Week 1 & 2 Quiz PDF

## Why do hydrogen and potassium readily interact with other atoms? - **Correct Answer:** They both have one electron in their outer shells. - **Incorrect Answer:** They only have electrons in the first shell. - **Incorrect Answer:** They have electrons in all shells. - **Incorrect Answer:** The...

## Why do hydrogen and potassium readily interact with other atoms? - **Correct Answer:** They both have one electron in their outer shells. - **Incorrect Answer:** They only have electrons in the first shell. - **Incorrect Answer:** They have electrons in all shells. - **Incorrect Answer:** They both have four electrons in the outer shell. Both hydrogen and potassium have one electron in their outer shells, meaning they can readily interact with other atoms. ## Which of the following is true regarding the role of bicarbonate in maintaining homeostasis? - **Correct Answer:** Bicarbonate functions as a buffer to neutralize acids. - **Incorrect Answer:** Bicarbonate dissociates from hydroxide to form a free hydroxide that neutralizes acid. - **Incorrect Answer:** Bicarbonate releases protons when diluted with water, which neutralizes acids. - **Incorrect Answer:** Bicarbonate is partially ionized in water and is considered to be a weak base. Bicarbonate is produced in the pancreas for the purpose of neutralizing the acidity in chyme as it moves from the stomach to the small intestine. It also plays a major role in the carbonic acid buffer system. ## Which of the following correctly describes the bond between two oxygen atoms? - **Correct Answer:** Two oxygen atoms share a double bond, enabling them both to fulfill the octet rule. - **Incorrect Answer:** Two oxygen atoms share bonds with two hydrogen atoms, enabling them to fulfill the octet rule. - **Incorrect Answer:** Two oxygen atoms share protons, forming a double bond and fulfilling the octet rule. - **Incorrect Answer:** Two oxygen atoms share two electrons to form a double bond and eight neutrons to fulfill the octet rule. One oxygen atom will share two of its electrons with the other atom, forming a double bond and fulfilling the octet rule for both atoms. ## What is the source of familial forms of hypercholesterolemia? - **Correct Answer:** Mutations in the gene that codes for apolipoprotein B-100 (Apo B-100). - **Incorrect Answer:** Mutations in the gene that codes for very low-density lipoproteins. - **Incorrect Answer:** Increased intake of saturated fatty acids. - **Incorrect Answer:** Environmental factors that cause mutations of the genes that code for triglycerides. Familial forms of hypercholesterolemia are usually associated with mutations in the gene that codes for Apo B-100. ## Which of the following correctly describes the process of sodium chloride dissolving in water? - **Correct Answer:** The sodium ion acquires a hydration shell of water molecules, with the oxygens oriented toward the sodium ion; the chloride ion acquires a hydration shell of water molecules, with the hydrogens oriented toward the chloride ion. - **Incorrect Answer:** The atoms of sodium and chloride remain attached via an ionic bond. - **Incorrect Answer:** The sodium and chloride atoms separate, retaining their initial atomic valence shell electron configuration. - **Incorrect Answer:** The sodium ion acquires a hydration shell of water molecules, with the hydrogens oriented toward the sodium ion; the chloride ion acquires a hydration shell of water molecules, with the oxygens oriented toward the chloride ion. The electronegative oxygen within polar water molecules is attracted to the sodium's positive charge; the electropositive hydrogens within water molecules are attracted to the chloride's negative charge. ## Which category of biomolecules has the greatest hydrophobicity? - **Correct Answer:** Lipids - **Incorrect Answer:** Amino acids - **Incorrect Answer:** Carbohydrates - **Incorrect Answer:** Nucleotides Fatty acids, triglycerides, and cholesterol are rich in C-H bonds and are very nonpolar and hydrophobic. ## Which of the following food products contain the least amount of water? - **Correct Answer:** Oil - **Incorrect Answer:** Almonds - **Incorrect Answer:** Dried mushrooms - **Incorrect Answer:** Salami Water content in extra virgin olive oil is about 700 to 2,000 ppm, which is significantly lower than the water content in other foods simply because it is hydrophobic. ## The process of apoptosis is associated with: - **Correct Answer:** Cell shrinking and nuclear fragmentation. - **Incorrect Answer:** Cell membrane rupture and leakage of cell contents. - **Incorrect Answer:** Pathological damage and injury to tissue. - **Incorrect Answer:** Acute tissue inflammation. In apoptosis, cells get smaller and the nucleic acids are reduced to fragments and packaged. ## Which of the following distinguishes apoptosis from necrosis? - **Correct Answer:** Stepwise activation of a death program. - **Incorrect Answer:** Initiation by trauma and other cell-damaging insults. - **Incorrect Answer:** Degradation of DNA. - **Incorrect Answer:** Activation of intracellular enzymes. Apoptosis, also known as “programmed cell death," follows a specific sequence of steps and clears cells without significant tissue disruption and inflammation. ## A biochemical marker of inflammation that often correlates with frailty is: - **Correct Answer:** Increased tumor necrosis factor-alpha levels. - **Incorrect Answer:** Increased estrogen levels. - **Incorrect Answer:** Increased growth hormone levels. - **Incorrect Answer:** Increased