Unit 2 Study Guide PDF

Unit 2 Study Guide ================== 1. Epithelial tissue protects the inner and outer surfaces of the body from what? a. Dehydration, abrasion, and destruction by physical, chemical or biological agents 2. List the epithelial tissues that provide anion. b. Stratified sq...

Unit 2 Study Guide ================== 1. Epithelial tissue protects the inner and outer surfaces of the body from what? a. Dehydration, abrasion, and destruction by physical, chemical or biological agents 2. List the epithelial tissues that provide anion. b. Stratified squamous (keratinized and nonkeratinized) c. Transitional d. Pseudostratified 3. Define selective permeability. e. **Selective permeability**: the ability of an epithelium to be non-permeable to some substances while allowing and promoting the passage of other ions and molecules 4. What is moving during filtration and in what direction? What epithelial tissue provides this function? f. **filtration**: fluid moves out of the blood g. Simple squamous epithelium provides this function 5. What are the two types of secretion? h. **Exocrine secretion** (through ducts) i. **Endocrine secretio**n (directly into the blood) 6. List the epithelial tissues that provide secretion. j. Simple cuboidal k. Simple columnar (both ciliated and non-ciliated) l. Pseudostratified columnar (ciliated) m. Goblets secrete n. Cuboidal makes glands which also means secretion 7. What is absorption? What epithelial tissues provide this function? o. **Absorption**: process of taking in substances p. simple cuboidal q. simple columnar (non-ciliated) 8. Which functions of epithelial tissue use energy? Which functions do not? r. **Use energy**: absorption (active transport), and secretion (active process) s. **Don't use energy**: diffusion, filtration 9. Many of the epithelial tissues provide 'movement' as part of their functions. What anatomical structure of the cells is providing this function? t. Cilia on the surface of epithelial cells provide movement 10. What is the function of transitional tissue and where would you find it in the body? u. **transitional tissue** accommodates urine volume changes and is found in the bladder and ureters 11. Which connective tissue**[s]** provide protection to other tissues or organs? v. Dense connective w. Bone 12. Which connective tissue provides the following function: x. Stores energy: adipose y. Resists compression: fibrocartilage z. Resists stress applied in one direction: dense regular a. Forms the fetal skeleton: hyaline cartilage b. Carries oxygen and nutrients to the tissues: blood c. Stores calcium: Bone d. Withstands stresses in all directions: dense irregular e. Provides a framework to lymphatic organs: reticular f. Allows for stretch and recoil: dense elastic g. Maintains shape while being flexible: elastic cartilage h. Contains red marrow: bone i. Transports immune cells and hormones: blood 13. Which type of muscle tissue: j. Has more than one nucleus: skeletal muscle k. Has no striations: smooth muscle l. Can be found in the heart: cardiac muscle m. Is consciously (or voluntarily) controlled: skeletal muscle n. Is used for thermoregulation: skeletal muscle o. Has intercalated discs: cardiac muscle p. Can be found in the hollow organs of the body (list the hollow organs): smooth muscle (stomach, intestines, bladder, blood vessels, uterus) q. Controls the entrances and exits from the body: skeletal muscle r. Controls the size of the blood vessels: smooth muscle i. **Skeletal Muscle**: these muscles are attached to bones and are responsible for movement, posture, and balance, they are striated (have long, thin lines), and under voluntary control ii. **Cardiac Muscle:** these muscles make up the heart and are responsible for pumping blood throughout the body, they are striated and under involuntary control. iii. **Smooth muscles**: found in the walls of hollow organs, such as intestines, liver and pancreas. They are spindle fiber shaped and under involuntary control iv. Types of muscle tissue: MedlinePlus Medical Encyclopedia Image 14. Why do the organs in the body function differently? s. Organs function differently due to the specific types of tissues they contain, which are specialized for particular functions. 