Intro ANAtomy.pdf

101-805 Topic 1: Intro to Biology Pt 1 1. Important definitions 2. Defining Life 3. Body organization 4. Biological hierarchy 5. Homeostasis 6. Homeostatic regulation 7. Feedback pathways 8. Disruption of homeostasis 1.1. Brief Introduction What is BI...

101-805 Topic 1: Intro to Biology Pt 1 1. Important definitions 2. Defining Life 3. Body organization 4. Biological hierarchy 5. Homeostasis 6. Homeostatic regulation 7. Feedback pathways 8. Disruption of homeostasis 1.1. Brief Introduction What is BIOLOGY? 1.1. Brief Introduction What is BIOLOGY? The study of all aspects pertaining to ______!!!! Everything from atoms and molecules, to organisms, to ecosystems, to the biosphere Processes that include metabolism, growth, evolution, ecology… Biology is derived from the Greek word “Bios”, which means “life” and the suffix “logia”, which means “study of” – Coined by Carl Linnaeus, father of taxonomy. 1.1. Brief Introduction What is ANATOMY? The study of bodily __________ Naming / Identification Localisation The “whats” What is PHYSIOLOGY? The study of bodily ___________ Definitions Processes Connections The “hows” What is your body doing, and how? 1.1. Brief Introduction What is METABOLISM? The total of ALL reactions in the body that involve cellular chemical reactions Typically involves usage or liberation of _______ All metabolic pathways in a cell. 1.1. Brief Introduction How do we acquire the What is METABOLISM? raw materials to fuel these pathways? The total of ALL reactions in the body that involve cellular chemical reactions  Two major types ___________ – breakdown __________ – reactions that building RELEASE reactions that energy USE energy 1.1. Brief Introduction What is DIGESTION? 1) The _____________ processing of food from large pieces into smaller pieces Done by: Teeth/tongue, muscle contraction (stomach, intestines), digestive secretions (bile) Purpose: Many small pieces have more total surface area then one large piece; more accessible for chemical alteration 1.1. Brief Introduction What is DIGESTION? 2) The _____________ alteration of food from large molecule chains into smaller molecules Done by: ENZYMES that break down carbohydrates, fats, proteins by breaking chemical bonds Purpose: Component pieces can be absorbed into the body to build new molecules, to provide energy, to provide nutrients 1.1. Brief Introduction So what is ENERGY? In biological systems energy exists as the molecule ADENOSINE TRI PHOSPHATE or ___ (currency of life) Gain ATP by breaking things down aka ____________ Spend ATP to build things aka ___________ ˭ 1.1. Brief Introduction What is CELLULAR RESPIRATION? Also called oxidative respiration because it uses ______ The process your cells use to MAKE ATP (aka energy) Does NOT = breathing Occurs in THREE steps: 1) GLYCOLYSIS 2) KREBS CYCLE 3) ELECTRON TRANSPORT CHAIN + OXYDATIVE PHOSPHORYLATION 1.1. Brief Introduction What is REACTIVITY? The property of a cell/living organism to react to environmental ____________ What is a stimulus? Anything internal or external that a cell/organism can “feel” and that causes a _______: 1.1. Brief Introduction What is REACTIVITY? The property of a cell/living organism to react to environmental stimuli What is a stimulus? Anything a cell/organism can “feel” and that causes a reaction: 1.2. What is life? So how do you know that you are alive How do you know that something else is alive?  1.2. Properties of Life Key characteristics of living organism: 1. _____: precise spatial organization on many levels 2. : maintaining a steady internal state 3. : processes involved in transforming/using energy 4. ____________________: increase in size and/or maturation 5. : an ability to respond to environmental stimuli (internal AND external) 6. ___________________: big ones make smaller ones that look/act similar 7. : change over time to better survive their environment Some factors may be more obvious than others, but ONLY when all criteria are fulfilled do we consider something to be truly alive. 1.3. How is a body organized? The study of life extends from the microscopic scale of molecules and cells to the global We call this step-wise increase scale of an entire in complexity the BIOLOGICAL living planet! _________________. 