vitamin D levels. Increased levels of the inflammatory cytokine tumor necrosis factor-alpha correlate with frailty. ## A client presents with hallucinations and mania. A first-generation antipsychotic is prescribed to block specific receptors. Which of the following catecholamines is the drug most likely blocking? - **Correct Answer:** Dopamine. - **Incorrect Answer:** Acetylcholine - **Incorrect Answer:** Norepinephrine - **Incorrect Answer:** Serotonin Antipsychotics generally block D2 receptors, inhibiting the action of dopamine. ## Which of the following best describes pain as a result of damage to nerve fibers or pathways? - **Correct Answer:** Intermittent electric shock-like jolts. - **Incorrect Answer:** Pain from visceral regions interpreted as somatic pain. - **Incorrect Answer:** A stimulus that would normally be only slightly painful is perceived as extremely painful. - **Incorrect Answer:** An increase in stimulation of low-threshold mechanoreceptors results in a decreased perception of pain. Neuropathic pain is described as a persistent burning sensation with periods of shooting, stabbing, or electric shock-like jolts of pain. ## Which of the following is most likely to be observed after a stroke of the motor cortex? - **Correct Answer:** Weakness and lack of coordination of the contralateral hand. - **Incorrect Answer:** Absent muscle stretch reflexes. - **Incorrect Answer:** Impaired rapidly alternating movements. - **Incorrect Answer:** Resting tremor. The corticospinal tract is the major influence on voluntary movement, such as skilled movements of the hands. ## Which of the following correctly describes the process of making smooth, precise movements? - **Correct Answer:** The cerebellum monitors movements in progress and modifies motor signals, as needed, to ensure movements are smooth and precise. - **Incorrect Answer:** Local circuits generate repetitive, patterned movements with no additional input. - **Incorrect Answer:** Muscle spindles provide feedback on correct movement execution. - **Incorrect Answer:** Brainstem pathways promote unconscious adjustment of muscle activity for corrections of quality and precision. The cerebellum modifies signals as needed to create smooth and precise movements. ## Which of the following correctly describes the pathophysiology of myasthenia gravis? - **Correct Answer:** Autoantibodies are formed to nicotinic acetylcholine receptors, resulting in degeneration of the neuromuscular junction. - **Incorrect Answer:** Antibodies attack the myelin sheath of nerve fibers, causing inflammation and degradation. - **Incorrect Answer:** Antibodies attack and destroy spinal motor neurons, impeding neuromuscular transmission. - **Incorrect Answer:** Antibodies to acetylcholinesterase reduce synaptic degradation of acetylcholine. Myasthenia gravis is an autoimmune disorder where antibodies attack the nicotinic acetylcholine receptors. The result is inflammation that causes degeneration of the neuromuscular junction and failure of neuromuscular transmission. ## Which of the following correctly characterizes a lower motor neuron lesion? - **Correct Answer:** Hypotonia. - **Incorrect Answer:** Dysmetria. - **Incorrect Answer:** Hyperreflexia. - **Incorrect Answer:** Broad-based gait. Lower motor neuron lesions cause weakness and hypotonia of the affected muscles. ## Which basal ganglia neurotransmitter must be present at correct levels relative to dopamine for normal motor function? - **Correct Answer:** Acetylcholine. - **Incorrect Answer:** Glutamate. - **Incorrect Answer:** Norepinephrine. - **Incorrect Answer:** Serotonin. Normal motor function requires a balance of basal ganglia dopamine and acetylcholine. As dopamine becomes depleted in Parkinson disease, some improvement can be achieved by inhibiting acetylcholine transmission, in addition to the initial management strategies that increase dopamine transmission. ## Which motor manifestations are expected following a major middle cerebral artery stroke that affects the left hemisphere lateral motor cortex? - **Correct Answer:** Weakness and lack of movement of the right face and arm, exaggerated muscle stretch reflexes. - **Incorrect Answer:** Paralysis and absent muscle stretch reflexes of left face and arm. - **Incorrect Answer:** Rigidity with tremor of left face and arm, normal muscle stretch reflexes. - **Incorrect Answer:** Absence of movement and muscle atrophy with absent muscle stretch reflexes. Damage to the left hemisphere motor cortex lateral surface will impact movement of the right arm and face, causing weakness, lack of coordinated purposeful movements, and hyperactive stretch reflexes. ## A clinician asks a client to close their eyes and then touches the right forearm with the tip of a cotton applicator. The client indicates a dull sensation on the right forearm. What does this indicate? - **Correct Answer:** Ability to correctly discriminate the location of sensory stimulus by the dorsal column/medial lemniscus system. - **Incorrect Answer:** Inability to discriminate the quality of sensory stimulus by thalamic neurons. - **Incorrect Answer:** Ability to detect vibration by the sensory cortex. - **Incorrect Answer:** Ability to correctly discriminate the quality and location of sensory stimulus by the spinothalamic system. The dorsal column/medial lemniscus system relays light touch, vibration, and position to the thalamus, and the sensory cortex thalamic neurons detect the quality and location of a sensory stimulus; the client has correctly identified both.