15. For each of the eleven organ systems, list the major organs/structures and functions. t. **Integumentary**: skin (protection, temperature regulation) u. **Skeletal**: bones (support, protection, movement) v. **Muscular**: muscles (movement, thermoregulation) w. **Nervous**: brain, spinal cord, nerves (control, communication) x. **Endocrine**: glands (hormone production, regulation\_ y. **Cardiovascular**: heart, blood vessels (transport of nutrients, gases) z. **Lymphatic**: lymph nodes, lymphatic vessels (immune response, fluid balance) a. **Respiratory**: lungs, trachea (gas exchange) b. **Digestive**: stomach, intestines (digestion, absorption) c. **Urinary**: kidneys, bladder (excretion, fluid balance) d. **Reproductive**: ovaries, testes (reproduction, hormone production) 16. What are the four types of membranes in the body? e. Membranes are made of epithelial and bound to connective tissue, types are: v. **Mucous membranes**: line passageways and compartments that open to the external environment (digestive, respiratory, urinary, and reproductive), perform absorptive, and protective/secretory functions vi. **serous membranes**: line body cavities that do not open to external environment and cover external surfaces of many organs, composed of two layers of simple squamous epithelium with fluid between them: produces serous fluid that fills space between the parietal and visceral layers 1. **Parietal layer**: lines the insides of the body cavities 2. **Visceral layer**: covers the surface of the internal organs vii. **cutaneous membrane (skin)**: covers external surface of body, composed of keratinized stratified squamous (epidermis), areolar and dense irregular, provides protection of internal organs from external environments and prevents water loss from body viii. **synovial membrane**: found between articulating bone surfaces, composed of specialized connective tissues, secretes synovial fluid that reduces friction between moving joints 17. Which four organ systems a lined with a mucous membrane? f. Respiratory system, digestive system, urinary system, reproductive system 18. What are the functions of the mucous membrane? What covers the apical surface of the epithelial cells? What is the lamina propria? g. **Function**: protection, lubrication, secretion of mucus h. **Covers the apical surface**: mucus i. **Lamina propria**: a layer of connective tissue beneath the epithelium that supports it 19. What type of membrane is the skin? j. The skin is a **cutaneous** membrane 20. Where would you find synovial membranes? What is the function of synovial fluid? k. **Synovial membranes are found** between articulating bone surfaces (joints) l. Synovial **fluid reduce the friction** between the moving bones 21. Name the three types of serous membranes. Where would you find each? m. **Pericardium**: surrounds the heart n. **Pleura**: lines the thoracic cavity and covers the lungs o. **Peritoneum**: lines the abdominal cavity and covers abdominal organs 22. Which layer of the serous membrane covers the surface of the organ? Which layer lines the inside of the body cavity? What is between these two layers? p. **Covers the organs**: visceral layer q. **Lines the inside of the cavity**: parietal layer r. **Between the layers**: serous fluid 23. What are the two major types of glands? Which one secretes its product into ducts? Which one secretes its product into the blood? s. **Exocrine glands**: secrete into ducts t. **Endocrine glands**: secrete into blood 24. Give an example of a unicellular gland. u. **Unicellular (single celled):** Goblet cells 25. What are acini? v. **Acini**: clusters of cells in the multicellular glands that work together to produce secretion 26. How do simple and compound glands differ? w. **Simple glands**: have a single unbranched duct x. **Compound glands**: have a branched duct 27. Describe the three methods of secretion. Which glands of the body use each? y. **Merocrine glands**: release secretions via exocytosis (ex. salivary glands, sweat glands) z. **Apocrine glands**: release secretions by pinching off the apical portion of the cell (mammary glands) a. **Holocrine glands**: disintegrate the entire cell to release their product (Ex. sebaceous glands) 28\. Define homeostasis. b. **Homeostasis:** the ability of an organism to maintain a stable internal environment in response to changing internal or external conditions. 28. Describe the four components of homeostasis. c. **Stimulus**: a change within the body that causes an imbalance d. **Receptor**: detects the stimulus e. **Control center:** interprets the information from the receptor and initiates changes through the effector f. **Effector**: brings about the change needed to alter the stimulus 29. Describe the homeostatic process the body uses to bring the body temp back down when body temp increases above its 'set point'. g. When body temp rises above the set point, the stimulus is the increased temp. the receptors detect this change. The control center (hypothalamus) interprets the info and signals effectors (sweat glands) to activate. The sweat glands produce sweat, which evaporates and cools the body, bringing the temp back down. 30. What is a 'set point' when talking about negative feedback? What is the purpose of negative feedback in the body? h. **Set point:** the ideal value for a physiological variable that the body tries to maintain ix. the purpose of **negative feedb**ack is to return the variable to its set point 3. the variables tend to fluctuate around the set point they are never constant 4.  