Problem 11 - Biology of Humans: Concepts, Applications, and Issues

Question

In emphysema, a. the number of alveoli is reduced. b. cartilage rings in the trachea break down. c. the diaphragm is paralyzed. d. the epiglottis becomes less mobile.

Step-by-Step Solution

Answer

a. the number of alveoli is reduced.

Step 1: Understanding Emphysema

Emphysema is a chronic lung condition that primarily affects the alveoli, which are the tiny air sacs in the lungs responsible for gas exchange.

Step 2: Evaluating Option a

Option a states that the number of alveoli is reduced. Emphysema damages the alveoli and reduces their number, impairing lung function.

Step 3: Evaluating Option b

Option b involves the breakdown of cartilage rings in the trachea. Emphysema does not typically involve the trachea or its cartilage rings.

Step 4: Evaluating Option c

Option c claims that the diaphragm is paralyzed. Emphysema primarily affects the alveoli, not the diaphragm, although it may lead to breathing difficulty.

Step 5: Evaluating Option d

Option d suggests that the epiglottis becomes less mobile. Emphysema does not typically affect the epiglottis.

Step 6: Choosing the Correct Answer

Given the evaluations, the only option that correctly describes a primary effect of emphysema is option a: the number of alveoli is reduced.

Key Concepts

Alveoli

Alveoli are tiny, balloon-like structures in the lungs that play a crucial role in the respiratory system. They are located at the end of bronchioles, the small passages in the lungs. The primary function of alveoli is to facilitate gas exchange. Oxygen passes through the alveolar walls into the blood, and carbon dioxide moves from the blood into the alveoli to be exhaled.
In emphysema, the alveoli are damaged. The walls of the alveoli can break down, leading to fewer and larger air sacs instead of many tiny ones. This process reduces the surface area available for gas exchange, making it harder for the body to get enough oxygen and remove carbon dioxide effectively.

Lung Function

Lung function refers to how well your lungs work during breathing. Healthy lungs efficiently exchange gases—oxygen and carbon dioxide—between the air and your blood. This process includes:

• Inhaling oxygen into the lungs
• Oxygen passing through the alveoli into the bloodstream
• Carbon dioxide passing from the blood into the alveoli
• Exhaling carbon dioxide out of the lungs

Emphysema impairs these functions by damaging the alveoli, leading to less effective gas exchange. The lungs lose their elasticity, making it harder for them to expel air. This results in trapped air in the lungs, breathlessness, and decreased oxygen levels in the blood.

Respiratory System

The respiratory system consists of several organs and structures that help in breathing. The main parts include the nose, trachea, bronchi, lungs, and diaphragm. The key roles of the respiratory system are:

• Delivering oxygen to the blood
• Removing carbon dioxide from the blood

In emphysema, the respiratory system, particularly the lungs and alveoli, are compromised. Damaged alveoli and loss of lung elasticity disrupt the normal airflow and gas exchange, leading to symptoms like shortness of breath and chronic cough. While other parts of the respiratory system, like the trachea and diaphragm, may assist in breathing, they are not the primary sites affected in emphysema.

Chronic Lung Condition

A chronic lung condition is a long-lasting illness that affects the lungs and breathing. Emphysema is one such condition, classified under chronic obstructive pulmonary disease (COPD). Key characteristics of chronic lung conditions include:

• Long-term breathing difficulties
• Progressive nature, meaning it worsens over time
• Symptoms like cough, wheezing, and shortness of breath

Emphysema specifically involves the gradual destruction of alveoli, leading to reduced lung function. The condition is usually caused by long-term exposure to airborne irritants like tobacco smoke. Managing emphysema often involves stopping smoking, using bronchodilators, and undergoing pulmonary rehabilitation to maintain lung function as much as possible.