BIOS 252 Final Essay Questions completed with answers

BIOS 252 Final Essay Questions Chamberlain College of Nursing - BIOS 252 Final Essay Questions 1. Define spinal reflex and use an example from the body to illustrate a spinal reflex. (Page 446) Spinal Reflex – when integration takes place in the spinal cord gray matter If you pick up something hot, the grasping muscles may relax and you may drop the hot object even before you are consciously aware of the extreme heat or pain. This is an example of a spinal cord reflex—a quick, automatic response to certain kinds of stimuli that involves neurons only in the spinal nerves and spinal cord. 2. Describe sleep and its major stages and then contrast sleep to coma - how are they similar and how do they differ. (Page 570) Sleep is a state of altered consciousness or partial unconsciousness from which a person can be aroused Coma is a state of unconsciousness in which a person has little or no response to stimuli Alpha waves- stage 1 (drowsy) Sleep Spindles – Stage 2 light sleep Theta and delta waves – stags 3-4 deep sleep Beta waves- fully awake eyes open Brain Waves: Alpha waves – awake and resting Beta Waves – mental and sensory activity Theta Waves – emotional distress Delta Waves – Deep sleep in adults 2. Explain language usage and comprehension including a description of the two major language areas of the brain, where they are located and what they are specialized to accomplish, including what happens when damage occurs to either area. Broca’s Area: Located in the frontal lobe left hemisphere, deals with speaking and understanding language that involve sensory association and motor areas at the cortex Wernicke’s Area: Located in the left temporal & parietal lobes left hemisphere, interprets the meaning of speech by recognizing spoken words, translates words into thoughts Damage to Broca’s: Cerebrovascular accident (CVA) means understand words but cannot speak your thoughts Damage to Wernicke’s: Can speak but cannot arrange words in a coherent fashion 3. Compare and contrast the cochlea and the vestibular apparatus, discussing their anatomical and physiological differences. The inner ear is divided into 2 categories: the cochlea and vestibular apparatus. Cochlea – snail shape boney spinal canal makes 3 turns around a boney cord and divided into 3 channels Vestibular apparatus – is the oval central portion of the boney labyrinth the membranous labyrinth in the vestibule consists of two sacs the utricle and saccule which are connected by a small duct coming from the vestibule are 3 boney semicircular canals 4. Explain the process of light reflecting off an object will pass through the eye. Include all relevant structures and indicate how the photon is transduced into an electrochemical signal in the brain. Include the major regions involved in visual transduction. Light rays reflecting distant objects are focused on the retina after they passed through the cornea, aqueous humor, the lens, and vitreous humor. As light passes through the eye they experience refraction, which is the change in direction of light rays as they transition between different materials. Once the light rays are focused on the retina, the formed image is processed by photoreceptor cells called rods and cones. These photoreceptors relay the signal to the brain by the optic nerve. 6. Explain the control of estrogen and progesterone through the endocrine system. FSH – stimulates follicular cells to secrete estrogen, which is the female sex hormone Both FSH and LH stimulate secretion of estrogen by ovarian cells together estrogen and progesterone prepare uterus for implantation of fertilized ovum and help prepare mammary gland for milk secretion 7. Explain the process of calcium regulation in the body using the concepts of homeostasis and negative feedback The parathyroid glad is the main regulator of calcium. PTH stimulates the release of calcium into the blood from the bones and causes the kidneys to retain calcium from urine and activate Vitamin D that aids in the retention of Ca. The thyroid gland makes calcitonin which removes calcium from the blood and puts it into the bones. 