31. Why does the graph show the variable going above and below the set point like a wave? i. The graph shows fluctuations around the set point like a wave because the body continuously adjusts the variable, leading to a slight overshoots and undershoots as it stabilizes. 32. Describe the homeostatic process the body uses to maintain blood glucose (both when blood sugar increases and when it decreases). State for each: the stimulus, the receptor, the control center, and the effector. j. **Stimulus**: high blood glucose levels k. **Receptor**: beta cells in the pancreas detect high glucose l. **Control center**: pancreas interprets the information m. **Effector**: pancreas releases insulin, which stimulates the cell to take up glucose, lowering blood sugar levels. x. **When it decreases**: 5. **Stimulus**: low blood glucose levels 6. **Receptor**: alpha cells in the pancreas detect low glucose 7. **Control center**: pancreas interprets the information 8. **Effector**: pancreas releases glucagon, which stimulates the liver to release glucose into the blood, raising blood sugar levels. 33. What is the climactic event when talking about positive feedback? What is the purpose of positive feedback in the body? The graph shows the variable increases over time until when? What happens after this point? n. The climatic event in positive feedback is a significant change or outcome like childbirth. The purpose of positive feedback is to amplify a response until a specific event occurs. The graph shows the variable increasing until the climatic event (birth occurs) after which the body returns to homeostasis xi. **For positive feedback the stimulus is reinforced in the same direction until a climatic event** (ex. uterus contracts to birth baby, contractions release hormones that make contractions stronger and stronger). After climatic event body returns to homeostasis xii. A graph showing a positive feedback Description automatically generated 34. **Positive feedback** is something that like an event that keeps adding on more and more (ex. childbirth, gated channels opening and more Na+ coming in, bladder is getting more and more full, etc) 35. **Negative feedback** is a one time response to a stimulus, it doesn't add on like positive feedback 36. Describe the homeostatic process the body uses when a mother is breastfeeding her child. Be sure to identify the stimulus, the receptor, the control center, and the effector. o. **Stimulus**: baby sucking on the breast p. **Receptor**: sensory receptors in the nipple detect suckling q. **Control center**: hypothalamus interprets info r. **Effector**: pituitary gland releases oxytocin, which stimulates milk ejection from the mammary glands 37. What are the dendrites and the axon of a neuron? What part of the cell body does the axon extend from? s. **Dendrites**: extensions of a neuron that receive signals and detect stimuli. t. **Axon**: long extension that transmits electrical impulses away from the cell body xiii. The axon extends from the axon hillock which is the cell body xiv.  38. What does it mean that a neuron can be excited? What type of 'potential' forms when a neuron becomes excited? u. When a neuron is excited, it means it has responded to a stimulus, leading to a change in its membrane potential. The type of potential that forms is called a **graded potential** 39. What does it mean that a neuron can conduct an electrical charge? What type of 'potential' forms when a neuron is conducting an electrical charge? v. When a neuron conducts an electrical charge, it propagates an electrical signal along its axon w. The type of potential that's forms during this is **action potential** 40. What is secreted from neurons? x. Neurons secrete neurotransmitters, which can have excitatory or inhibitory effects on target cells 41. What two organs make up the central nervous system? y. The central nervous system is made of the brain and spinal cord 42. Describe the two structures that make up the peripheral nervous system. z. The peripheral nervous system is made of: xv. **Nerves**: bundles of neuronal axons extending through the tissue of the body xvi. **Ganglia**: clusters of neuronal cell bodies located along the nerves 43. What is the function of the sensory nervous system? Describe the two divisions. a. The sensory nervous system receives sensory information from receptors and transmits it to the CNS. The two divisions are: xvii. **Somatic sensory**: detects stimuli that can be consciously perceived (ex. senses) xviii. **Visceral sensory**: detects stimuli that are typically not consciously