback loop is repeated, change produces more change.
Normal way of producing rapid changes
Ex: childbirth, blood clotting, protein digestion and generation of nerve signals.
Sometimes dangerous. Ex: vicious circle of runaway fever. Fevers are beneficial to a certain point; metabolic rate increases and can be dangerous and or fatal.
Gradient & Flow
Matter and Energy tend to flow down gradients. (Higher to lower concentrations is: Down gradient)
Gradient: a difference in chemical concentration, charge, temperature or pressure between two points.
Ex: blood flows from a place of higher pressure to a place of lower pressure.
Movement in the opposite direction is “up the gradient” and requires spending metabolic energy.
· Chemicals flow down concentration gradients.
· Charged particles flow down electric gradient.
· Heat flows down the thermal gradients.
1.7 Language of Medicine
Terminology based on word elements
Refer to the Lexicon of 400-word elements can be found on the inside back cover of textbook
Scientific Terms Systems
1. Root (system) with core meaning. Ex: Cardi
2. Combining vowels join roots into a word
3. Prefix and/or Suffix may modify meaning of root word. Ex: epi, hypo, endo
4. Acronyms: pronounceability words form from first letter, or first few letters of a series of words.
a. Ex: PET Scan (positron emissions tomography)
b. VS: DNA which is abbreviation
1.8 Review of Major Themes
Unity of form and Function
Anatomy & Physiology complement each other and can’t be divorced from one another
Cell theory
All structures and functions result from the activity of cells
Evolution
Human structure can be viewed as a series of levels of complexity
Homeostasis
The purpose of most normal physiology is to maintain stable conditions within the body
Gradient and Flow
Matter and energy tend to flow down gradients.
[End of Chapter 1]
Chapter 2 Chemistry of Life
Introduction – Biochemistry
Biochemistry: the study of the molecules that compose living organisms. Useful for understanding cellular structures, basic physiology, nutrition and health.
Ex: Carbohydrates, fats, proteins, and nucleic acids.
Chemical Elements
Element: simplest form of matter to have unique chemical properties. Made up of protons, neutrons and electrons.
Atomic Number: number of protons in the nucleus of an element.
Periodic Table: List of elements arranged by atomic numbers and represented by one or two letter symbols.
91 naturally occurring elements on Earth, 24 Elements have biological roles
6 elements = 98.5% of body weight: Oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Sodium, chlorine, magnesium, iron.
Trace elements in minute amounts but do not play vital roles.
Minerals: Inorganic elements extracted from soil by plants and passed up food chain to humans. They are important for body structure (calcium) with teeth, bones, ect. Important for enzyme’s functions as cofactors: zinc, copper and magnesium.
Calcium, phosphate, magnesium, fluoride, potassium, chlorine, sodium and sulfate.
Electrolytes: mineral salts needed for nerve and muscle function
Atomic Structure
Atoms were a philosophical concept until the early 1800s. John Dalton
· Atoms are electrically neutral
Nucleus: Center of atom composed of Protons and Neutrons.
Atomic mass: is approximately equal to the total number of protons and neutrons.
· Protons: single positive charge; mass = 1 atomic mass unit (amu)
· Neutron: no charge; mass = 1 amu
Ex: 6 protons and 6 neutrons has an atomic mass of 12
Electrons: Single negative charge with extremely low mass, swarm around in concentric clouds surrounding nucleus called electron shells. The number of electrons is equal to the number of protons.
· Valence Electrons: orbit in the outermost shell and determine chemical bonding properties of an atom.
Isotopes: varieties of an element that differ only in the number of neutrons. Extra neutrons increase atomic weight.
· The isotopes of an element are chemically similar because they have the same number of valence electrons.
Atomic Weight: (relative atomic mass) of an element account for the fact that an element is a mixture of isotopes. Ex: carbon, hydrogen
Isotopes and Radioactivity
Radioisotopes: unstable isotopes that decay and give off radiation. Every element has at least one radioisotope.
