Each cerebral hemisphere is divided into how many lobes?

Appeared in: RUHS, Jaipur, PB B.Sc Nursing Entrance-2020

Explanation

The cerebrum, the largest part of the brain, is divided into two cerebral hemispheres (left and right).
Each hemisphere is further subdivided into four primary lobes, which are named for the overlying cranial bones.
The four lobes are the frontal, parietal, temporal, and occipital lobes.
Each lobe has specialized functions, ranging from executive tasks in the frontal lobe to visual processing in the occipital lobe.

Option A: This is incorrect. The brain has two cerebral hemispheres, but the question asks for the number of lobes within each hemisphere.
Option B: This is an incorrect count of the lobes in a cerebral hemisphere.
Option D: This is incorrect in the standard classification. While some neuroanatomists consider the insular cortex a fifth lobe, the four-lobe model is the most common and universally accepted division in nursing and general anatomy.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Anatomy of the cerebral hemispheres as background academic context rather than a clinical decision trigger.
Understanding the functions of each lobe is crucial for nurses to assess neurological deficits. For example, a patient with a stroke affecting the occipital lobe will likely have visual disturbances.
Damage to Broca's area in the frontal lobe can cause expressive aphasia (difficulty speaking), while damage to Wernicke's area in the temporal lobe causes receptive aphasia (difficulty understanding speech).
What if? If a patient presents with sudden personality changes, disinhibition, and poor judgment, the nurse should suspect potential frontal lobe dysfunction and perform a focused neurological assessment, notifying the physician promptly.

How to Approach the Question

First, identify the key terms in the question: 'cerebral hemisphere' and 'lobes'.
This is a factual recall question about basic neuroanatomy.
Recall or visualize the structure of the brain. The cerebrum is the large, wrinkled outer part.
Remember that the cerebrum is split into two hemispheres.
Access your knowledge of how each hemisphere is subdivided. The standard division involves four main parts.
Evaluate the options: '2' is the number of hemispheres, '4' is the standard number of lobes, and '5' is a less common classification. Select the most standard and widely accepted answer.

Concept Tested & Keywords

Qip4BiS6Dlv84-cJved1P2

E6 Medicine Davidson Principles Practice 24e p. 1086-1088

E6 Anatomy Applied Ashalatha 4e p. 411-413

Practise the full RUHS, Jaipur, PB B.Sc Nursing Entrance-2020

Attempt every question from this paper in a timed mock, then review the full solution for each one.