Biological Issues Quiz - Assignment Example

Multiple Choice Quiz Name Course Institutional affiliation Question Set 1 (1) What function do cranial nerves perform? There are 12 different types of cranial nerves; they are found in pairs at the bottom part of the brain. Every cranial nerve pair controls specific functions of the human body. Their functions vary, but the main functions include helping the brain interpret the five senses, muscle control and controlling glands in the human body. Olfactory nerve- helps in the brain to interpret the sense of smell. Optic nerve function –it improves the vision of an individual. If this nerve is damaged, it can result in blindness. Oculomotor nerve -it controls pupils’ condition and eye movement. This nerve permits us to shift eyes in reaction to stimuli and widen or tighten our pupils in reaction to varying light conditions. Trigeminal nerve – it controls the muscles responsible for chewing in the mouth. It also gives the head and face the sense of pain. Abducens nerve- they help the eyes from being at a distance of facial midline. This nerve works alongside the cranial nerves III and IV to ensure the individual has the best vision. However, if these nerves do not work together, they result in double vision. Facial nerve - they control the face physique which is in control of expressions of the face such ability to smile or frown. They also help in the production of taste in two-thirds of the tongue as well as, give the ear the sensation of touch. Vestibulocochlear nerve-this nerve is divided into two: the acoustic and vestibular divisions. The two are responsible for ensuring an individual has proper hearing and for the purpose of establishing normal balance respectively. Gloss pharyngeal nerve- it promotes taste on the back part of the tongue, moreover, it is sensitive to pain and touch in the tongue as well as promote swallowing of food. The vagus nerve controls the sensory and motor role of glands and the heart. In addition to this, they aid in the process of digestion. Spinal accessory nerve helps both the trapezius muscle and sternocleidomastoid muscle to control the head movements. The hypoglossal nerve aids in the movement of the tongue. (2) Find out the sections of the brain that is concerned with: Anger Medulla Oblongata Breathing Medulla oblongata Consciousness cerebrum Coordination cerebellum Disgust hypothalamus Fight or Flight hypothalamus Happiness Limbic system Hearing cerebrum Language understanding left temporal lobe (Wernicke's Area) Long term episodic memory hippocampus Movement The ascending frontal gyrus and the parietal lobe Sadness Medulla oblongata Self-awareness Insular cortex Self-control dorsal fronto-median cortex Smell Frontal Lobe Speech production Broca's area of the temporal lobe Taste cerebellum, or the forebrain Thirst and hunger hypothalamus Touch hypothalamus Vision Visual Cortex, occipital lobe and the Optic Pathways (3) What are the four lobes of the brain called? a) The frontal lobe- it is located at the front part of the brain. b) The parietal lobe- it is located in the middle section of the brain. c) The temporal lobe- it is located on the bottom section of the brain. d) The occipital lobe- it is situated at the rear portion of the brain (4) What are two functions of the limbic system? a) Regulates the breathing and other vital life functions b) Maintaining the heart beat of an individual. (5) Name five functions controlled by the brain stem. a) The respiratory control centre b) The cranial nerves c) The vasomotor centre d) The cardiac system e) Regulating the blood pressure Question Set 2 (1) What is the function of the premotor cortex? Its referred to as a lateral and medial mechanism within the given location. 65% neurons within it are connected to a given time to the experiencing of the actions. This is mainly in the primary motor area. It is important to note that these cells are engaging in the movements towards a given direction. (2) What is the function of the supplementary motor area? The Supplementary motor area is used to plan motor actions and bimanual control. The supplementary motor area mainly manages actions that are under internal control. An example of such is the performance of a series of movements from memory as opposed to movements directed by a visual signal. (3) What is the main pathway for the control of voluntary movements in humans? The corticospinal zone is the chief alleyway for control of voluntary movement in humans. (5) What is a muscle cell (motor unit) made of? Muscle is mainly composed of muscle cells. Inside the cells there are myofibrils; in the myofibrils they contain sarcomeres, the sarcomeres are composed of actin and myosin. Each muscle fiber is surrounded by endomysium. Muscle fibers are bound together by perimysium into bundles called fascicles; muscle is then formed by bundles grouping together, which end up being enclosed in an epimysium sheath. (6) Where are the stretch receptors found, and what is their function? Stretch receptors are mechanoreceptors in other organs like the bowel wall and muscles. They are linked to the medulla and are usually responsive to the distention of the thorax. A receptor that detects stretching in a muscle. Stretch receptors are essential for the coordination of muscle activity. In addition to this, they help in transmitting information regarding the condition of muscles to the central nervous