which of the following structures prevents food from entering the windpipe

ATI TEAS 7

Practice TEAS Science Test

1. Which of the following structures prevents food from entering the windpipe?

A. Pharynx
B. Esophagus
C. Larynx
D. Epiglottis

Correct answer: D

Rationale: The epiglottis is the structure that prevents food from entering the windpipe by covering the trachea during swallowing. When food is swallowed, the epiglottis folds over the opening of the trachea to ensure that food goes down the esophagus and not into the airway. The pharynx is a shared pathway for both food and air, leading to the esophagus and larynx respectively. The esophagus is the muscular tube that carries food from the throat to the stomach. The larynx is responsible for producing sound and protecting the airway during swallowing, but the epiglottis is specifically designed to prevent food from entering the windpipe.

2. Which law of motion states that for every action, there is an equal and opposite reaction?

A. Newton's First Law
B. Newton's Second Law
C. Newton's Third Law
D. Law of Universal Gravitation

Correct answer: C

Rationale: The correct answer is Newton's Third Law of Motion. This law states that for every action, there is an equal and opposite reaction. It means that when one object exerts a force on a second object, the second object exerts an equal force in the opposite direction back on the first object. This fundamental law describes the relationship between the forces acting on two interacting objects. Newton's First Law (Choice A) is known as the law of inertia and states that an object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an external force. Newton's Second Law (Choice B) relates the force acting on an object to its mass and acceleration. The Law of Universal Gravitation (Choice D) describes the force of gravity between two objects with mass and the distance between them.

3. Which of the following meninges is a thin membrane containing numerous nerves and blood vessels that supply nourishment to the underlying brain cells and spinal cord?

A. Arachnoid mater
B. Dura mater
C. Periosteum
D. Pia mater

Correct answer: D

Rationale: The pia mater is the correct answer. It is a thin, innermost layer of the meninges that contains numerous nerves and blood vessels, providing nourishment to the underlying brain cells and spinal cord. The arachnoid mater (Choice A) is the middle layer of the meninges and does not contain as many nerves and blood vessels as the pia mater. The dura mater (Choice B) is the tough, outermost layer of the meninges and is not responsible for supplying nourishment. The periosteum (Choice C) is a connective tissue membrane covering bones, not part of the meninges.

4. What is hydroxyapatite?

A. A mixture of minerals such as calcium and phosphorus that strengthen the collagen matrix of bone.
B. The structural unit of a bone that runs the length of the bone.
C. The covering of bones at the point of articulation to prevent grinding.
D. The lightest portion of a long bone and concentrated at the ends.

Correct answer: A

Rationale: Hydroxyapatite is a mineral compound composed of calcium and phosphorus that plays a crucial role in strengthening the collagen matrix of bones, contributing to their structural integrity and hardness. It is a key component of bone tissue and provides the mineralization necessary for bone strength and density. Choice B is incorrect because the structural unit of a bone is the osteon or Haversian system, not hydroxyapatite. Choice C is incorrect as it describes cartilage, not hydroxyapatite. Choice D is incorrect as it refers to the epiphysis, which is not synonymous with hydroxyapatite.

5. The fossil record shows that dinosaurs with feathers existed millions of years before birds. This is evidence for

A. Convergent evolution (unrelated organisms evolving similar traits)
B. Divergent evolution (related organisms evolving different traits)
C. Coevolution (two species influencing each other's evolution)
D. The extinction of dinosaurs due to an asteroid impact

Correct answer: A

Rationale: The fossil record indicates that dinosaurs had feathers before birds, suggesting convergent evolution. Convergent evolution occurs when unrelated organisms independently evolve similar traits to adapt to similar environmental pressures. In this case, both dinosaurs and birds developed feathers for flight or insulation purposes, even though they are not closely related. This evidence supports the concept of convergent evolution rather than divergent evolution, coevolution, or the extinction of dinosaurs due to an asteroid impact. Therefore, the correct answer is A, as it best explains the scenario where dinosaurs with feathers existed before birds, showcasing the concept of unrelated organisms evolving similar traits independently.