8. How is sugar regulated in the body (both up and down regulation of the molecule in the blood stream) When the body does not convert enough glucose for use, blood sugar levels remain high. Insulin helps the body’s cells absorb glucose, lowering blood sugar and providing the cells with the glucose they need for energy. When blood sugar levels are too low the pancreas releases glucagon. Glucagon forces the liver to release stored glucose which causes the blood sugar to rise. 9. Discriminate between paracrine, autocrine, endocrine and exocrine secretions Autocrine – Hormones that act on the cell that produced them. Paracrine – Hormones are released from cells and bind to receptor on nearby cells and affects their function. Local hormones diffuse a short distance to other cells Endocrine –Secret their hormones into the interstitial fluid surrounding secretory cells Exocrine – Secrete their products into ducts that carry the secretion into body cavities into the lumen of an organ or the sweat glands and sebaceous glands, mucus and digestive glands 10. Describe each endocrine gland and describe the hormone(s) it secretes, the function(s) of the hormone(s) and how the endocrine gland is regulated. Endocrine Gland Regulated by: Secretes Pituitary: Anterior Pituitary Hypothalamus Growth Hormone – cell growth Melanocyte-Stimulating Hormone – Stimulates melanocytes Thyroid-Stimulating Hormone – Controls thyroid activity Follicle- Stimulating Hormone – in males, stimulates testes to produce sperm; in females, initiates development of oocytes and induces ovarian secretion of estrogens Prolactin – promotes milk production of mammary glands Adrenocorticotropic Hormone- increased release of hormone from adrenal cortex Anterior Pituitary Hypothalamus Antidiuretic Hormone – conserves body water by decreasing urine Oxytocin – stimulating contraction of smooth muscle cell during childbirth Thyroid Thyroid-Stimulating Hormone T3/T4 – Helps with metabolism Calcitonin – decrease blood calcium Parathyroid Blood Calcium Level Parathyroid Hormone – Increases blood calcium Adrenal Gland Adrenal Cortex Blood Pressure/ Blood Volume Aldosterone – Increase of Sodium and H2O Cortisol – Anti-inflammatory Adrenal Medulla Brain Epinephrine & Norepinephrine – fight or flight Pinal Gland Serotonin Melatonin – contributes to the setting of the bodies biological clock Pituitary Gland – is a pea shaped structure that attaches to the hypothalamus by a stalk called the infundibulum and has 2 separate portions the anterior pituitary and the posterior pituitary. Growth Hormone – promotes growth of body tissues and regulates certain aspects of metabolism Thyroid-stimulating hormone (TSH) – stimulates synthesis and secretion of thyroid hormones by thyroid gland Follicle-stimulating Hormone (FSH) – in females, initiates development of oocytes and induces ovarian secretion of estrogens. In males, stimulates testes to produce sperm Luteinizing Hormone (LH)- In females, stimulates secretion of estrogens and progesterone, ovulation, and formation of corpus luteum. In males, stimulates testes to produce testosterone Prolactin (PRL) – together with other hormones promotes milk production by mammary glands Adrenocorticotropic Hormone (ACTH) – Stimulates secretion of glucocorticoids by adrenal cortex Melanocyte-Stimulating Hormone (MSH) – Exact role in humans in unknown but many influence brain activity; when present in excess can cause darkening of skin Oxytocin (OT)- Stimulates contraction of smooth muscle cells of uterus during childbirth; stimulates contraction of myoepithelial cells in mammary glands to cause milk ejection Antidiuretic Hormone (ADH) – Conserves body water by decreasing urine volume; decreases water loss through perspiration ; raises blood pressure by constricting arterioles Thyroid Gland – butterfly shaped located inferior to the larynx and is composed of right and left lateral lobes T3 (triiodothyronine) and T4 (thyroxine) or thyroid hormones – increase basal metabolic rate; stimulate synthesis of proteins; increase use of glucose and fatty acids for ATP production; increase lipolysis; enhance cholesterol excretion; accelerate body growth; contribute to development of nervous system Parathyroid Glands – on the posterior surface of the lateral lobes of the thyroid gland are small round masses of tissue called parathyroid glands one superior and one inferior are attached to each lateral lobe Parathyroid Hormone (PTH)- Increases calcium (Ca2+ ) and Magnesium (Mg2+) levels and decreases blood phosphate (HPO42-) level; increases bone resorption by osteoclasts; increases Ca2+ reabsorption and phosphate excretion by kidneys; promotes formation of calcitriol which increases rate of dietary Ca2+ and Mg2+ absorption Adrenal Glands- lie superior to each kidney in the retroperitoneal space and have a flattened pyramid shape Mineralocorticoids – increase blood levels of Na+ and water; decrease blood level of K+ Glucocorticoids – Increase protein breakdown, stimulate gluconeogenesis and lipolysis, provide resistance to stress, dampen inflammation, depress immune responses Androgens – Assist in early growth of axillary and pubic hair in both sexes; in females, contribute to libido and are source of estrogens after menopause Epinephrine and Norepinephrine – enhance effects of sympathetic division of autonomic nervous system (ANS) during stress Pancreas – a flattened organ, located in the curve of the duodenum, this first part of the small intestine