system. (7) Role of cerebellum The cerebellum is part of the brain that is covered with the cortex. It consists of two parts that are subdivided into lobes. These lobes are then divided by a small wall known as the vermis, or "worm." The frontal lobe is identified as the pale cerebellum; it gets proprioceptive signals from the spinal cord and its main function is to manage the anti-gravity muscles in the body, therefore, controlling the body posture. The posterior lobe, or neocerebellum, is the latest division of the cerebellum. Its function is mainly to coordinate muscles that control movement using the reserve of instinctive locomotion. Inhibitory neurotransmitters, particularly GABA neurotransmitters, are established at this point. This part of the lobe takes up a vital function in fine motor synchronization. The flocculonodular lobe is made up of the flocculi, the majority primeval division of the cerebellum, and the nodulus, the slimmest and lesser fraction of the vermis. This lobe is concerned with the upholding of symmetry. Four diverse nuclei are situated deep inside every cerebellar hemisphere; the dentate nucleus, the emboli form nucleus, the fastigal nucleus, and the globose nucleus. These profound nuclei contain axons that venture to the brain stalk, distributing signals out to be conveyed to other sections of the central nervous system. The deep nuclei are synchronized by radish-shaped cells situated in the cerebellar cortex called Purkinje cells. The Purkinje cells organize the productivity of the cerebellum by restraining the dismissal of the profound nuclei. The Purkinje cells project to the dentate nuclei, even as the in-between cortex synapses among the globose nuclei and the emboli form. The fastigial nuclei obtain input from Purkinje cells found in the cerebellar cortical casing of the vermis. (8) What is the role of the basal nuclei? Even though the function of the basal ganglia in motor control is obvious, moreover there are lots of hints concerned in the organization of actions in an extra primary means, at the point of enthusiasm. In Parkinson's ailment, the capacity to carry out the mechanism of movement is not really exaggerated, but motivational aspects such as starvation fail to cause actions to be started or switched at the correct times. (9) What is the neurotransmitter between motor neurons and muscle fibers? The boundary amid a motor neuron and muscle fiber is a dedicated synapse called the neuromuscular intersection. Upon sufficient stimulation, the motor neuron liberates an overflow of neurotransmitters that connect to postsynaptic receptors and activate a response in the muscle fiber. (10) Which ions enter the muscle fiber to produce contraction? The calcium ions depart the troponin molecule in order to preserve the calcium ion amounts in the sarcoplasm. The vigorous release of calcium ions into the sarcoplasmic reticulum generates a shortage in the liquid around the myofibrils. This results to the elimination of calcium ions from the troponin. Therefore, the tropomyosin-troponin complex yet again covers the binding locations on the actin filaments and contraction ends. Question Set 3 (1) The reasons for the action potential flow one-way and not turn back on itself? There are two reasons. a) Ion selectivity, the electrical basis of voltage-sensitivity. Action potentials usually transmit back into the dendrites because, in general, they do not have a sufficiently high density of voltage-sensitive Na+ channels. Nevertheless, once the action potential reaches the axon terminals it does not go back and maintains its one direction. b) There is a mechanism that closes the permeability pathways. (2) What is the importance of temporal and spatial summation? The significant thing is to permit the stimulation to convey the membrane latent of the axon hillock to verge. When the membrane ability gets to a threshold, an action potential can occur. Every neuron is getting signals from several neurons, and it takes that entire signal and chooses whether or not to initiate an act potential. It essentially unites the signals and produces an Action Potential if the summation of all Potentials is great enough. (3) Which types of synapses are thought to be symmetrical? Asymmetrical? Symmetrical synapses are categories of synapse taking place mainly on dendrite shafts and neuronal cell bodies. Symmetric synapses entail axons restraining clusters of largely compressed or stretched out vesicles and do not have a well-known postsynaptic density. Asymmetrical synapses, on the other hand, are set up on the dendritic spines and shaft. They are also found on cells of bodies. (4) What is Dale’s law? Is it correct? The principle basically states that a neuron performs the same chemical action at all of its synaptic connections to other cells, regardless of the identity of the target cell. However, the possibility has at least some value as a stimulus to further experiment. (5) Axons usually synapse with a dendrite. What is this type of synapse called? What other synaptic connections are possible? (Give two more examples) Axodendritic synapse: in this case, the Axon is connected to another neuron’s dendrites Other examples:  Axosomatic synapse: in this case the Axon is connected directly to another neuron’s soma  In neuromuscular junctions, axons synapse directly connected to the muscles. Ax axonal synapse: in this case the Axon is connected to another