Chapter 8 Physiological Psychology Study Quiz

Damage to the cerebellum, which is responsible for coordinating movement and maintaining balance, can lead to jerky, erratic, and uncoordinated movements. This is because the cerebellum plays a crucial role in fine-tuning motor commands and ensuring smooth and coordinated muscle contractions. When it is damaged, the communication between the cerebellum and other parts of the brain and body is disrupted, resulting in difficulties with movement control and coordination.

not-available-via-ai

Flexion muscles are responsible for drawing in a limb, and they do so by contracting. When a flexor muscle contracts, it pulls the limb towards the body, causing it to bend or flex. This action is commonly seen in movements such as bending the elbow or bringing the knee towards the chest. The phrase "draw in a limb" refers to the action of flexion, and "contracting" describes the muscle's movement in this process.

Calcium ions play a major regulatory role in the contraction of both smooth and skeletal muscles. Calcium is released from the sarcoplasmic reticulum in response to an action potential, allowing the myosin and actin filaments to interact and generate force. This interaction is essential for muscle contraction. Additionally, calcium ions also regulate the activity of enzymes involved in muscle contraction and relaxation. Therefore, calcium ions are crucial for the proper functioning of both smooth and skeletal muscles.

Parkinson's Disease is a neurodegenerative disorder characterized by muscle rigidity, resting tremor, and slow movements. It is caused by damage to dopamine neurons in the brain. However, stereotaxic lesions of the globus pallidus, which involve the destruction of a specific brain region, are not a cure for Parkinson's Disease. While this procedure may help alleviate some symptoms, it does not provide a permanent cure for the condition.

The statement "Each muscle has only one motor unit" is not true. A motor unit is a single motor neuron and all the muscle fibers it controls. Each muscle can have multiple motor units, with each motor unit consisting of a motor neuron and the muscle fibers it innervates. This allows for precise control and coordination of muscle contraction.

The correct answer is monosynaptic reflex in which the alpha motor neuron quickly contracts muscle fibers. In this reflex, the sensory neuron directly synapses with the motor neuron in the spinal cord, bypassing the interneuron. This allows for a faster response as there are fewer synapses involved. The alpha motor neuron then signals the muscle fibers to contract, causing the leg to kick out in response to the doctor's stimulus.

The Golgi tendon organ receptors are sensory receptors located in the tendons that connect muscles to bones. These receptors are responsible for detecting changes in muscle tension. When the tension in the muscle exceeds a certain threshold, the Golgi tendon organ receptors send inhibitory signals to the agonist muscle fibers, which are responsible for contracting the muscle. This inhibitory signal prevents the muscle from exerting too much force and potentially causing damage or ripping. Therefore, the activation and inhibition of agonist muscle fibers by Golgi tendon organ receptors help prevent muscle damage and ensure that the body stops trying to lift a fridge before the muscles rip.

Huntington's Disease is a neurodegenerative disorder characterized by uncontrollable jerky movements, caused by the degeneration of the caudate nucleus and putamen. It is also hereditary, meaning it can be passed down from one generation to another. However, it does not involve the loss of cells associated with glutamate.

Sympathetic apraxia causing paralysis of the left arm and hand, but not the right arm and hand, is untrue. Apraxia refers to a neurological condition that affects a person's ability to perform purposeful movements, and it is not related to sympathetic responses. Therefore, it is incorrect to associate apraxia with sympathetic paralysis affecting only one side of the body.

The correct answer is alpha motor neuron axon; muscle fiber. The neuromuscular junction is the point of connection between the axon of an alpha motor neuron and a muscle fiber. This is where the nerve signal is transmitted from the neuron to the muscle, causing it to contract.

The dorsal horn is responsible for receiving sensory information from the peripheral nerves and transmitting it to the brain, while the ventral horn is responsible for sending motor signals from the brain to the muscles. This means that the dorsal horn is associated with afferent pathways (carrying information towards the central nervous system), while the ventral horn is associated with efferent pathways (carrying information away from the central nervous system). Therefore, the correct answer is afferent; efferent.

The gamma motor neuron is responsible for tightening intrafusal muscle fibers when the muscle contracts. This is important because it allows the muscle to continue to react to the environment even when it is contracted. By tightening these fibers, the muscle is able to maintain its sensitivity to changes in the environment and respond accordingly. This helps to ensure that the muscle can adapt and continue to function effectively, even during periods of contraction.

Intrafusal fibers do not feed extrafusal fibers ATP. Intrafusal fibers are specialized muscle fibers found within muscle spindles, which are sensory organs that detect changes in muscle length and tension. They are innervated by both afferent and efferent nerve fibers. Afferent fibers report the length of intrafusal fibers to the central nervous system, while efferent fibers adjust the sensitivity of afferent fibers. Extrafusal fibers, on the other hand, are the regular skeletal muscle fibers responsible for generating force and movement.

Smooth muscles are not directly controlled by the central nervous system. Unlike skeletal muscles, which are under voluntary control, smooth muscles are controlled involuntarily by the autonomic nervous system. The autonomic nervous system consists of the sympathetic and parasympathetic divisions, which regulate the contraction and relaxation of smooth muscles. Therefore, the statement that smooth muscles are controlled by the central nervous system is untrue.

The motor homunculus is a map of the body in which body parts are proportional to the sensitivity of the body part. This means that the size of each body part on the map corresponds to the level of sensitivity or the amount of sensory input that body part receives. For example, the hands and face, which are highly sensitive, are represented by larger areas on the map compared to less sensitive body parts like the legs or back. This map helps researchers and scientists understand the organization and representation of sensory information in the brain.

Myosin is a protein that moves actin filaments using ATP. During muscle contraction, myosin binds to actin and uses ATP to generate the force necessary for muscle movement. Therefore, the correct answer is myosin; actin.

The statement "Release of ACh triggers myosin to pull further apart" is not true because the release of ACh actually triggers myosin to bind to actin and pull closer together, causing muscle contraction.

not-available-via-ai

not-available-via-ai