Radioactivity: process of decay
Ionizing radiation: Intense radiation can be ionizing (ejects electrons, destroys molecules and creates free radicals) and can cause genetic mutations and cancer.
Ex: UV radiation, x-rays, alpha particles, beta particles, gamma rays.
Physical half-life of radioisotopes is the time required for 50% of decay to a stable state.
Ex: 1 gram of Strontium has a half-life of 28 years, in 56 years sill have 25% in 84 years 12.5% would still have radiation.
The biological half-life of radioisotopes is the time required for 50% to disappear from the body.
Ions, Electrolytes and Free Radicals
Ions: Charged particles (atom or molecule) with unequal number of protons and electrons. Ions with opposite charges are attracted to each other. Forms when atoms give up valence electrons and when other atoms gain electrons.
Ionization: transfer of electrons from one atom to another. Ex: Sodium and Clorine
Anion: a particle that gains electron(s) (net negative charge) -
Cation: particles that loses electron(s) (net positive charge) +
Electrolyte importance
Electrolytes: substances that ionize in water and form solutions capable of conducting electric current.
Chemical reactivity, osmotic effects, electrical excitability of nerves and muscles.
Electrolyte balance is one of the most important considerations in patient care. Imbalance can lead to coma or cardiac arrest.
Free Radicals
Free Radicals: unstable short-lived particles with an unusual number of electrons. They are produced by normal metabolic reactions, radiation, certain chemicals and trigger reactions that destroy molecules, and can cause cancer, death of heart tissue and aging.
Antioxidants: Chemicals that neutralize free radicals.
Superoxide Dismutase (SOD) is an antioxidant enzyme in the body.
Selenium, vitamin E, Vitamin C, and carotenoids are antioxidants obtained through the diet.
Molecules and Chemical Bonds
Molecule: Chemical particles composed of two or more atoms united by a chemical bond.
Compound: Molecule composed of two or more different elements.
Molecular Formula: Identifies constituent elements and how many atoms of each are present. EX: List of ingredients in a recipe.
Structural Formula: Identifies location of each atom. Different relationship of atoms within the molecule. EX: how the ingredients are applied.
Isomer: molecules with identical molecular formulae but different arrangement of their atoms.
Chemical Bonds: hold atoms together within a molecule or attract one molecule to another.
Ionic bonds, covalent bonds, hydrogen bonds, van der walls forces.
Ionic bonds
· Electrons donated from one atom to another
· Attractions between anions and cations ex:NaCl
· Easily broken by water.
Covalent Bonds
· Bonds between atoms that share electrons. Electrons NOT given away or accepted from other atoms.
· Majority of molecules associated with living things are composed of single or double covalent bonds between C, H, O, N, S, and P
Ex: Single bond H2 H--H
Ex: Double bond: CO2 O=C=O
Nonpolar Bond: Electrons shared equally and is the strongest bond.
Ex: CH4, H2, O2. C2 is C--C
Polar Bonds: Electrons shared unequally spending more time near oxygen or nitrogen
Ex: H2O, NH2 OH is O—H
Hydrogen Bond: is a weak attraction between a slightly positive hydrogen atom in one molecule and slightly negative oxygen or nitrogen atom in another. Important to physiology.
Water molecules are attracted to each other by hydrogen bonds.
Large molecules (DNA and Proteins) are shaped by hydrogen bonds within them.
Hydrogen Bond of Water
Van Der Waal Forces: weak, brief attractions between neutral atoms.
· Fluctuations in the electron density within an atom create polarity for a moment and attracts adjacent atoms of a very short time.
· Only 1% as strong as covalent bond but important in the physiology of protein folding.
Water and Mixtures
Water is 50-75% of body weight depending on age, sex, fat content ext.
Mixture: physically blended but not chemically combined.
Body fluids are complex mixtures of chemicals, mostly chemicals dissolved or suspended in water.