neuron’s axon Question Set 4 (1) Funnel web spider venom (Agatoxin) blocks calcium channels. What might the consequence of this be? Blocked calcium channels decrease the force of contraction of the myocardium which are the heart muscles. They block cardiac muscles and blood vessels leading to a decrease in muscle tightening. In the heart, reductions in calcium available for every pulse cause a decline in cardiac contractility. In blood vessels, a reduction in calcium causes fewer contractions of the vascular smooth muscle and so a boost in arterial width thus vasodilatation takes place. This reduces body peripheral resistance. A reduction in cardiac contractility then, reduces cardiac output. For this reason, blood pressure drops. (2) Honey bee venom (Apamin) blocks potassium channels. What might the consequence of this be? The most important responsibility of potassium canals in cardiac act potentials is cell repolarization. Therefore, blocking these channels slows repolarization, which as a result, increases the action potential duration as well as an increase in the effective refractory period (ERP). (3) Blue-ringed octopus venom (Maculotoxin) blocks sodium channels. What might the consequence of this be? The rapid influx of sodium ions results in the polarity of the plasupplementary motor area membrane reversing. Thus, the ion channels inactivate rapidly. When the sodium canals close, sodium ions cannot penetrate the neuron. Thus, they are vigorously taken out of the plasupplementary motor area membrane. As an effect, Potassium canals are triggered, causing an external current of potassium ions. This returns the electrochemical incline to the inactive state. Subsequent to an act potential has taken place, a transient negative shift, called the after hyper polarization or refractory period occurs. This is, due to additional potassium currents in the bloodstream. Through this is the mechanism, the action potential does not reverse (Myers, 2004). (4) What is the relationship between the thickness of a nerve fibre and the speed that an action potential travels down it? Speed of nerve impulses is more rapid in thick nerve fibers than slim nerve fibers since with the raise in thickness of nerve fibres, there is a reduction in resistance of nerve fiber to nerve impulse. (5) Why is the knee jerk reflex so rapid? A Knee jerk is a reflex that is experienced by tapping just beneath the knee causing the lower leg to jolt frontward abruptly. This happens when the patellar tendon is tapped to elicit an involuntary jerk of the leg forward. (6) What is meant by convergence and divergence? Divergence refers to some kind of fluctuation or unrestricted growth whereas convergence describes any limiting behavior, chiefly of an endless sequence or series, toward some limit. Question Set 5 (1) For each of the drugs listed, complete the following table: Effects on the body (stimulant or depressant What neurotransmitter(s) it affects Alcohol Depressant dopamine Amphetamines Stimulant Dopamine, mesolimbic, and mesocortical Barbiturates Depressants dopamine Caffeine Stimulant Dopamine and mesocortical Cocaine Stimulant dopamine Ecstasy Stimulant serotonin Heroin Depressant endogenous opioids LSD hallucinogen dopamine Marijuana Stimulant dopamine Nicotine Stimulant acetylcholine Rohypnol hallucinogen Dopamine and psilocin PCP hallucinogen Psilocin GHB Depressant GABAergic neurons Hallucinogenic mushrooms hallucinogen Psilocin (2) Why do drugs have multiple effects on the body? Drugs, once ingested are transported in the bloodstream up to the CNS. The CNS affects all the body functions. Therefore, this allows the drugs to affect many parts of the human body since they are all relying on the central nervous system. Drugs also work by distorting the way man’s five senses work. (3) What factors are associated with individual differences in drug action? a) Dose and route of administration b) The time c) Individual’s psychological environment d) Metabolism rate e) Excretion route f) Age g) Weight h) Sex and hereditary influences (4) What is the therapeutic ratio? The therapeutic index/therapeutic ratio, is an assessment of the amount of a therapeutic agent that results in the therapeutic result to the quantity that results to death. Quantitatively, it is the relative amount specified by the fatal dosage alienated by the therapeutic dosage. Question Set 6 (1) Name five bodily processes that hormones may affect. a) Homoeostasis b) Digestion c) Circulation d) Gene replication e) Reproduction f) Metabolism (2) Name the eight endocrine glands * Pineal * Islets of Langerhans in the pancreas * Ovaries * Hypothalamus * Adrenal * Parathyroid * Pituitary * Testes * Thyroid (3) What is the name of the stalk connecting the pituitary gland to the hypothalamus? Pituitary stalk (4) Name the two sections of the pituitary gland and the mechanisms that control their activity. Anterior pituitary or Adenohypophysis –Rathke’s Pouch Posterior pituitary or Neurophysis- Oxytocin  Name the hormone corresponding with the following functions: - Promotes protein synthesis.