Which of the following is not a primary taste sensation?
Sour
Sweet
Salty
Pungent
The Correct Answer is D
Taste (gustation) is a special sensory modality mediated by taste buds located primarily on the tongue, soft palate, and oropharynx. These receptors detect dissolved chemical substances and transmit signals via cranial nerves VII, IX, and X to the gustatory cortex. The primary taste sensations are classically defined as sweet, salty, sour, bitter, and umami. These basic tastes represent fundamental chemical qualities required for nutrient detection and toxin avoidance. Other sensations like pungency are not true tastes but are instead mediated through different sensory pathways.
A. Sour: Sour taste is a primary gustatory sensation mediated by hydrogen ion concentration in acidic substances. These ions stimulate ion channels in taste receptor cells, particularly on the sides of the tongue. The signal is transmitted via cranial nerves IX and VII to the brainstem and gustatory cortex. Sour taste plays a protective role by helping detect potentially spoiled or unripe foods.
B. Sweet: Sweet taste is a primary taste modality triggered by sugars and certain amino acids. It is detected by G-protein-coupled receptors (T1R family) located in taste buds. These receptors initiate intracellular signaling cascades that send impulses through cranial nerves VII and IX. Sweet taste is important for identifying energy-rich nutrients such as carbohydrates.
C. Salty: Salty taste is detected primarily through sodium ion channels in taste receptor cells. When sodium ions enter these channels, they depolarize the cell membrane and generate a neural signal. This information is transmitted via cranial nerves VII and IX to the brain for interpretation. Salty taste helps regulate electrolyte balance and hydration status.
D. Pungent: Pungent sensation is not a true taste but a chemesthetic response mediated by the trigeminal nerve (cranial nerve V). It is triggered by irritants such as capsaicin in chili peppers, which activate pain and temperature receptors rather than taste buds. This produces sensations of burning or heat rather than a chemical taste quality. Since it does not arise from gustatory receptors or taste buds, pungent is not classified as a primary taste sensation.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is C
Explanation
The marked structure is the biceps brachii, a prominent muscle of the anterior compartment of the upper arm. It has two heads (long and short) originating from the scapula and inserting on the radial tuberosity of the radius. It crosses both the shoulder and elbow joints, making it a biarticular muscle involved in both shoulder stabilization and forearm movement. Its primary physiological functions include elbow flexion and forearm supination, especially when the forearm is in a flexed position.
A. Triceps brachii: The triceps brachii is located in the posterior compartment of the upper arm and is the primary extensor of the elbow joint. It has three heads (long, lateral, and medial) and inserts on the olecranon process of the ulna. Unlike the biceps brachii, it functions to straighten the elbow rather than flex it. Its posterior position and extensor role differentiate it from the anteriorly located biceps.
B. Brachialis: The brachialis lies deep to the biceps brachii in the anterior arm and is the strongest pure flexor of the elbow joint. It originates from the distal half of the humerus and inserts on the ulna. Unlike the biceps brachii, it does not cross the shoulder joint or contribute to forearm supination. It is a deeper muscle and not typically visible as the prominent anterior arm contour.
C. Biceps brachii: The biceps brachii is a superficial anterior arm muscle with two heads originating from the scapula (supraglenoid tubercle and coracoid process). It inserts on the radial tuberosity and via the bicipital aponeurosis into the forearm fascia. It functions in elbow flexion and powerful forearm supination. Its superficial position and characteristic bulge in the anterior upper arm make it the correct identification.
D. Brachioradialis: The brachioradialis is a forearm muscle located on the lateral aspect of the forearm. It originates from the lateral supracondylar ridge of the humerus and inserts on the distal radius. It assists in elbow flexion, especially in mid-pronation/supination positions. Unlike the biceps brachii, it is primarily a forearm muscle and does not create the prominent anterior upper arm contour.
Correct Answer is A
Explanation
The vertebra is a complex irregular bone designed to provide structural support, flexibility, and protection for the spinal cord. It consists of a central body, a vertebral arch, and several specialized bony projections that serve as attachment points for muscles and ligaments. In the image, the structure marked with an "X" is one of the lateral projections extending from the vertebral arch, which is essential for stabilizing the vertebral column and facilitating movement through muscular pull.
A. The transverse process is the lateral bony projection that extends from the junction of the pedicle and lamina on each side of the vertebra. These processes serve as critical attachment sites for deep back muscles and, in the thoracic region, articulate with the ribs. The structure marked with an "X" is clearly identified as this lateral projection.
B. The spinous process is the singular, posterior-facing projection located at the midline of the vertebral arch. It is easily palpable through the skin along the back and serves as an anchor for various ligaments and muscles that support the spine. It is distinct from the lateral structure marked in the image, which originates from the side of the arch.
C. The superior articular facet is a smooth surface on the superior aspect of the vertebral arch that articulates with the inferior articular facet of the vertebra above it. These facets are crucial for limiting movement and maintaining the alignment of the vertebral column. They are located near the pedicle-lamina junction but are not the lateral extension identified by the "X" in the image.
D. The vertebral foramen is the large, central opening created by the vertebral arch and the posterior surface of the vertebral body. It houses the spinal cord, its associated protective meninges, and the surrounding blood vessels. The mark "X" is placed on the external lateral surface of the bone, not within this central canal.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.