and consists of a head, body, and tail Glucagon – raises blood glucose level by accelerating breakdown of glycogen into glucose in liver, converting other nutrients into glucose in liver and releasing glucose into blood Insulin – Lowers blood glucose level by accelerating transport of glucose into cells, converting glucose into glycogen and decreasing glycogenolysis and gluconeogenesis; increases lipogenesis and stimulates protein synthesis Somatostatin – inhibits secretion of insulin and glucagon; slows absorption of nutrients from GI tract Pancreatic Polypeptide – Inhibits somatostatin secretion, gallbladder contraction and secretion of pancreatic digestive enzymes Pineal Gland – attached to the roof of the third ventricle of the brain at the midline Melatonin – contributes to the setting of the body’s biological clock; promotes sleepiness Thymus – is located behind the sternum between the lungs Thymosin, Thymic Humoral Factor (THF), Thymic Factor (TF), Thymopoietin – promote the maturation of T cells and retard the aging process 11. Draw a sarcomere and describe the role of all major proteins that were discussed class. T tubules – are invaginations of the sarcolemma into the center of the cell filled with extracellular fluid that carry muscle action potentials down into cell Myofilaments – thick and thin filaments, are contractile proteins of muscle Sarcoplasmic Reticulum (SR) – stores Ca+2 in a relaxed muscle , release of Ca+2 triggers muscle contraction Thick and thin filaments- overlap each other in a pattern that create striations (light I bands and dark A bands), I band only contains thin filaments, arranged in compartments calls sarcomeres separated by Z discs Supporting proteins – M line, titin, and Z disc help anchor the thick and thin filaments in place 12. List all cranial nerves including their makeup (mixed, efferent, afferent), effector/sensory targets and major consequences of damage to these nerves. (Page 508) Olfactory – CN1; Sensory; smell; Afferent Optic – CN2; Sensory; sight; Afferent Oculomotor – CN3; Motor; movement of eyeball, upperlids, constriction of pupils; Efferent Trochlear- CN4; Motor; Movement of eyeball; Efferent Trigeminal – CN5; Mixed(Both); sensory- somatic senses (touch, pain, etc.);Motor- chewing, middle ear muscles; Efferent and Afferent Abducens – CN6; Motor; movement of eyeball; Efferent Facial – CN7; Mixed(Both); Sensory- taste anterior 2/3 tongue, somatic sensory from skin; Motor- facial expression, secretion of tears & salvia; Afferent & Efferent Vestibulocochlear- CN8; Sensory; hearing & equilibrium; Afferent Glossopharyngeal- CN9;Mixed(Both); sensory- taste posterior 1/3 of tongue, somatic senses, monitor BP; Motor- swallowing, secretion of saliva; Afferent & Efferent Vagus – CN10; Mixed(Both); Sensory- taste, monitor BP, Somatic senses of ear; Motor- Parasympathetic(rest & digest), swallowing, vocalization, coughing, GI organ motility; Afferent & Efferent Accessory – CN11; Motor; movement of head& pectoral girdle; Efferent Hypoglossal- CN12; Motor; speak, swallowing, chewing; Efferent 13. Describe sensation and signal transduction for each of the special senses. Olfactory- your ability to smell comes from specialized sensory cells called olfactory sensory neurons which are found in small patch of tissue high inside the nose. Each olfactory neuron has one odor receptor once the neurons detect the molecules, they send messages to your brain which identifies the smell extending from the dendrite of an olfactory receptor cell are several olfactory cilia, which are sites of olfactory transduction. Within the plasma membrane of the olfactory cilia are olfactory receptor proteins that detect inhaled chemicals. Chemicals bind to and stimulate the olfactory receptors in the olfactory cilia. Olfactory receptor cells respond to the chemical stimulation of an odorant molecule by producing a receptor potential, initiating the olfactory response Gustation – taste is the sensation produced when a substance in the mouth reacts chemically with taste receptor cells located on taste buds in the oral cavity Hearing – is the ability to perceive sounds by detecting vibrations, changes in the pressure of the surrounding medium though time, Vision- is the act of seeing, it allows us to see potentially dangerous objects in our surroundings 14. Describe the different kinds of diabetes and how they interact with/are dependent on the endocrine system (Page 663) Because insulin is unavailable to aid transport of glucose into body cells, blood glucose level is high and glucose “spills” into the urine (glucosuria). Type 1 diabetes, previously known as insulin-dependent diabetes mellitus (IDDM), occurs because the person’s immune system destroys the pancreatic beta cells. Type 2 diabetes, formerly known as non-insulin-dependent diabetes