Water
Polar covalent bonds and a V-shaped molecule gibe water a set of properties that account for it’s ability to support life:
· Solvency
· Cohesion
· Adhesion
· Chemical reactivity
· Thermal Stability.
Solvency: ability to dissolve other chemicals. Water is called the universal solvent.
· Metabolic reactions depend on solvency of water.
Hydrophilic: “water loving,” substances that dissolve in water. Molecules must be polarized or charged. Ex: sugar.
Hydrophobic: substances that DO NOT dissolve in water. Molecules must be nonpolar or neutral Ex: Fats.
Water and Hydration Spheres:
Cohesion: tendency of like molecules to cling to each other. Water is very cohesive due to it’s hydrogen bonds.
Surface film on surface of water is due to molecules being held together by surface tension.
Adhesion: tendency of one substance to cling to another. Water adheres to large membranes reducing friction around organs.
Chemical reactivity: ability to participate in chemical reactions.
· Water ionizes into H+ and OH-
· Water ionizes many other chemicals (Acids and salts)
· Water is involved in hydrolysis and dehydration synthesis reactions.
Water’s Thermal Stability: helps stabilize the internal temperate of the body. Water has a high heat capacity: (the amount of heat required to raise the temp of 1 g of a substance by 1 degree C.
· Calories (Cal): the amount of heat that raises the temp of 1 g of water 1 degree C.
o Hydrogen bonds inhibit temp increase by inhibiting molecular motion.
· Effective coolant
o 1ml of perspiration removes 500 calories.
Solutions, Colloids, and Suspensions
Solution: consist of particles called the solute mixed with more abundant substance (usually water) called the solvent.
Solute: can be gas, solid or liquid
Solutions are defined by the following properties:
· Will pass through most membranes
· Will NOT separate on standing
Colloids: in the body are often mixtures of proteins and water. Many can change from liquid to gel states within and between cells
· Particles range from 1-100 nm in size
· Scatter light and are usually cloudy
· Particles too large to pass through semipermeable membrane
· Particles remain permanently mixed with the solvent when mixture stands.
Suspension: ex: blood cells suspended in plasma.
· Particles exceed 100 nm
· Too large to penetrate selective permeable membranes
· Cloudy or opaque in appearance
· Separates on standing
Emulsion: Suspension of one liquid in another.
Ex: fat in breast milk is an emulsion
Acids Bases and pH
pH: is a measurement derived from the molarity of H+ . a Change of 1 number on the pH scale represents a 10 fold change in H+ concentration. pH of 4.0 is 10 times as acidic as one of 5.0
· pH of greater than 7.0 is a basic solution (OH->H+)
· pH of 7.0 is neutral (H+ = OH-)
· pH <7.0 is acidic (H+>OH-)
Acid: is a proton donor (ex: releases H+ ions in water)
Base: is a proton acceptor (accepts H+ ions). Many bases release OH-
Ph- measurement of molarity of H+ ([H+]) on a logarithmic scale:
-pH=-log[H+] thus pH=-log[10^-3] =3
Buffers: chemical solutions that resist changes in pH
Ex: maintaining normal (slightly basic) pH if blood is crucial for physiological functions.
Energy and Chemical Reactions
Energy: Capacity to do work. All body activities are forms of work.
Potential energy: energy stored in an object but not currently doing any work. Ex: water behind a dam.
· Chemical Energy: potential energy in molecular bonds.
· Free energy: potential energy available in a system to do useful work.
Kinetic Energy: energy of motion, doing work. Ex: water flowing through dam generating electricity.
Heat: kinetic energy of molecular motion
Electromagnetic energy: the kinetic energy of moving “packets,” of radiation called photons.
Classes of Chemical Reactions
Chemical reaction: a process in which a covalent or ionic bond is formed or broken
Chemical equation: symbolizes the course of a chemical reaction
Reactants on the left à Products on the right.
