WGU D312 ANATOMY AND PHYSIOLOGY I OA ACTUAL EXAM COMPLETE QUESTIONS WITH CORRECT DETAILED ANSWERS || 100% GUARANTEED PASS LATEST VERSION

WGU D312 ANATOMY AND PHYSIOLOGY I OA ACTUAL EXAM COMPLETE QUESTIONS WITH CORRECT DETAILED ANSWERS || 100% GUARANTEED PASS LATEST VERSION 1. Levels that make up organism - ANSWER Chemical (Atoms) Cellular (Organelles) Cellular (Cells) Tissue Organ Organ System Organism 2. Homeostasis - ANSWER ability of body to "detect change and activate mechanisms that oppose it" 3. Appropriate phase of homeostasis - ANSWER dynamic equilibrium 4. Mechanisms of maintenance of homeostasis - ANSWER autoregulation (ex. blood flow needs to increase for movement to use hand to write) extrinsic regulation (ex. Nervous and Endocrine systems) 5. Homeostatic regulatory mechanism - ANSWER receptor, control center, effector 6. Types of regulation - ANSWER negative feedback positive feedback negative feedback mechanism - ANSWER opposite condition original positive neglected or reverse turning on and off keeps the variable close to its set point (oscillation) 7. Will shut down the reponse to effect organ to help effect or will turn on ex. shivering; running positive feedback mechanism - ANSWER enhanced enhancement of original condition ex. childbirth; blood clotting 8. Transverse plane - ANSWER Horizontal plane that divides the body into the top and bottom 9. Coronal plane - ANSWER Vertical plane that divides the body into front and back sections 10. Sagittal plane - ANSWER Plane that divides the body into left and right sections 11. 3 types of neurons - ANSWER sensory neurons, interneurons, and motor neurons 12. Sensory or afferent neurons - ANSWER Detect sensory information such as light, pressure, vibration, temp, chemicals, transduce physical and chemical stimuli into electrical signals and transfer info from the periphery towards the CNS for processing. 13. Interneurons also referred to as association neurons - ANSWER located entirely in CNS, located between sensory and motor neurons, integrate and distribute sensory information and coordinate motor output. 14. Motor or efferent neurons - ANSWER Carry impulses or motor commands from CNS to effectors/target organs. Most neurons have dendrites and cell bodies in the CNS and axons that exit the CNS to form peripheral nerves that travel to effectors. 15. Reflex arc - ANSWER the nerve pathway involved in a reflex action including at its simplest a sensory nerve and a motor nerve with a synapse between, happens when an immediate response is needed like touching a hot stove. 16. Glial cells - ANSWER supportive cells of the nervous system, provide structure to the delicate nervous tissue, 6 types of glial cells, 4 types are found in the CNS and 2 types in the PNS. 17. CNS neuroglia - ANSWER Examples are astrocytes; oligodendrocytes; microglia, and ependymal cells. 18. PNS neuroglia - ANSWER The 2 types of glia found only in the peripheral nervous system are satellite cells and Schwann cells. 19. Astrocytes - ANSWER provide a structurally supportive framework for neurons, help form protective blood-brain barrier, maintain the concentration of chemicals in the extracellular space, react to neural tissue damage by forming scar tissue in the damaged space. 20. Oligodendrocytes - ANSWER glial cells of the CNS that wrap and insulate axons and give the CNS white matter its characteristic glossy, white appearance, form myelin sheaths 21. Microglia - ANSWER small highly mobile, phagocytic neuroglia that protect nervous tissue from pathogen infection, remove debris and waste, and may play a role in remodeling of the synapse that occurs during development and with learning. 22. Ependymal cells - ANSWER cuboidal-shaped glial cells that are joined together to form a continuous sheet lining the fluid-filled ventricles and central canal of the brain and spinal cord. Ependymal cells produce and secrete cerebrospinal fluid. 23. Satellite cells of PNS - ANSWER support cells similar to astrocytes, supply nutrients and structural support to the nerves of the PNS. 24. Schwann cells of PNS - ANSWER analog of oligodendrocytes in the PNS, which wrap around nerves of the PNS. 25. Bipolar neurons - ANSWER have a single dendrite extending from one side of the cell body and a single axon extending from the other side, found in the special sense organs for vision and olfaction. 26. Unipolar or pseudounipolar neurons - ANSWER have a single process that emanates from the cell body. The single process has dendrites on one end and the rest of the process is an axon, describes most sensory neurons of the peripheral nervous system 27. Multipolar neurons - ANSWER have 2 or more dendrites on one side and a single axon on the other side of the soma, most common neurons in the CNS. 1 example are motor neurons which have dendrites and somas located in the spinal cord and axons that leave the CNS to innervate skeletal muscles. 28. Anaxonic neurons - ANSWER small, stellate star-shaped cells with processes that all look alike with no apparent axon, can be found in the central nervous system, the retina, and in the adrenal medulla. Their functions are not well understood. 