Human Physiology Lecture 1 PDF

Human physiology: Introduction & organizing principles Syllabus  Grading Grading scheme All % scores will be rounded to the nearest whole number (i.e.,...

Human physiology: Introduction & organizing principles Syllabus  Grading Grading scheme All % scores will be rounded to the nearest whole number (i.e., 90.4 would round down to 90, and 90.5 would round up to 91). Midterm 100 points % Letter grade 95-100 A Final exam 120 points 90-94 A- Lecture participation 30 points 87-89 B+ Quizzes (8x 10 points each) 80 points 84-86 B Active learnings (7x 10 points each) 70 points 80-83 B- Total 400 points 77-79 C+ 74-76 C 70-73 C- 67-69 D+ 63-66 D 60-62 D- 0-59 F Lecture Participation Participation can take form in various ways and will be announced in class. Please bring paper & something to write with to class. Lecture Notes Lecture slides will be available on Canvas, in both PowerPoint and pdf formats the day before each lecture. Slides do not contain all the material presented in class and will not make sense in isolation – attendance at class is required. Quizzes Quizzes (multiple-choice, 10 questions each) will be posted on Canvas under “quizzes” Quizzes. Please pay attention to the schedule and when they are open and when they are due! No unexcused make-ups are allowed! The answers will be available to you once you complete the quiz. Exams Sample exam questions will be posted in advance of each exam. The exams will be multiple choice, matching, and short-answer responses. Questions will be based on material presented in lectures and will require skills developed in discussion sections (i.e., application of concepts). You are allowed one page 8.5"x11", front and back, HAND-WRITTEN notes sheet for the exams. It must be turned it at the end of the exams. The final exam is partially cumulative – topics from the first half of quarter that will be on the final will be highlighted in class. Requests for re-grades will be accepted for only one week after exams are returned. To have your exam re-graded, you must submit your concerns in writing to your TA or professor. Do not request regrades until you have looked over the key. Keys will be made available to you once everyone has completed the exam. Lecture 1 Introduction & review of basic concepts Physiology It is an integrative science. The integration of function across many levels of organization is a special focus of physiology. Physiology The study of Physiologists are interested in how parts of the body work together at various levels of organization and in the whole organism. Major themes of physiology 1. Structure and function across all levels of organization 2. Energy transfer, storage, and use 3. Info ow, storage, and use within single organisms and w in a species of organism 4. Homeostasis and the control system that maintains it 5. Evolution Elements of Life Carbon (C): 18.5% 25 essential elements Oxygen (O): 65.0% Four elements make up about Calcium (Ca): 1.5% 96% of the weight of most cells Phosphorus (P): 1.0% Potassium (K): 0.4% (THE BIG FOUR): Sulfur (S): 0.3% Sodium (Na): 0.2% Chlorine (Cl): 0.2% 1. Oxygen Hydrogen (H): Magnesium (Mg): 0.1% 2. Carbon 9.5% Trace elements: less than 0.01% 3. Hydrogen Boron (B) Manganese (Mn) Chromium (Cr) Molybdenum (Mo) 4. Nitrogen Nitrogen (N): 3.3% Cobalt (Co) Selenium (Se) Copper (Cu) Silicon (Si) Fluorine (F) Tin (Sn) Iodine (I) Vanadium (V) Iron (Fe) Zinc (Zn) Basic Structure of an Atom What three subatomic particles make up an atom? Where are they located? What are their charges? Protons(+) —>Nucleus of the atom Neutrons (neutral) 2 Protons Electrons (-). —-> Electron Cloud 2 Neutrons 2 Electrons Nucleus 2e– What makes the atom of one element Electron cloud different from the atom of another element? Electrons of an Atom Electrons are organized in electron shells Outer electron shell is the most important – Full outer electron shell = Stable atom First electron shell Outer electron shell (can hold 2 electrons) (can hold 8 electrons) Electron Hydrogen (H) Carbon (C) Nitrogen (N) Oxygen (O) Atomic number = 1 Atomic number = 6 Atomic number = 7 Atomic number = 8 Number of electrons in the outer electron shell determines how an atom will interact with other atoms Chemical Bonds Atoms lose, gain, or share electrons in order to fill their outermost electron shell Water molecule Atoms (elements) react with other atoms to form molecules Types of Chemical Bonds + - Ionic Bonds Na Cl Na Cl Sodium atom Chlorine atom H O H Covalent Bonds Video Ionic Bonds Ionic bonds: oppositely charged ions attract Ion: an atom with an electrical charge due to gain or loss of electron(s) Complete outer shells Na Cl Na+ Cl– Na Cl Na+ Cl– Sodium atom Chlorine atom Sodium ion Chloride ion Sodium chloride (NaCl) Covalent Bonds Covalent bonds: two atoms share one or more electrons Strongest bond Electron sharing Are electrons always shared equally? H O H Why not? Atoms joined into a molecule via covalent bonds Electronegativity Electronegativity = an atom’s ability to attract electrons The positively charged protons in the nucleus attract the negatively charged electrons. As the number of protons in the nucleus increases, the electronegativity or attraction will increase. Therefore, electronegativity increases from left to right in a row in the periodic table. Types of Covalent Bonds Nonpolar covalent bond = equal sharing of electrons (no charges) Polar covalent bond = unequal sharing of electrons (partial charges) Water Molecule A very important polar molecule = H2O (water molecule) Slightly + (slightly +) Slightly + (slightly +) H H O (slightly Slightly−) - Video Water molecules Hydrogen bonds: Weak electrical attraction between neighboring water molecules Give water unique properties Hydrogen bond Slightly