Classes of chemical reactions:
Decomposition reactions
Synthesis reactions
Exchange reactions
Decomposition reactions: large molecule breaks down into two or more smaller ones
AB = A+B
Synthesis reactions: two or more small molecules combine to form a larger one
A+B = AB
Exchange reactions: two molecules exchange atoms or groups of atoms
AB+CD = ABCD = AC+BD
Ex: Stomach acid (HCl) and sodium bicarbonate (NaHCO3) from the pancreas combine to form NaCl and HcCO3
Reversible reactions: can co in either direction under different circumstances. Symbolized by double headed arrow. Reaches equilibrium when ratio of products to reactant is stable.
o Ex: CO2+H2O H2Co3 HCO3- + H+
o Are important reactions in respiratory, urinary, digestive physiology
Reaction Rates
Reactions occur when molecules collide with enough force and correct orientation.
Reaction rates increase when reactants are more concentrated, temperatures rise, or a catalyst is present.
· Enzyme catalysts bind to reactants and hold them in orientations that facilitate the reactions.
· The catalyst is not changed by the reaction and can repeat the process frequently.
Metabolism, Oxidation and Reduction
Metabolism: all chemical reactions of the body
Catabolism: Energy releasing (exergonic) decomposition reactions.
Breaks covalent bonds and produces smaller molecules.
Anabolism: Energy storing (endergonic) synthesis reactions.
Requires energy input production of proteins or fat.
Catabolism and anabolism are inseparably linked:
· Anabolism is driven by energy released by catabolism.
Oxidation
Oxidation: a chemical reaction in which a molecule gives up electrons and releases energy. Molecules oxidize in this process. Electron acceptor molecule is the oxidizing agent: Oxygen in soften involved as the electron acceptor
Reduction: any chemical reaction in which a molecule gains electrons and negeri. The molecule is reduced when it accepts electrons. A molecule that donates electron is the reducing agent.
Oxidation-reduction (redox) Reaction: oxidation of one molecule is always accompanied by reduction of another.
· Electrons are often transferred as hydrogen atoms.
Carbon Compounds & Functional Groups
Carbonic chemistry: the study of compounds containing carbon
4 categories of Carbon compounds:
1. Carbohydrates
2. Lipids
3. Proteins
4. Nucleic acids
Carbon
Carbon has 4 valence electrons that bind with other atoms that can provide it with four more electrons to fill it’s valence shell. Carbon atoms bind readily with each other to form carbon backbones that carry a variety of functional groups.
· Form long chains, branched molecules and rings and covalent bonds with hydrogen, oxygen, nitrogen, sulfur and other elements.
Carbon’s Functional Groups: small clusters of atoms attracted to carbon backbone.
Ex: Hydroxyl, methyl, carboxyl, amino, phosphate
Macromolecules: very large organic molecules with high molecular weight
Polymers: macromolecules made of repetitive series of identical or similar subunits (monomers)
Polymerization: joining monomers to form a polymer.
Dehydration synthesis (condensation) is how living cells form polymers
A hydroxyl (-OH) group is removed from one monomer and a hydrogen (-h) from another producing water as a byproduct
Monomers covalently bind together to form a polymer with the removal of a water molecule.
Hydrolysis: Digestion; the opposite of dehydration synthesis
· A water molecule ionizes into -OH and -H
· The covalent bond linking one monomer to the other is broke
· The -OH is added to one monomer
· The -H is added to the other
· Splitting a polymer by addition of a water molecule.
Carbohydrates
Names of carbohydrates often built from the root “Sacchar-“ and the suffix of “ose” both meaning sugar, sweet.
Hydrophilic organic molecule- Ex: Sugars and starches.
General formula
· (CH2O)n, n=number of carbon atoms
· Glucose, n=6, so formula is C6H12O6
· 2:1 ratio of hydrogen to oxygen
Three important monosaccharides have the same molecular formula: C6H12O6.