1.3. How is a body organized? NOT alive YES alive 1.3. How is a body organized? Bodies are organized in levels of increasing complexity: ____________________ level How are the atoms organized? ____________________ level What is the internal organization of the cell, the basic unit of life? ____________________ level How are cells of different types arranged to work together? ____________________ level How are different tissues arranged to work together? ____________________ level How are different organs arranged to work together? ____________________ level How does the entire body work as a whole? 1.3. How is a body organized? As we progress through and up the levels, we will observe a phenomenon called: COMPLEMENTARITY What does this mean? STRUCTURE/FORM = _________ Biological structures at EVERY LEVEL are adapted and specialized to perform specific roles; if something occurs to affect structure, function will be affected too. e.g. Shape of your hand (arrangement of bones, muscles, joints, tendons and ligaments) is perfect for grasping and manipulating objects…imagine if you really were all thumbs… 1.3. How is a body organized? As we progress up the levels, we also observe that at each level of the biological hierarchy there occur properties that are more then the sum of their parts: NOVEL EMERGENT PROPERTIES What does this mean? At each level of complexity the arrangement and interaction of the different components creates NEW properties that were absent (and unanticipated) at the lower levels BECAUSE of this order If I randomly mixed together the “ingredient” atoms making a human being in a jar, I would not end up with a person, I’d end up with sludge E.g. Thinking and conscious are emergent properties of neural organization… E.g. Growth and sexual development are emergent properties of organism organization… 1.4. Biological Hierarchy Let’s start at the beginning, a very good place to start... What is an atom? The smallest unit of matter that is still itself i.e. a carbon atom is the smallest possible amount of carbon. Subunits: Proton (_) charge Found in the centre, making up the Neutron __ charge NUCLEUS of the atom. Electron (_) charge 1.4. Biological Hierarchy Atomic # = how many Atomic mass = how many protons do you have? protons+neutrons do you have? Hydrogen 1 – 1 P Hydrogen 1 – 1 P + 0 N Carbon 6 – 6 P Carbon 12 – 6 P + 6 N Gold 79 – 79 P Gold 197 – 79 P + 118 N 1.4. Biological Hierarchy Going up in size – atoms are the building blocks for creating MOLECULES and COMPOUNDS 2+ atoms bound together 1.4. Biological Hierarchy There are 4 major classes of LARGE biological molecules that make up every living organism…ladies and gentlemen it’s the BIOMOLECULES!!!!!! Monosaccharides Lennon ŒÁ‡ Á€ ÆЀ ¸ Fatty acids McCartney Amino acids Harrison Nucleotides Starr 1.4. Biological Hierarchy These 4 BIOMOLECULES each play a crucial role as building blocks for the MACROMOLECULES 1 2 3 4 1.4. Biological Hierarchy Proteins, carbohydrates, lipids, and nucleotides are important components of living cells Various combinations of these 4 organic (carbon containing) macromolecules make up everything needed to make a cell – BUT remember the hierarchy! Proper organization of these macromolecules is essential Just mixing them up at random would not generate a cell One other important, inorganic ingredient necessary for life??? WATER 1.4. Biological Hierarchy The CELL is the smallest unit of life Proteins, carbohydrates, lipids, and nucleotides are crucial components of EVERY cell (everything suspended in water) Building blocks that create __________ – different structures with different and specific jobs, inside a cell Analogy time: A cell is like a house; the different organelles are like the different rooms, the proteins, carbohydrates, lipids, and nucleic acids are the different types of materials used for construction. Only when it is all built together in the correct shapes can you have a functional house/living cell. 1.4. Biological Hierarchy The CELL is the smallest unit of life 1.4. Biological Hierarchy IMPORTANT NOTE!!!! There are living organisms that are made up of only ONE SINGLE CELL No tissues, no organs, no organ systems…. Can you think of any examples of single celled organisms??? E.g. Bacteria E.g. Archaea E.g. Protozoa Do have organelles!! These