Chapter 34, Problem 18A

Summary Introduction

Introduction:

The respiratory system is the connection between organs and tissues that controls our breathing. It consists of our airways, lungs, and blood vessels. The muscles that strengthen our lungs are additional components of the respiratory system. These parts function together to support our body to absorb oxygen from the air so our organs can function. It additionally cleans waste gases, such as carbon dioxide, from our blood. Common troubles consist of allergies, diseases, or infections.

Answer to Problem 18A

Correct answer:

The correct answer is option (B) diaphragm.

Explanation of Solution

Explanation/justification for the correct answer:

Option (B) diaphragm.The diaphragm is a narrow skeletal muscle that sits at the bottom of the chest and separates the stomach from the chest. It contracts and flattens while we inhale. This produces a vacuum impact that pulls air into the lungs. So, the correct answer is option B.

Explanation for incorrect answer:

Option (A) trachea. It is a cartilaginous tube that links the larynx to the bronchi of the lungs, permitting the passage of air, and so is located in almost all air- respiring animals with lungs. So, this is an incorrect answer.

Option (C) pharynx. The pharynx is the part of the digestive tract that receive meals from our mouth. Branching off the pharynx is the esophagus, which transfers food to our stomach. So, this is an incorrect answer.

Option (D) ribs. The ribs are the bony framework of the thoracic cavity. The ribs shape the primary structure of the thoracic cage shielding or saving the thoracic organs; however, their major function is to aid respiration. So, this is an incorrect answer.