perceived (ex. internal organ conditions) 44. What is the function of the motor nervous system? Describe the two divisions. b. The motor nervous system initiates and transmits motor info from the CNS to effectors. The two divisions are: xix. **Somatic motor**: controls voluntary movements of skeletal muscles xx. **Autonomic motor**: controls involuntary movements of cardiac and smooth muscles, as well as glandular tissues 45. How do sensory and motor neurons differ? What is an interneuron? c. **Sensory neurons**: conduct sensory input towards the CNS d. **Motor neurons**: conduct motor output away from the CNS to effectors e. **Interneurons**: neurons entirely within the brain and spinal cord that receive, process, and store info facilitating communication between the sensory and motor neurons. 46. Describe the structure of multipolar, bipolar, and unipolar neurons. Most interneurons and all motor neurons have what type of structure? Sensory neurons have what two types of structures? f. **Multipolar neurons**: have many dendrites and one axon, most interneurons and all motor neurons are multipolar g. **Bipolar neurons**: have one dendrite and one axon, used in smell, sight and sound h. **Unipolar neurons**: have a continuous dendrite and axon with the cell body off to the side, most sensory neurons are unipolar Lab 1 Neurohistology - Neurons 47. Pumps move substances **against** their gradients while channels allow for the movement of substances **down** their gradients. 48. Describe the three types of channels within a neuron. i. **Leak channels**: always open, allows ions to move freely across the membrane j. **Chemically gated channels**: normally closed, they are open in response to the binding of neurotransmitters k. **Voltage gated channels**: normally closed, open in response to changes in the membrane potential 49. REVIEW from lab 1, for each of the following, state which level of body organization they are: l. **Pumps**: cellular level m. **Neurons**: tissue level n. **Channels**: cellular level 50. What type of organic molecule are pumps and channels made of? o. proteins 51. Describe the 4 segments of a neuron and the pumps/channels found in each. (be sure to state whether the channels are voltage or chemically gated) p. **Receptive segment:** contains chemically gated channels (Na+, K+, Cl-) q. **Initial segment**: contains voltage gated channels (Na+, K+) r. **Conductive Segment**: contains voltage gated channels (Na+, K+) s. **Transmissive segment**: contains voltage gated channels and pumps (Ca++) 52. For each of the following, state which neuronal segment is being described: t. Binds neurotransmitter: receptive segment u. Releases neurotransmitter: transmissive segment v. Propagates (conducts) an action potential: conductive segment w. Initiates the action potential: initial segment x. Generates graded potentials receptive segment 53. REVIEW from unit 1 lecture 5 (slides 19-21): y. Describe the *ionic gradient* that helps to create the resting membrane potential xxi. The RMP is created by the uneven distribution of ions, specifically Na+ and K+ across the membrane. z. The electrical gradient is caused mostly by which organic molecule? What is it about the *structure* of this organic molecule that affects the electrical charge across the membrane? xxii. The electrical gradient is caused by proteins (negatively charged), which cannot cross the membrane affecting the electrical charge a. What type of energy is the resting membrane potential? xxiii. The resting membrane is a form of potential energy b. What is needed to *maintain* the resting membrane potential of a cell? xxiv. The Na/K+ pump is needed to maintain the RMP 54. Describe the two types of graded membrane potentials. Be sure to include whether the potential brings the membrane closer or further from threshold, if it depolarizes or hyperpolarizes the cell membrane and the type of ion movement needed to create each (type of ion moving and direction of movement). c. **Excitatory Post Synaptic Potentials (EPSP):** bring the membrane close to threshold, depolarizing the cell membrane (Na+ moves into the cell) d. **Inhibitory Post Synaptic Potentials (IPSP):** bring the membrane further away from the threshold, hyperpolarizing the cell membrane (K+ moves out or Cl- moves in) 55. What type of channel is used to generate graded potentials? How much ion movement occurs? e. Chemically gated channels, the ion movement is small 56. What type of channel is opened at threshold? What is the voltage for threshold within a neuron? f. Voltage gated Na+ channel is opened at threshold, threshold is -55mv 57. What is the purpose of summation? Describe both spatial and temporal summation. Be sure to include how many presynaptic and postsynaptic neurons are involved in