are animal-like cells similar to ours. Bacteria and Archaea are extremely simple - don’t have membrane defined organelles! Their internal contents are not compartmentalized – everything inside suspended in cytosolic goop! 1.4. Biological Hierarchy Unicellular organisms have no higher order one cell = whole creature Some have compartments (Protozoans/some Fungi) and some don’t (Bacteria/Archaea) Multicellular organisms contain many cells with different functions that need to be properly ordered UNI/MULTI Includes all Plants and all Animals, some Fungi ALL have compartments in each cell All have organelles aka compartments ____________________ CELLS MULTICELLULAR For the purposes of this course, we will be considering ANIMAL cells as the standard. No organelles i.e. no compartments ___________________ CELLS UNICELLULAR 1.4. Biological Hierarchy A tissue is a collection of cells all working together to perform a specialized function If each cell is a house, a tissue is a neighbourhood, made up of all kinds of different buildings 4 types of tissues in the body: Muscle tissue Neural tissue Epithelial tissue Connective tissue 1.4. Biological Hierarchy An organ is a collection of all 4 tissues working together If each tissue is a neighbourhood, then an organ is a city made up of lots of different neighbourhoods Each organ contains all tissue types in different p proportions Heart Liver Skin Brain… 1.4. Biological Hierarchy An organ system is a group of organs that all contribute to a specific set of larger functions If each organ is a city, then an organ system is a province, made up of a network of interconnected cities 11 organ systems in the body Circulatory Endocrine Reproductive Urinary Respiratory Integumentary Skeletal Muscular Lymphatic Digestive Nervous 1.4. Biological Hierarchy An organism is made up of a set of organ systems all working together to create an individual If each organ system is a province, the organism is a country, made up of multiple semi-independent provinces all overseen by a central authority 1.5. What is Homeostasis? Homeo: unchanging Stasis: standing still The maintaining of a relatively stable internal environment aka internal balance Claude Bernard 1813-1878 “milieu intérieur” 1.5. What is Homeostasis? Things that DISRUPT homeostasis are called ______________ or ____________ Body temp Blood pressure pH Oxygen and carbon dioxide balance Osmotic (water) pressure Solute (dissolved substances) concentrations Our bodies have ideal values for each of these properties called ____________________ Movement away from the set point, i.e. stressor effect, causes the body to respond to maintain homeostasis E.g. What happens if you suddenly do 25 jumping jacks??? 1.5. What is Homeostasis? Why is it a problem if homeostasis is disturbed? Body out of “comfort zone” – too much deviation from steady state can be dangerous How does the body return the internal environment to the set point if homeostasis is disrupted? 1.6. Homeostatic Regulation Five elements required to respond to changes and re-establish homeostasis: 1) A sensory receptor Senses the change i.e. a STIMULUS Each different stimulus has its own sensory receptor e.g. light, sound, taste, smell, temperature, pain, pressure, blood gasses, metabolites, etc. 2) The sensory or afferent pathway (nerve or hormone) Carries the information from the receptor to the control centre 3) Control/integration centre Analyzes and interprets sensory information from receptor and decides on the appropriate response 4) The motor or efferent pathway (nerve or hormone) Carries the information from the control centre to the effector (actor) 5) A motor effector (muscle or gland) Executes the response to the stimulus – performs an action that restores homeostasis 1.6. Homeostatic Regulation Sensory receptor “feels” Stimulus is the _______ the change aka stimulus. Control centre “decides” what action to take. Homeostasis is restored until next time… Motor effector “acts out” the change aka effect. Response is the _______ 1.7. Feedback Pathways There are two directions a homeostatic restoration can go: 1) NEGATIVE feedback Response moves the body _______ from the stimulus Most common 2) POSITIVE feedback Response moves the body _______ the stimulus Quite rare 1.7. Feedback Pathways NEGATIVE feedback Automatic correction E.g. COLD Body acts to conserve body heat, minimize heat loss, increase heat production How? 1.7. Feedback Pathways NEGATIVE feedback Automatic correction E.g. HEAT Body acts to increase heat loss, cool body surface How? 1.7. Feedback Pathways Too hot? Cool you down. Too cold? Warm you up. A negative feedback pathway acts to counteract the original stimulus that caused set point change i.e. FIX THE PROBLEM by _____________ IT. aka _______________. 