MCAT Biology : Systems Biology and Tissue Types
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Example Questions
Example Question #2 : Brain And Central Nervous System
A lesion to which brain region would result in a lack of coordinated movement?
The cerebellum
The hypothalamus
The left temporal lobe
The medulla oblongata
The cerebellum
The cerebellum is responsible for the coordination of movement between the motor and sensory cortices. It helps account for movements and correct the magnitude of stimulation of skeletal muscle. The cerebellum is essential for fine-tuning functions like balance and hand-eye coordination.
The medulla, or medulla oblongata, is mainly responsible for the modulation of involuntary vital functions like ventilation rate and heart rate. The hypothalamus plays a key role in the activation of the sympathetic nervous system and also plays a key role in hunger, sexual reproduction, and endocrine function. The temporal lobe is a region of the cerebrum, and is associated with auditory and speech function as well as memory formation.
Example Question #173 : Mcat Biological Sciences
Which section of the brain is responsible for regulating temperature?
Frontal cortex
Medulla
Hypothalamus
Limbic system
Cerebrum
Hypothalamus
Receptors in the hypothalamus regulate temperature by sending nerve signals to muscles and sweat glands in the body. The hypothalamus is located deep within the center of the brain, at the very top of the brain stem. The other answers are different sections of the brain responsible for other tasks. For instance, the cerebrum is the largest section of the brain responsible for memory, consciousness, language and intellect.
Example Question #151 : Biology
Which of the following is part of the hindbrain?
Hypothalamus
Cerebrum
Thalamus
Cerebellum
Broca's area
Cerebellum
The hindbrain consists of the pons, medulla oblongata, and cerebellum.
The cerebrum, thalamus, and hypothalamus are part of the forebrain. Broca's area is a specific region of the cerebrum dedicated to understanding language.
Example Question #3 : Brain And Central Nervous System
Which of the following accurately describes white matter?
White matter is located in the central part of the spinal cord and is surrounded by gray matter
White matter is denser than gray matter
White matter consists of myelinated axons in the central nervous system
White matter is only found in the peripheral nervous system
White matter features the cell bodies of the neurons in the spinal cord
White matter consists of myelinated axons in the central nervous system
White matter refers to the white-colored myelin that surrounds the axons of neurons in the central nervous system. These axons are grouped together, creating distinct regions of white matter. In contrast, grey matter refers to the cell bodies of neurons in the central nervous system. The cell bodies are packed together into dense regions to create grey matter.
In a cross-section of the spinal cord, gray matter is located in the center and is surrounded by white matter.
Example Question #174 : Mcat Biological Sciences
Which is the correct order of sequences during the knee-jerk reflex?
Patella tendon stretches – motor neuron – spinal cord – sensory neuron – quadriceps contract
Quadriceps stretch – sensory neuron – spinal cord – motor neuron – patella tendon contracts
Patella tendon stretches – sensory neuron – spinal cord – motor neuron – quadriceps contract
Patella tendon stretches – spinal cord – sensory neuron – motor neuron – quadriceps contract
Patella tendon stretches – sensory neuron – spinal cord –brain – motor neuron – quadriceps contract (reflex bypasses the brain)
Patella tendon stretches – sensory neuron – spinal cord – motor neuron – quadriceps contract
During the knee-jerk reflex, the neural signal is initiated by the stretching of the patella tendon, which is transmitted via sensory neuron to the spinal cord. In turn, the signal is transmitted to the motor neuron, resulting in the contraction of quadriceps. Most importantly, the reflex bypasses the brain, allowing a speedy reaction of the body to the stimulus.
Example Question #141 : Systems Biology And Tissue Types
A patient who is unable to modulate his own ventilation and heart rate may be suffering damage to which part of his brain?
Corpus callosum
Midbrain
Medulla oblongata
Temporal lobes
Cerebellum
Medulla oblongata
The medulla oblongata, a part of the hindbrain, is primarily responsible for the control of ventilation and heart rate. The midbrain serves as a relay station for visual and auditory information. The cerebellum is responsible for balance and coordination. The corpus callosum is a connective tissue between the two hemispheres of the brain and allows for their intercommunication. The temporal lobes are primarily responsible for auditory processing. Therefore, the patient is most likely suffering from a damage to the medulla oblongata.
Example Question #142 : Systems Biology And Tissue Types
The brain is a very delicate structure with little room to move around. Surrounding the brain and the spinal cord are three protective layers in addition to the skull and the vertebral column. Directly surrounding the brain and spinal cord is the pia mater. Following the pia mater is the arachnoid mater. Between the pia mater and the arachnoid mater is the sub-arachnoid space where the cerebrospinal fluid circulates. Finally, the protective layer is the dura mater is loosely attached to the arachnoid mater but is strongly associated with the skull bone.
