Nokea
What is the relationship between dorso-ventral patterning of the neural tube and patterning of the somites?
- A. The somites pattern the neural tube after they form.
- B. The neural tube plays the role of organizer in being the sole influence on patterning in the somites
- C. Sonic hedgehog from the notochord and floorplate of the neural tube confers ventral fates on both the neural tube and the somite, while BMPs confer more dorsal fates.
- D. Both the neural tube and the somites acquire their dorso-ventral patterning during gastrulation
Correct Answer: C
Rationale: Dorso-ventral patterning of the neural tube and somites is regulated by opposing gradients of Sonic hedgehog (Shh) from the notochord and floorplate (ventralizing signals) and BMPs from the dorsal neural tube (dorsalizing signals). These signals coordinate the development of both structures, ensuring proper alignment and function of the nervous system and musculoskeletal system.
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The patient's spinal cord injury is at T4. What is the highest-level goal of rehabilitation that is realistic for this patient to have?
- A. Indoor mobility in manual wheelchair
- B. Ambulate with crutches and leg braces
- C. Be independent in self-care and wheelchair use
- D. Completely independent ambulation with short leg braces and canes
Correct Answer: C
Rationale: Independence in self-care and wheelchair use is realistic for T4 injuries.
To provide comfort to a client after a lumbar puncture, what step must the nurse take?
- A. Position the client flat for at least three hours or as directed by the physician.
- B. Keep the room well lighted and play some soothing music in the background.
- C. Help the client ambulate and perform a few light leg exercises.
- D. Provide some easy reading material to the client.
Correct Answer: A
Rationale: Flat positioning reduces the risk of post-lumbar puncture headache.
A patient has blindness related to a functional neurological (conversion) disorder but is unconcerned about this problem. Which understanding should guide the nurse's planning for this patient? The patient is:
- A. suppressing accurate feelings regarding the problem.
- B. relieving anxiety through the physical symptom.
- C. meeting needs through hospitalization.
- D. refusing to disclose genuine fears.
Correct Answer: B
Rationale: The correct answer is B because the patient is unconcerned about the blindness, indicating that the symptom is relieving anxiety. This is characteristic of conversion disorder where physical symptoms alleviate psychological distress. Other choices are incorrect because the patient is not necessarily suppressing feelings (A), not meeting needs through hospitalization (C), and not refusing to disclose fears (D).
Structures involved in colour vision include:
- A. parvocellular pathway
- B. superficial layer 4C of visual cortex
- C. superior colliculi
- D. geniculate layers 1-2
Correct Answer: A
Rationale: The parvocellular pathway is primarily responsible for colour vision and high spatial resolution. The superior colliculi and geniculate layers 1-2 are not directly involved in colour processing.
Which of these cells are not a type of neuroglia found in the CNS:
- A. astrocytes
- B. microglia
- C. Schwann cells
- D. ependymal cells
Correct Answer: C
Rationale: Schwann cells are a type of neuroglia found in the peripheral nervous system (PNS), not the central nervous system (CNS). Astrocytes, microglia, ependymal cells, and oligodendrocytes are all types of neuroglia found in the CNS. Thus, C is the correct answer.