Glucose (blood sugar), galactose, fructose.
o All are isomers of each other.
o Produced by digestion of complex carbohydrates.
Disaccharide: sugar made of 2 monosaccharides
Sucrose: table sugar. Glucose + Fructose
Lactose: sugar in milk. Glucose + Galactose
Maltose: grain products. Glucose + Glucose
Oligosaccharides: short chains of 3 or more monosaccharides (at least 10)
Polysaccharides: long chains of monosaccharides (at least 50) with 3 key examples:
Glycogen: energy stored in cells of liver, muscles, brain, uterus, vagina,
Starch: energy stored in plants that is digestible by humans
Cellulose: structural molecule in plants that is important for human dietary fiber (but indigestible to humans)
Carbohydrates (continued)
· Are quickly mobilized sources of energy.
· All digested carbohydrates converted to glucose
· Oxidized to make ATP
Conjugated carbohydrates: covalently bonded to lipid or protein moiety.
Glycolipids: external surface of cell membrane
Glycoproteins: external surface of cell membrane. Mucus of respiratory and digestive tracts.
Proteoglycans: more carbohydrate than protein.
· Gels that hold cells and tissues together
· Gelatinous filler in umbilical cord and eye
· Joint lubrication and cartilage texture.
Lipids
· Hydrophobic organic molecules with a high ratio of hydrogen to oxygen.
· Have more calories per gram than carbohydrates.
5 primary Types in Humans:
1. Fatty acids
2. Triglycerides
3. Phospholipids
4. Eicosanoids
5. Steroids
Fatty Acids
Chains of 4-24 carbon atoms with carboxyl group on one end and methyl group on the other
Saturated fatty acids: have a lot of hydrogen
Unsaturated fatty acids: contain some double bonds between carbons in chain (potential to add hydrogen)
Polyunsaturated fatty acids: have multi double bonds between carbons in chain
Essential fatty acids must be obtained from food.
Triglycerides (Neutral Fats): primary function is energy storage. Also insulation, shock absorption (adipose tissue)
· 3 fatty acids linked to glycerol
· Each bond formed by dehydration synthesis
· Broken down by hydrolysis
Triglycerides At room temp:
· liquid - called oils, often polyunsaturated fats from plants.
· Solid - called fat, saturated fats from animals.
Phospholipids: Similar to neutral fats except one fatty acid is replaced by a phosphate group.
Structural Foundation of Lipid Cell membrane
Amphipathic: having both hydrophilic and hydrophobic parts.
Fatty acid “tails,” are hydrophobic
Phosphate “head” is hydrophilic
Eicosanoids: 20 carbon compounds derived from arachidonic acid.
Hormone like chemical signals between cells.
Includes prostaglandins: plays a role in inflammation, blood clotting, hormone action, labor contractions, blood vessel diameter.
Steroids
Steroid: a lipid with 17 carbon atoms in 4 rings.
Cholesterol: the parent steroid from which the other steroids are synthesized. Important for nervous system function and structural integrity of all cell membranes.
· 15% of our cholesterol comes from diet
· 85% is internally synthesized mostly in the liver.
Other steroids include: cortisol, progesterone, estrogen, testosterone and bile acids.
“Good” and “Bad” Cholesterol
There is only one kind of cholesterol and it does more good than harm. “Good” and “bad” cholesterol refer to droplets of lipoprotein in the blood.
Complexes of cholesterol, fat, phospholipid, and protein.
HDL (High-Density lipoprotein) “Good” Cholesterol
· Lower ratio of lipid to protein
· May help to prevent cardiovascular disease
LDL (Low Density lipoprotein) “Bad” Cholesterol
· High ratio of lipid to protein
· Contributes to cardiovascular disease
Proteins
Protein- a polymer of amino acids
Amino acid: central carbon with 3 attachments
Amino group (NH2), carboxyl group (-COOH) and Radical (R) Group
20 amino acids used to make the proteins are identical except for the radical group
Properties of amino acid determined by Radical group.
