Sheep Brain Dorsal View Labeling Activity

The sheep brain is a frequent subject in anatomical studies because its basic structure shares many similarities with the human brain. Examining the dorsal, or top-down, view provides a clear perspective of its major components. This orientation is fundamental for identifying the primary regions and surface features before exploring the organ’s more complex internal structures.

Major Structures of the Cerebrum

From a dorsal perspective, the most dominant feature is the cerebrum, which is responsible for higher-order functions. It is divided into two large cerebral hemispheres, separated by a deep groove called the longitudinal fissure. This division is a defining characteristic of the brain’s symmetry.

The surface of each cerebral hemisphere is not smooth; it is covered with a pattern of folds. The ridges are known as gyri, while the grooves that separate them are called sulci. This extensive folding increases the total surface area of the cerebrum. This increased area allows for a greater number of neurons, which enhances the brain’s processing capacity.

Lobes of the Sheep Brain

Each cerebral hemisphere is organized into functional areas called lobes. The frontal lobe is at the anterior (front) of the cerebrum and is associated with motor function and planning. Posterior to it is the parietal lobe, which processes sensory information from the body, such as touch and temperature. The ansate sulcus is the feature that separates the frontal lobe from the parietal lobe.

The occipital lobe is located at the posterior (back) of the cerebrum. Its function is to receive and interpret visual information. While mostly observed from a lateral view, the temporal lobes are situated on the sides of the brain, beneath the parietal lobes, and are involved with hearing and memory. The sulci dividing these lobes are less distinct in a sheep brain compared to the demarcated regions in human brain diagrams.

The Cerebellum

Located posterior to the cerebrum and just below the occipital lobes is the cerebellum, which translates to “little brain.” It has a cauliflower-like appearance due to tightly packed folds called folia. These folds, similar to the gyri of the cerebrum, serve to increase the surface area of the cerebellar cortex.

The cerebellum’s role is to fine-tune motor activity. It coordinates voluntary movements, maintaining posture, and balance. Information from sensory systems, the spinal cord, and other parts of the brain are integrated here to produce smooth movements. The cerebellum consists of two hemispheres connected by a central area known as the vermis.