positive charge Slightly negative charge Origin of Life (Molecules of Life) What are the molecules of life? Macromolecules: Large molecules found in all living creatures Organic molecules = carbon-based molecules Carbon Most important element for life Double bond Forms large, Carbon skeletons vary in length Carbon skeletons may complex, and diverse have double bonds, which can vary in location molecules necessary for life’s functions Carbon skeletons may be Carbon skeletons may unbranched or branched be arranged in rings What are the molecules of life? Macromolecules include: 1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic Acid Overview of Macromolecules Most macromolecules have a unique monomer Monomers: building blocks or subunits Monomers are linked together through covalent bonds to produce a polymer via dehydration reactions. http://catalog.flatworldknowledge.com/bookhub/4309?e=averill_1.0-ch12_s08  Macromolecules (DNA & RNA) (sugars) (fats, waxes) (amino acids) Overview of Macromolecules Macromolecule Monomer Carbohydrates Monosaccharides Lipids None Proteins Amino Acids Nucleic acids Nucleotides Monomers are primarily composed of: carbon, hydrogen, oxygen and nitrogen Carbohydrates Carbohydrates function as: Source of dietary energy Material for manufacturing other organic compounds Structural support in plants Plant cell walls are made of cellulose, which is a carbohydrate Lipids – Fats Fats have two subunits (amphipathic molecule): 1.Glycerol head 2.Three fatty acid tails (C-H chain) Functions in the human body: long term energy storage cushioning insulation Triglyceride Saturated vs. Unsaturated Fats Fatty acid tails can be saturated or unsaturated Trans fats are liquid fats that are converted to solid fats during food processing techniques. Lipids – Steroids Very different from fats in structure and function Ringed structure Cholesterol a key component Cholesterol can be converted by the body to of cell membranes body uses it to produce sex hormones Testosterone A type of estrogen Proteins Very diverse in structure and function Functions: structural support, contraction, transport, chemical reactions (enzymes), etc. Nucleic Acids Monomer: Nucleotides Gene Functions: DNA store genetic Nucleic information acids provide instructions RNA for building proteins Polymers: Amino acid DNA (DeoxyriboNucleic Acid) Protein RNA (RiboNucleic Acid) Origin of Life – Summary Small molecules Cells Elements Macromolecules (alive) and monomers  Levels of Cell Organization Cellular Di erentiation: The normal process by which an unspecialized cell becomes specialized into one of the many cell types that make up the body. Levels of Cell Organization Levels of Cell Organization Muscle Cells & Tissues Specialization to contract and produce force 3 types of muscle cells 1. Cardiac (involuntary) 2. Skeletal (voluntary) 3. Smooth (involuntary) Neurons & Nervous Tissue A neuron is a cell of the nervous system specialized for cell-to- cell communication (initiation, integration and conduction of electrical signals). Collection of neurons forms nervous tissue (brain/spinal cord) Axons from many neurons packages plus connective tissue (CT)= nerve They come in many shapes & sizes Epithelial Cells & Tissues Epithelia are located at the surfaces that cover the body or individual organs, and they line the inner surfaces of the tubular and hollow structures within the body. Epithelial cells are specialized for the Selective secretion and absorption Of ions and organic molecules, and for protection Name Description Simple Single cell layer thick Stratified Multiple cell layers thick Cuboidal Cube-shaped Columnar Column-shaped, elongated Squamous Flattened Ciliated Possessing cilia Connective Tissue Cells Connective tissue cells are specialized to Connect, anchor, and support the structures of the body Types of connective tissues include: Loose Connective Dense Connective Blood Bone Cartilage Adipose What surrounds the cells? The immediate environment that surrounds each individual cell in the body is the extracellular fluid and extracellular matrix (ECM). ECM consists of a mixture of proteins, polysaccharides, and in some cases, minerals. The proteins of the extracellular matrix consist of fibers—ropelike collagen fibers and rubberband-like elastin fibers—and a mixture of nonfibrous proteins that contain carbohydrate. The matrix serves two general functions: 1. It provides a scaffold for cellular attachments 2. Transmits information, in the form of chemical messengers, to the cells to help regulate their activity, migration, growth, and differentiation. Organs & Organ Systems Organs are composed of multiple tissue types (example: blood vessels have layers of smooth muscle cells, endothelial cells and fibroblasts). Organ systems contain multiple organs that work together (example: the urinary system has the kidney, ureters, urethra, bladder). 11 Different Organ Systems! Bodily Fluids & Compartments The term “body fluids,” is used to refer to the watery solution of dissolved substances (oxygen, nutrients, etc.) present in the body. The fluid in the blood and surrounding cells is called Extracellular uid (i.e., outside extracellular fluid the cell). 20–25% fluid portion of blood (plasma) 75–80% lies around & between cells and is known as the interstitial fluid. Bodily Fluids & Compartments Intracellular uid inside the body The composition of the extracellular fluid is very different from that of the intracellular fluid. Maintaining differences in fluid composition across the cell membrane is an important way in which cells regulate their own activity. Bodily Fluids & Compartments Extracellular Fluid  Total Body Water Extracellular Intracellular Fluid Fluid Plasma Interstitial Fluid Composition of Extracellular & Intracellular Fluids