Nokea
In Drosophila, the neuroectoderm is located ventrally during gastrulation, while in mice or frogs, the neuroectoderm is located dorsally. Which statement best describes how the two systems are similar or different?
- A. There are no similarities between flies and vertebrates in development of the nervous system.
- B. Although gastrulation is completely different in invertebrates and vertebrates, the formation of a neural tube is identical in the two types of animals.
- C. There is little similarity, since the neuroectoderm of invertebrates forms their nervous system with no further morphological changes, while in vertebrates, the neural tube forms a bundle of neurons running along the antero-posterior axis called the spinal cord.
- D. Although the invertebrate nervous system is a ventrally located nerve cord, and the vertebrate spinal cord is located dorsally, homologous genes play a role, and neurons are ultimately specified through a process of lateral inhibition in both cases.
Correct Answer: D
Rationale: Despite differences in the location of the neuroectoderm (ventral in Drosophila, dorsal in vertebrates), both systems share similarities in the genetic mechanisms underlying neural development. Homologous genes, such as those involved in lateral inhibition, play crucial roles in specifying neurons in both invertebrates and vertebrates. This highlights the evolutionary conservation of developmental processes despite morphological differences.
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Bradycardia can occur in response to:
- A. elevated intraocular pressure
- B. ocular massage
- C. pulling of the extraocular muscle
- D. all above
Correct Answer: D
Rationale: Bradycardia can be triggered by elevated intraocular pressure, ocular massage, or extraocular muscle manipulation due to the oculocardiac reflex.
The foremost observation to make when providing care to a patient in status epilepticus is
- A. hydration
- B. patency of airway
- C. temperature elevation
- D. response to environmental stimuli
Correct Answer: B
Rationale: Maintaining airway patency is critical in status epilepticus to ensure adequate oxygenation.
The ________ is to feeling fear as the ________ is to feeling pleasure.
- A. pons/medulla
- B. amygdala/hypothalamus
- C. thalamus/hypothalamus
- D. cerebellum/amygdala
Correct Answer: B
Rationale: The amygdala is a brain structure responsible for processing fear and emotional responses, while the hypothalamus is involved in regulating pleasure and reward. The amygdala detects threats and triggers fear responses, such as the fight-or-flight reaction. In contrast, the hypothalamus plays a role in reward pathways and the release of dopamine, which is associated with feelings of pleasure and satisfaction. These structures illustrate the brain's specialization in processing different emotions.
KL is a 34-year-old male admitted to the hospital (large trauma center) after suffering a traumatic brain injury (TBI) secondary to a serious motor vehicle accident. He was in excellent health prior to the accident. HT: 6'2" WT: 190 pounds (86 kg) What is likely the best way to feed KL while he is in the hospital?
- A. nasogastric tube
- B. nasoenteric tube
- C. parenteral nutrients
- D. baby food orally
Correct Answer: B
Rationale: A nasoenteric tube is often the preferred method for feeding patients with traumatic brain injury (TBI) who cannot safely swallow. It allows for enteral nutrition delivery directly into the small intestine, reducing the risk of aspiration compared to a nasogastric tube.
An axon conducts nerve impulses _________ the cell body.
- A. away from
- B. toward
- C. both toward and away from
- D. around, bypassing
Correct Answer: A
Rationale: The axon is a long, slender projection of a neuron that conducts nerve impulses away from the cell body to other neurons, muscles, or glands. When an action potential is generated in the cell body, it travels along the axon to the axon terminals, where neurotransmitters are released into the synapse. This unidirectional flow ensures that signals are transmitted efficiently and accurately to their intended targets.