Peptide: any molecule composed of 2 or more amino acids joined by peptide bonds.
Peptide bonds: joins the amino group of one acid to the carboxyl group of the next. Formed by dehydration synthesis.
Peptide name for the number of amino acids
· Dipeptide – 2
· Tripeptide – 3
· Oligopeptide- <10 or 15
· Polypeptides >15
· Proteins >50
Protein Structure
Conformation: unique 3D shape of protein is crucial to their function. Can reverse shape and thus function. Ex: muscle contraction, enzyme catalysis, membrane channeling opening
Denaturation: extreme conformation change that destroys function. Extreme heat, ex: cooking egg.
Primary structure: protein’s sequence of amino acids which is encoded in the genes.
Secondary structure: Coiled or folded shape held together by hydrogen bonds. Hydrogen bonds between slightly negative C=O and slightly positive N-H groups
Most common secondary structures are:
· Alpha helix- spring like shape
· Beta helix pleated ribbon like shape.
Tertiary structure: further bending and folding of proteins into globular and fibrous shapes due to hydrophobic-hydrophilic interactions and van der Waals forces.
· Globular proteins: compact tertiary structures for proteins within cell membrane and proteins that move freely in body fluids.
· Fibrous proteins: slender filaments suited for roles in muscle contraction and strengthening of skin and hair.
Quaternary Structure: occurs in only some proteins like Hemoglobin as 4 peptide chains.
· Association of 2 or more polypeptide chains due to ionic bonds and hydrophobic-hydrophilic interactions.
Protein Functions -Structure
Keratin: tough structural protein of hair, nails, skin surface
Collagen: contained in deeper layers of skin, bones, cartilage, and teeth
Communication Proteins
Some hormones and other cell-to-cell signals are proteins
Ligand: a molecule that reversibly binds to a protein
Receptors: to which signal molecules bind are proteins.
Membrane transport
Channel proteins: in cell membranes that govern what passes
Carriers: transport solutes to other side of membrane
Catalysis most enzymes are globular proteins.
Recognition and protection
· Glycoproteins are important for immune recognition
· Antibodies are proteins
Movement
Motor proteins: molecules with the ability to change shape repeatedly.
Cell adhesion: Proteins bind cells together and keep tissues from falling apart.
Ex: sperm to egg.
Enzymes and Metabolism
Enzymes: proteins that function as biological catalysts. Enzymes lower activation energy.
Energy Activation: energy needed to get reaction started and permit reactions to occur rapidly at body temperature
Enzyme Naming convention
Substrate: substance enzyme acts upon
Named for substrate with “-ase” as the suffix
· Amylase enzyme digests starch (amylose)
Enzyme Structure and Action 1
The Three Steps of an Enzymatic Reaction
Enzyme action—lock and key
1. Substrate approaches enzyme’s active site.
2. Molecules bind together forming enzyme–substrate complex
o Enzyme–substrate specificity
3. Enzyme beaks bonds and release’s reaction products. Enzyme unchanged and can repeat process.
Reusability of enzymes, enzymes are not consumed by the reactions. Astonishing speed and one enzyme molecule can consume millions of substrate molecules per minute.
Changing shape:
Temperature, pH and other factors can change enzyme shape and function which can alter ability of enzyme to bind to substrate
Enzymes vary in optimum pH
Salivary amylase works best at pH 7.0
Pepsin in stomach works best at pH 2.0
Temperature optimum for human enzymes—near body temperature (37°C)
Cofactors: 2/3s of human enzymes require a non-protein cofactor.
· Some are inorganic: Iron, copper, zinc, magnesium and calcium ions.