each. g. Summation determines whether the membrane potential reaches threshold xxv. **Spatial summation**: involves multiple presynaptic neurons stimulating at various locations onto the receptive segment of one postsynaptic neuron xxvi. **Temporal summation**: involves a single presynaptic neuron repeatedly releasing neurotransmitter in the same location of one postsynaptic neuron 58. Describe both converging and diverging neuronal pools. (how many pre-synaptic and how many post-synaptic neurons) What type of summation is used by each? What is the purpose of each? h. **Converging**: several presynaptic neurons synapse with one postsynaptic neuron (spatial summation). The purpose is to integrate multiple signals i. **Diverging**: one presynaptic neuron synapses with several postsynaptic neurons (diverging pathways), the purpose is to amplify a signal 59. Once an action potential is generated at threshold, what type of channel is needed to move the action potential to the synaptic knobs? Is there a large or small amount of ion movement during action potentials? j. Voltage gated Na+ channels k. There is a large amount of ions movement during action potentials 60. Describe the ion movement that occurs during depolarization of a neuron. Is this ion a cation or anion? What does this do to the electrical charge inside the cell? l. Na+(cation) moves into the cell making the inside of the cell more positive 61. Describe the ion movement that occurs during the repolarization of a neuron. Is this ion a cation or anion? What does this do the electrical charge inside the cell? m. K+(cation) moves out of the cell making the inside of the cell more negative 62. Draw a graph of the action potential. Be sure to include the three important membrane potentials, the use of chemically/voltage gated channels, when these channels are stimulated to open/close, the ion movement (what ions are moving, when are they moving, and which direction are they moving) and label the graph using depolarization, repolarization and hyperpolarization. n.  63. REVIEW from unit 1: Why does sodium move into the cell? Why does potassium move out? How would a smaller gradient affect the speed of their movement? o. The sodium moves into the cell due to the concentration gradient (the higher concentration of sodium outside the cell, so the Na+ diffuses inside the cell) and electrical gradient (the inside of the cell is more negative than the outside at rest, opposites attract). p. Potassium leaves the cell due to its concentration gradient (there is higher concentration inside of the cell so it moves out), a smaller gradient would slow down the speed of their movement 64. Why does the neuron become hyperpolarized? q. The neuron becomes hyperpolarized due to the K+ channels being slow to close, allowing more potassium to leak out then needed. 65. Why is the Na+/K+ pump needed to bring the neuron back to RMP? 66. During the absolute refractory period of a neuron, what state are the voltage-gated sodium channels in? When does the absolute refractory period begin? When does it end? r. voltage-gated Na+ channels are inactive state. s. It begins when the VG Na+ channels are already activated or inactive (but not resting), the Na+ channels become activated at threshold and inactive at 30+, they do not return to resting until the neuron returns to RMP. 67. During the relative refractory period of a neuron, what state are the voltage-gated sodium channels in? Why does it take a greater stimulus to stimulate the neuron? When does the relative refractory period begin? When does it end? t. Voltage gated sodium channels are in the rested state. A greater stimulus is needed because the membrane is hyperpolarized, making it further away from the threshold. It begins after the absolute refractory period and ends when the membrane is at rest. 68. List the four types of glial cells in the CNS and their functions. u. **Astrocytes**: form the blood-brain barrier, regulate fluid composition, provide structural support, and assist in neural development v. **Ependymal Cells**: line the internal cavities of the brain and spinal cord, and help produce CSF w. **Microglia**: act as phagocytic immune cells that protect the brain from infection and remove debris from dead or damaged tissue x. **Oligodendrocytes**: insulate axons in the CNS by forming myelin sheaths, which facilitate faster action potential propagation 69. List the two types of glial cells in the PNS and their functions. y. **Satellite cells:** electrically insulate neuronal cell bodies in ganglia and regulate nutrient/waste exchange z. **Schwann Cell** (neurolemmocytes): wrap around and insulate axons in the PNS to form myelin sheaths 70. What is myelin and which two glial cells make it? What part of the neuron does myelin cover? What are neurofibril