Depending on the type of injury, a certain type of vein and/or artery are more susceptible to injury. For example, the meningeal artery and vein run through the foramen spinosum and travel between the two layers making up the dura mater. As the artery and the vein are traveling in between the dura mater, there is a vulnerable region at the temple. A strike to the temple region could rupture these vessels and result in a epidural hematoma.
Traveling from the cerebral cortex to the venous dural sinus (located at certain regions between the two layers of the dura mater) is the cerebral vein. When an injury results in the dura mater shifting away from the arachnoid mater, the cerebral vein could rupture and lead to a subdural hematoma.
When a physician performs a lumbar puncture, he/she is extracting cerebrospinal fluid. Through which of the follow structure(s) must the needle pass?
I. Dura mater
II. Arachnoid mater
III. Pia mater
II only
I and II
I only
I, II, and III
III only
I and II
As described in the passage, the innermost layer is the pia mater, then the arachnoid space, arachnoid mater and finally the dura mater. The dura mater is the outermost layer prior to the skull/vertebral column. Therefore, during a lumbar puncture, the needle will have to pass through the dura mater first then through the arachnoid mater to get to the sub-arachnoid space.
Example Question #13 : Brain And Central Nervous System
The central nervous system consists of the brain and the spinal cord. In general, tracts allow for the brain to communicate up and down with the spinal cord. The commissures allow for the two hemispheres of the brain to communicate with each other. One of the most important commissures is the corpus callosum. The association fibers allow for the anterior regions of the brain to communicate with the posterior regions. One of the evolved routes from the spinal cord to the brain is via the dorsal column pathway. This route allows for fine touch, vibration, proprioception and 2 points discrimination. This pathway is much faster than the pain route. From the lower limbs, the signal ascends to the brain via a region called the gracile fasciculus. From the upper limbs, the signal ascends via the cuneate fasciculus region in the spinal cord.
Patient A has a tumor in his spinal cord. He is able to feel fine touch below the waist. Above the waist, he is unable to feel fine touch on either side. Where is the tumor most likely located?
I. All levels of the spinal cord
II. In the gracile fasciculus region
III. In the cuneate fasciculus region
II only
None of these
I only
III only
I and II
III only
Patient A is unable to feel fine touch above the waist. A tumor in the cuneate fasciculus region will prevent the signal to travel from above the waist to reach the brain.
Example Question #143 : Systems Biology And Tissue Types
The central nervous system consists of the brain and the spinal cord. In general, tracts allow for the brain to communicate up and down with the spinal cord. The commissures allow for the two hemispheres of the brain to communicate with each other. One of the most important commissures is the corpus callosum. The association fibers allow for the anterior regions of the brain to communicate with the posterior regions. One of the evolved routes from the spinal cord to the brain is via the dorsal column pathway. This route allows for fine touch, vibration, proprioception and 2 points discrimination. This pathway is much faster than the pain route. From the lower limbs, the signal ascends to the brain via a region called the gracile fasciculus. From the upper limbs, the signal ascends via the cuneate fasciculus region in the spinal cord.
Which of the following sentences correctly explains what happens when a person steps on a pin?
I. Transmit to the brain rapidly
II. Will utilize the gracile fasciculus region in the spinal cord
III. Will utilize the cuneate fasciculus region in the spinal cord
None of these
III only
I only
II and III
II only
None of these
Fine touch, vibration, proprioception and 2 points discrimination all utilizes the dorsal column pathway. The upper region utilizes the cuneate fasciculus in the spinal cord while the lower region depends on the gracile fasciculus. According to the passage, these sensations are of the rapid pathway whereas other sensations such as pain is not as fast. The dorsal column pathway is heavily myelinated while the pain pathway is not as myelinated.
Example Question #81 : Nervous System And Nervous Tissue
The central nervous system consists of the brain and the spinal cord. In general, tracts allow for the brain to communicate up and down with the spinal cord. The commissures allow for the two hemispheres of the brain to communicate with each other. One of the most important commissures is the corpus callosum. The association fibers allow for the anterior regions of the brain to communicate with the posterior regions. One of the evolved routes from the spinal cord to the brain is via the dorsal column pathway. This route allows for fine touch, vibration, proprioception and 2 points discrimination. This pathway is much faster than the pain route. From the lower limbs, the signal ascends to the brain via a region called the gracile fasciculus. From the upper limbs, the signal ascends via the cuneate fasciculus region in the spinal cord.
Patient A has a tumor in his spinal cord. He is able to feel fine touch above the waist. Below the waist he is unable to feel fine touch on either side. Where is the tumor most likely located?
I. All levels of the spinal cord
II. In the gracile fasciculus region
III. In the cuneate fasciculus region
II only
I only
I and II
None of these
III only
II only
Patient A is unable to feel fine touch below the waist. A tumor in the gracile fasciculus region will prevent the signal from below the waist to reach the brain.
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