· Essential to function
Coenzymes: organic cofactors derived from water-soluble vitamins (niacin, riboflavin)
· Accepts electrons from an enzyme in one metabolic pathway and transfers them to an enzyme in another. Ex: NAD+
ATP, Other Nucleotides, and Nucleic Acids
Three components of nucleotides:
4. Nitrogenous base (single or double carbon–nitrogen ring)
5. Sugar (monosaccharide)
6. One or more phosphate groups
Adensosine Triphosphate (ATP)—best-known nucleotide
· Adenine (nitrogenous base)
· Ribose (sugar)
· Phosphate groups (3)
ATP contains adenine, ribose, and three phosphate groups
Adenosine Triphosphate 1
ATP is body’s most important energy-transfer molecule.
· Stores energy gained from exergonic reactions
· Releases it within seconds for physiological work
Holds energy in covalent bonds
Second and third phosphate groups have high energy bonds (~)
Most energy transfers to and from ATP involve adding or removing the third phosphate.
Test review:
Language of terminology prefixes and suffixes.
Cell structure
Need to be able to label fill in the blank
Need to spell out ER:
Scientific method
Gradient and flow- chemicals
Amounts of concentration from high to low. Textbook diagram
Positive and negative feedback
History of terminology.
Chemistry, atomic structures and where they are located
Ion to make a full shell
Vs. isotope difference, varying amount of neutrons
Bonds:
Covalent (sharing)
Polar vs. nonpolar
Ionic bonds
Beg, borrow or steal electrons
Solutions: well mixed
Solvent
Colloid: milky white, bigger particles.
Suspension: will separate out of solution
Acids and bases.
Acids 0-4 higher H
Basic 7-14 lower H
Buffers – maintain pH, ph of blood.
Functional groups- not full molecules but necessary to change shape. Shape change changes function. Methyl, carbolx, ect
Dehydration synthesis- take away water builds bonds
Hydration – add water and breaking bond
Trans fatty acid
Cic fatty acid- broken down
Phospholipid
Levels of protein structure,
Primary, no hydrogen
Flashcards on Anatomy and Physiology
Anatomy: Study of form.
Physiology: Study of function.
Inspection: Examining the body's appearance to identify changes.
Palpation: Feeling with hands to assess conditions like swollen lymph nodes.
Auscultation: Listening to body sounds for abnormalities (e.g., heart, lungs).
Percussion: Tapping on the body to detect abnormal resistance.
Dissection: Cutting apart tissue to understand its relationship.
Medical Imaging: Viewing the inside of the body non-invasively (e.g., X-rays, MRI).
Gross Anatomy: Study of structures visible without a microscope.
Histology: Microscopic examination of tissues.
Histopathology: Examining cells/tissues for disease.
Cytology: Study of individual cells and their functions.
Physiology Subdisciplines: Neurophysiology, Endocrinology, Pathology.
Comparative Anatomy: Studying different species to identify evolutionary trends.
Hippocratic Oath: Ethical guidelines for physicians established by Hippocrates.
Cell Theory: All organisms are composed of cells; cells are the basic unit of life.
Key Concepts in Anatomy and Physiology
Definition:
Anatomy: Study of the structure and form of the body and its parts.
Physiology: Study of the function and processes of the body.
Methods of Examination:
Inspection: Visual assessment of the body.
Palpation: Feeling with hands to identify abnormalities (e.g., swollen lymph nodes).
Auscultation: Listening to internal sounds (e.g., heart, lungs).
Percussion: Tapping on the body to determine resistance.
Dissection: Cutting apart tissue for study.
Medical Imaging: Techniques like MRI and CT scans for internal visualization.
Levels of Structural Organization:
Cells: Basic unit of life.
Tissues: Groups of similar cells performing a specific function.
Organs: Structures composed of two or more types of tissues.
Organ Systems: Groups of organs working together.
Organism: A complete living entity.
Homeostasis: The body's ability to maintain stable internal conditions despite external changes.
Fundamental Principles:
All body functions are interconnected and influenced by the structure and composition of cells and tissues.
Understanding anatomy is essential for interpreting physiological processes.