- growth hormones - Controls release of cortisol- The hormone ACTH - Regulates growth, development and function of the sex organs- estrogen and progesterone. They are responsible in assisting the growth and purpose of the sex organs in female. The testosterone, is concerned with the growth and the operations of the male sex organs. (5) Which hormone is likely to be released if you eat a salty meal? Aldosterone (6) Which hormones would be affected by a diet lacking in iodine? Thyroid stimulating hormone (TSH) Question Set 7 (intra-session break) (1) Which hormones are secreted by the adrenal cortex? Cortisol Aldosterone Androgens, (2) Why might masculinisation of women occur after the menopause? During menopause, estrogen levels from the ovaries decrease causing the masculinization effect. This mostly is experienced through the secretion of androgen. (3) Why would a medical professional want to check levels of adrenal medulla hormones in a patient presenting with elevated stress responses? They are secreted in reaction to a stimulation created by sympathetic nerves, particularly during stressful situations. (4) What is the name of the process by which hormone production is down-regulated in response to rising levels in the body? Hormone Biosynthesis. (5) Name four areas of the cortex involved in motor control. a) The primary motor cortex b) The secondary motor cortices, including: the posterior parietal cortex The premotor cortex, and the supplementary motor area (or supplementary motor area). (6) What is the role of the primary motor cortex? The primary motor cortex is in charge of creating the neural impulses scheming effecting of movement. (7) Why is a greater area of the primary motor cortex devoted to certain regions in comparison with others? Stimulation of regions which are in front of the M1 cause more complicated movements; hence, more electrical current is required to initiate movements from these areas than in other areas. (8) What is the function of the posterior parietal cortex? In addition the frontal cortex, the posterior parietal cortex evidently takes up a task in voluntary movements; through evaluating the circumstance in which they are being prepared. The parietal cortex obtains somatosensory, proprioreceptive, and visual signals, and after that it uses them to resolve such things as the locations of the body and the objective in space. It thus makes internal models of the movement to be made, preceding to the participation of the premotor and motor cortices. Inside the posterior parietal cortex, two particular regions are notable. Region 5 obtains information from somato sensory regions 1, 2, and 3 of the cortex. Region 7 additionally incorporates the already extremely integrated signals from the visual regions of the cortex, for example V5 and MT. The parietal lobes are themselves directly connected with the prefrontal areas. Together, these two regions stand for the uppermost point of incorporation in the motor control ladder. It is here that the results are completed about what action to take. The latter parietal and prefrontal regions send their axons to region 6 which, once it has been conversant about the type of act to perform, assists to decide the characteristics of the suitable movement for this idea. Question Set 8 (1) How is the cerebellum involved in coordinated movement? The cerebellum works alongside other parts of the central nervous system to initiate, produce and control movement. This part of the brain is estimated to contain half of the brain’s neurons that are 100 billion. These neurons are mainly involved in cognitive behaviors and motor movement. The output in this part of the brain does not work like others in a pyramid format, but it sends its feedback loops with other systems. The learned skills and movements of any activity undertaken by any person always originate from the cerebellum. (2) Damage to one side of the body affects movement on the __opposite _____ side. (3) Which side of the brain is dominant for spatial abilities, face recognition, visual imagery and music? Right side (4) In an individual whose corpus callosum has been cut, information is presented in the right visual field. Will the person be able to say the name of the object? Yes, this is because with time, the other side of the brain adapts and the individual can be able to understand and name objects. - What would happen if the object is in the left visual field? The individual will be unable to decipher the object. (5) What happens in the Wada test? During the Wada test, the doctor who in this case is the neuroradiologist induces one side of the brain to sleep momentarily. This is done by the use of anesthetic injected into the internal carotid artery. If the doctor injects the right carotid, the right side of the brain sleeps and cannot transmit information to the left side to ensure that the brain is asleep, EEG recordings are done to ascertain that the brain is working well. Once the side of the brain is asleep, the epileptologist takes time to evaluate the person’s ability to speak, identify and remember things. The side of the brain that is awake tries to make out and memorize what it sees. When the anesthetic clears, the side of the brain that was asleep becomes alert. An epileptologist then asks the individual questions to test how much they remember. The responses are recorded. After a short duration, the other side of the brain is put to sleep and a new experiment similar to the first one but with different objects is conducted. The doctors then compare the memory results and language results of each side of the brain to determine which one is best suited for language and memory. Reference Myers, D. G. (2004). Psychology. New York: Worth Publishers, 2004 Read More