1.7. Feedback Pathways POSITIVE feedback Reinforces stimulus – used when the body must undergo a stressful/dangerous process that needs to be over quickly and can’t be “avoided” i.e. ripping off the band-aid Not common; acts only in the SHORT TERM Opposite to negative pathway in that here we “_______” to the stimulus to push through and get back to normal i.e. the set point 1.7. Feedback Pathways POSITIVE feedback E.g. BLOOD CLOTTING Body acts fast to prevent blood loss How? Platelets (in the blood) aggregate due to a chemical signal CASCADE Each platelet recruits more platelets aka snowball reaction Lasts ONLY so long as wound is open; then stops 1.7. Feedback Pathways POSITIVE feedback 1.7. Feedback Pathways POSITIVE feedback E.g. CHILDBIRTH Stressful and potentially dangerous; body wants to limit the time under strain How? Mild contractions lead to release of the hormone OXYTOCIN Oxytocin causes contractions to become continually stronger, each contraction stimulates more oxytocin release Hormone release drops off once the baby is born 1.7. Feedback Pathways Question time: The human body has many more negative feedback pathways then positive feedback pathways. Why do you think that is? Do you think that makes sense? 1.8. Disruption of Homeostasis Overall, your body is very good at maintaining homeostasis and bouncing back from a disruption Maintained in a state of ___________________ Dynamic aka always changing Equilibrium aka remaining in balance A little homeostatic disruption is normal  changes signal to your body to help you get/do what you need Can you think of some examples? 1.8. Disruption of Homeostasis However, in some cases the disruption is too great and the body fails in maintaining homeostasis  too far out of “comfort zone” What does this lead to? ______ aka imbalance in homeostasis Can you think of some examples? 1.8. Disruption of Homeostasis Disease / illness occurs due to a FAILURE of homeostasis i.e. body is NOT able to restore dynamic equilibrium can’t reset after a set point disruption As we go through each body system think about what each does and why it’s a problem if it goes wrong When we see examples of illness think about how / where homeostasis failed; this extends through 805 and 806 into all other courses and your career… 1.8. Disruption of Homeostasis Disease / illness occurs due to a FAILURE of homeostasis i.e. body is NOT able to restore dynamic equilibrium can’t reset after a set point disruption As we go through each body system think about what each does and why it’s a problem if it goes wrong When we see examples of illness think about how / where homeostasis failed; this extends through 805 and 806 into all other courses and your career… 1.Summary pt 1 How do we define biology, anatomy, physiology, digestion, metabolism, energy, cellular respiration and irritability? What are the six important characteristics of a living organism? What is meant by the biological hierarchy? What are the levels in the human body? What is complementarity? Why is it important? What are novel properties? Why are they important? What are the four biological building blocks? What larger (macromolecules) do they create? What is the difference between a single (uni)cellular organism and a multicellular organism? Which are we? 1.Summary pt 1 con’t What is body homeostasis? What are set-points? Can you give some examples? What are stressors? What do they do? Can you give some examples? How is homeostasis regulated? What are the elements necessary for homeostatic regulation? What is a negative feedback loop? Can you diagram it using pain? Loud noise? Bright light? What is a positive feedback loop? Can you give an example? Why are they less common? What is the result if the body cannot re-establish homeostasis after disruption?