BIO 101 1nd Edition Lecture 5 Outline of Last Lecture II What is athletic cheating III How are steroids abused by athletes IV How do athletes cheat to increase their endurance V How is human growth hormone abused by athletes VI What might the future of athletic cheating be like Outline of Current Lecture VII Big themes in Biology VIII Organization of Animal Bodies IX Different Animal Tissues X Animal Bodies XI Homeostasis XII Wet Cell Song XIII Essential Nutrients XIV Illnesses caused by infection XV Big Ideas Current Lecture ON TEST no short answer Multiple choice and fill in the blank These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute Only need pencil Will not be tested on ionic and covalent bonding o Not everything in homework will be tested over Study of the animal body involves two related topics Anatomy Structure and organization Physiology how the body works Focus Questions How do animal body structures reflect their functions How do animals regulate their internal environment How does homeostasis work Big Themes in Biology Compartmentalization Internal environment that is different from the outside environment o MSU Example Business Department Cells are compartments that can specialize o Examples Brain cells don t do the same thing as other cells Homeostasis System to detect changes in internal and external environments AND to respond to these changes in order to maintain balance o MSU Example Faculty meetings testing security systems taking roll technology residence halls Organization of animal bodies Cell smallest unit of organization in all organisms Tissues Group of cells that share similar structure and function Organ Group of tissues that perform specialized functions Organ System Group of organs that work together to accomplish one or a few usually related physiological functions In Multicellular organisms one cell doesn t do it all because we have specialization we can grow more o Division of labor and specialization Different Animal Tissues Connective tissue o Composed of cells interspersed throughout a matrix o Provides structure and support anchors cell and regulates communication between cells Epithelial Tissue o Composed of cells that cover and line most surfaces of animal bodies o Forms the skin and the lining of the lungs digestive tract and blood vessels Muscle Tissues o Composed of cells that can contract o Generates movement pumps fluid and moves substances Nervous Tissue o Composed of specialized cells that send and receive electrical signals o Stores and transmits information Epithelial tissue covers most interior and exterior surfaces of the body The surface of your skin Epithelium plays multiple roles in organisms Three of its most important functions are protection transport and secretion Muscle tissue enables movement Nerve tissue 2 types of ells 1 Neurons Transmit a signal 2 Glial Cells Take care of the neurons by providing nutrition structure and protection Identify the system Which system works to support the body and to move it Which systems work to exchange material with the external environment Which systems work to transport materials throughout the body and to defend the body against invasion Which systems work to control and coordinate the body s function in order to maintain homeostasis Which system has the primary responsibility for producing offspring 11 3 Animals internal environment remains relatively constant Your body exchanges chemicals and energy with the environment Even though the environment is variable your body maintains nearly constant internal conditions 11 3 Animal bodies tend to maintain relatively constant internal conditions The tendency to maintain a constant internal environment is called homeostasis Homeostasis is most commonly maintained by negative feedback or less commonly positive feedback As the muscles start moving and that s what make you shiver your muscles start moving they are converting chemical energy into heat energy which brings your temperature up Homeostasis does not just refer to temperature It is important to note that while some groups of organisms called regulators maintain homeostasis for a certain variable other organisms called conformers may have no set point for that variable and the variable may fluctuate with external changes Osmoregulators organisms that maintain their fluids and solute concentrations within narrow ranges that differ from those of their environment 11 3 Homeostasis Negative feedback is a form of regulation in which the result of a process inhibits that very process Positive feedback is a form of regulation in which the results of a process intensify that same process Are these examples of negative or positive feedback Blood clots A damaged blood vessel releases chemicals that attract platelets which pile up and release chemicals until a clot is formed Positive feedback Thirst During exercise Your body uses water in cellular process and sweats to cool itself Negative feedback Blood Glucose levels Eating causes blood glucose levels to rise In response the pancreas releases insulin If glucose levels are too low the pancreas releases glucagon previously stored as glycogen into the bloodstream Negative feedback Food is processed in a series of stages Mechanical Digestion is the use of physical processes to break down food into smaller pieces Chemical Digestion is the use of enzymes to perform hydrolysis chemical reactions that use water to break bonds within large molecules Project Wet Cell Song Hydrolysis Described With water my cells can create things Cells also need water to break things You might wonder what must be broken It s food that s too big for my cells Oh break down break down break down The food into tiny pieces O break down break down break down the food for my cells Dehydration Synthesis described The food in my cells are the makings Of hormones and enzymes I need To help me to grown and to function But without water these wont be made Oh make up makeup Water helps cells make these chemicals Make up makeup Makeup these things that we need 11 4 After Digestion food molecules are absorbed and waste is eliminated Absorption is the uptake of these small nutrient molecules primarily by the cells that line extensive folds in the small intestine Elimination is the disposal of undigested matter from the body 11 5 The alimentary canal starts at your mouth The mouth also