29. Synapse - ANSWER the structure that allows a neuron to pass an electrical or chemical signal to another cell. 30. Meninges - ANSWER The CNS is also covered in multiple protective layers of connective tissue. Inside the skull are the three major meninges: the dura mater, the arachnoid mater, and the pia mater. 31. Cerebrospinal fluid - ANSWER provides additional cushion to the brain and CNS as well as maintaining the extracellular chemical environment. 32. Dura mater - ANSWER is the thickest and strongest of the meninges. 33. Arachnoid mater - ANSWER named for the spider-web appearance acts like a cushion for the brain. 34. Pia mater - ANSWER is a thin membrane that hugs the brain. 35. Meningitis - ANSWER Inflammation of the meninges caused by infection and is extremely severe since the swelling can damage the brain. 36. Cerebrospinal fluid CSF - ANSWER is a clear, colorless liquid produced by ependymal cells lining the ventricles, located primarily between the arachnoid mater and the pia mater, also transports nutrients and wastes in the central nervous system 37. Medulla oblongata - ANSWER most inferior part of the brain, appears as a thickening of the spinal cord. Many of the cranial nerves originate here, controls many basic functions, including the cardiac center, vasomotor center, respiratory centers, and involuntary functions like swallowing, coughing, etc 38. Forebrain - ANSWER actually in the center of the brain, most important structures are the thalamus and hypothalamus. Thalamus is involved in the relay of sensory signals. Hypothalamus controls of the endocrine system 39. What is the outermost layer of the skin called? - ANSWER The epidermis. 40. What type of epithelium composes the epidermis? - ANSWER Keratinized, stratified squamous epithelium. 41. How many layers of cells does "thin skin" have? Name them from superficial to deep - ANSWER Four layers. stratum corneum, (stratum lucidum - only on thick skin), stratum granulosum, stratum spinosum, and stratum basale. 42. What additional layer does "thick skin" have? Where is it found? - ANSWER The stratum lucidum. On the palms of the hands and the soles of the feet (Hairless skin). 43. What lies immediately beneath the epidermis? - ANSWER The dermis. 44. What structures are found in the dermis? - ANSWER Blood and lymph vessels, nerves, hair follicles, and sweat glands. 45. What are the two layers of the dermis? - ANSWER The papillary layer and the reticular layer. 46. What type of tissue makes up the papillary layer? What cells and structures are found in the papillary layer? - ANSWER Loose, areolar connective tissue. Fibroblasts, adipocytes, small blood vessels, phagocytes, lymphatic capillaries, nerve fibers, and Meissner corpuscles. 47. What type of tissue makes up the reticular layer? - ANSWER Dense, irregular connective tissue. 48. What provides elasticity and tensile strength to the skin? - ANSWER Elastin fibers provide elasticity, and collagen fibers provide tensile strength. 49. What is the deepest layer of the epidermis? Also known as the subcutaneous layer or superficial fascia. What function does it serve? - ANSWER The hypodermis. Its functions are fat storage, insulation, and cushioning. 50. What pigments influence the color of skin? - ANSWER Melanin, carotene, and hemoglobin. 51. Where are melanocytes found? - ANSWER Scattered throughout the stratum basale of the epidermis. 52. What are the two primary forms of melanin? - ANSWER Eumelanin (black and brown) and pheomelanin (red). 53. What causes the darkening of the skin or a tan? - ANSWER Accumulation of melanin in keratinocytes due to UV exposure. 54. How does melanin protect the skin? - ANSWER Protects DNA from UV damage and prevents folic acid breakdown 55. What can too much melanin interfere with? - ANSWER Production of vitamin D. 56. Where is carotene stored in the body? - ANSWER In the dermis and subcutaneous layers. 57. What is the sensor called that (tactile corpuscle) responds to light touch? - ANSWER Meissner corpuscle 58. What is the sensor called that (lamellated corpuscle) responds to vibration? - ANSWER Pacinian corpuscle 59. What are the four main types of cells in the epidermis? - ANSWER Keratinocytes, melanocytes, Langerhans cells, and Merkel cells. 60. What percentage of epidermal cells are keratinocytes and what are there functions? - ANSWER Approximately 90% - They manufacture and store the protein keratin, giving hair, nails, and skin their hardness and water resistant properties. 61. What is the role of melanocytes? - ANSWER They produce melanin granules, which absorb UV radiation and contribute to skin color. 62. What is the function of Langerhans cells? - ANSWER They are part of the immune system, recognizing and destroying foreign microbes and presenting their antigens to the immune system. 63. Where are Merkel cells found and what are their role? - ANSWER At the border between the epidermis and the dermal layer. - They function as touch receptors, stimulating sensory nerves that the brain perceives as touch.