nodes? What is the function of myelin? a. **Myelin**: an insulating covering around the axons made on concentric layers of glial cell plasma membrane xxvii. Myelin functions in increasing the speed of action potential propagation along the axon xxviii. Oligodendrocytes in the CNS and Schwann cells in the PNS make them b. Myelin covers the axon c. **Neurofibril** nodes: gaps between myelin sheaths and where the axon is exposed 71. Describe the process of continuous conduction. In comparison to saltatory conduction, which one is faster? d. **Continuous conduction**: occurs in unmyelinated axons where the voltage gated Na+ and K + channels open sequentially along the entire length of the axon xxix. Continuous conduction is slower than saltatory conduction 72. Describe the process of saltatory conduction. (be sure to include how sodium and neurofibril nodes are involved) e. **Saltatory conduction**: occurs in myelinated axons where action potentials jump from one neurofibril node (node of Ranvier) to another xxx. Na + ions move through the cytosol at the nodes, allowing the action potential to jump and propagate faster down the ion 73. Describe the difference between pre and post synaptic neurons. Are neurons the only cells of the body that can be post synaptic? f. **Pre-synaptic neurons**: neurons that release neurotransmitters g. **Post synaptic neurons**: neurons that receive neurotransmitters xxxi. Other cells like muscle cells and gland cells can also be post synaptic 74. What are neurotransmitters and where are they stored within a neuron? h. **Neurotransmitters**: chemicals that transmit signals from one neuron to another or to other types of cells xxxii. They are stored in the synaptic vesicles within synaptic knobs 75. Describe the process of nerve transmission. Be sure to include the type of channel involved, ion movement, type of membrane transport used to release neurotransmitter and what happens once the neurotransmitter has been released from the synaptic knobs. i. **Action potential**: arrives at the synaptic knob, causing the membrane potential to become more positive j. **Channel involvement**: voltage gated calcium channels open, allowing Ca2+ ions to flood into the synaptic knob k. **Ion Movement:** Ca2+ binds with receptor proteins on synaptic vesicles causing them to fuse with the plasma membrane l. **Membrane transport**: neurotransmitters are released via exocytosis into the synaptic cleft m. **Post release**: neurotransmitters diffuse across the cleft and bind to receptors on the post synaptic cell 76. What is the difference between a direct and an indirect action of a receptor? Give an example of each. What type of graded potential can be generated by both? n. **Direct action**: receptors that directly open ion channels (ex. Nicotinic, ACh receptors causing Na + channels to open, leading to an excitatory postsynaptic potential, EPSP) o. **Indirect action**: receptors that activate G proteins to open ions channels (ex. muscarinic Ach receptors can either cause either EPSP or IPSP depending on the cell type) 77. Why must neurotransmitters be removed from the synaptic cleft after being released? What are the two ways within which neurotransmitters are removed from the synaptic cleft? p. To stop continuous stimulation of IPSP xxxiii. The two ways are: enzymatic breakdown within the synaptic cleft, diffusion back into surrounding cells or glial cells 78. Now let's put the entire nerve transmission together. Describe what occurs *from the moment a Acetylcholine binds a nicotinic receptor* on a neuron *to the* point the neuron *releases neurotransmitter*. Include: q. all potentials (resting, graded, threshold, action) r. all ion movements (Na^+^, K^+^) (in or out of neuron) s. the types of channels used (chemically, voltage) t. the part of the neuron being affected (dendrites, axonal hillock, axon, synaptic knobs) u. the type of membrane transport needed to release neurotransmitter v. and anything else you find important to include 9. **Binding of Ach**: Ach binds to nicotinic receptors on the posy synaptic neuron 10. **Membrane potentials:** a. Resting potential: -70 mv b. Graded potential: depolarization due to Na + influx c. Threshold potential: reaches -55 mV, triggering an action potential d. Action potential: rapid depolarization and repolarization occur 11. **Ion movements** e. Na + influx: through chemically gated channels upon Ach binding f. K + efflux: though the voltage gated K+ channels during repolarization 12. **Channels used:** g. Chemically gated channels for Ach binding h. Voltage gated channels for Na+ and K+ during action potential 13. **Affected parts of neuron:** i. Dendrites (ACh binding), axonal hillock (action potential initiation), axon (propagation), synaptic knobs (neurotransmitter release)