Biology Chapter 7 Flashcards

Questions and Answers

Describe and differentiate between external and internal respiration.

External respiration moves gases from outside of the body into the lungs, and then into the blood. Internal respiration is the gas exchange between the blood and the tissues. Both processes are linked through the circulatory system, facilitating the delivery of oxygen to tissues.

Describe the mechanisms involved in inspiration and expiration.

Inspiration involves the intercostal muscles and the diaphragm, moving the ribs and sternum while the diaphragm contracts and flattens. Expiration is the relaxation of the elastic recoil of the lungs, with the diaphragm returning to its normal position and the intercostals relaxing.

What is a spirometer? Describe and define the lung volumes measured using spirometry.

A spirometer is a tool used to measure volumes of inspired and expired air. Key lung volumes include tidal volume (amount of air for one breath), vital capacity (greatest amount of air expired after maximum inspiration), and residual volume (air remaining after maximal expiration).

Explain the concept of partial pressures of respiratory gases.

Partial pressure refers to the individual pressure of each gas in a mixture. In inhaled air, oxygen is 20.93%, CO2 is 0.03%, and nitrogen is 79.04%. This pressure gradient facilitates gas exchange. Signup and view all the answers

Where in the lung does the exchange of gases with the blood occur?

The exchange occurs in the respiratory membrane, composed of the alveolar wall, capillary wall, and their basement membranes, providing a pressure gradient for diffusion. Signup and view all the answers

How are oxygen and carbon dioxide transported in the blood?

Oxygen is transported by combining with hemoglobin or dissolving in plasma, while carbon dioxide is carried as bicarbonate ions, dissolved in plasma, or bound to hemoglobin. Signup and view all the answers

How is oxygen unloaded from the arterial blood to the muscle and carbon dioxide removed from the muscle?

Oxygen is delivered to muscles via myoglobin and released when PO2 is low, while CO2 diffuses out of muscle cells back into the blood, leading to the lungs. Signup and view all the answers

What is meant by the arterial-mixed venous oxygen difference?

It refers to the difference in oxygen content between venous and arterial blood. During intense exercise, more oxygen is delivered to active muscles, resulting in a lower PO2 in venous blood. Signup and view all the answers

Describe how pulmonary ventilation is regulated.

Respiratory centers in the brain stem control motor neurons that regulate the respiratory muscles. Changes in CO2 and H+ levels influence the depth and rate of breathing. Signup and view all the answers

Define the term 'inspiration'.

Inspiration is an active process involving the diaphragm and the external intercostal muscles. Signup and view all the answers

Define the term 'expiration'.

Expiration is a passive process involving the relaxation of inspiratory muscles and the elastic recoil of lung tissue. Signup and view all the answers

What is pulmonary diffusion?

Pulmonary diffusion is the process by which gases are exchanged across the respiratory membrane in the alveoli to the blood and vice versa. Signup and view all the answers

What is Dalton's law?

Dalton's law states that the total pressure in a mixture of gases is equal to the sum of the individual partial pressures. Signup and view all the answers

What does TLC stand for?

Total Lung Capacity. Signup and view all the answers

What does VC stand for?

Vital Capacity. Signup and view all the answers

What does TV stand for?

Tidal Volume. Signup and view all the answers

What does IC stand for?

Inspiratory Capacity. Signup and view all the answers

What does IRV stand for?

Inspiratory Reserve Volume. Signup and view all the answers

What does EC stand for?

Expiratory Capacity. Signup and view all the answers

What does ERV stand for?

Expiratory Reserve Volume. Signup and view all the answers

What does RV stand for?

Residual Volume. Signup and view all the answers

What does FEV stand for?

Forced Expiratory Volume. Signup and view all the answers

What does FVC stand for?

Forced Vital Capacity. Signup and view all the answers

What does FER stand for?

Forced Expiratory Ratios. Signup and view all the answers

What does PEF stand for?

Peak Expiratory Flow. Signup and view all the answers

Study Notes

External and Internal Respiration

External respiration involves gas exchange from the environment to the lungs, then to the bloodstream.
Internal respiration refers to gas exchange between the blood and body tissues.

Mechanisms of Breathing

Inspiration engages intercostal muscles and the diaphragm, lifting the ribs and flattening the diaphragm.
Expiration is a passive process where elastic recoil of lung tissue causes air to exit as muscles relax.

Spirometry and Lung Volumes

A spirometer measures inspired and expired air volumes, indicating lung capacity changes.
Key lung volumes include:
- Tidal Volume (TV): air exchanged in normal breathing.
- Vital Capacity (VC): maximal air expelled post-inspiration.
- Residual Volume (RV): air remaining after maximum expiration.

Partial Pressures in Gas Exchange

Partial pressure reflects the individual pressure exerted by each gas in a mixture, critical for gas exchange.
Oxygen constitutes 20.93%, CO2 0.03%, and nitrogen 79.04% of air, establishing a pressure gradient for diffusion.

Gas Exchange Location and Mechanism

Gas exchange occurs at the respiratory membrane, composed of alveolar and capillary walls.
A pressure gradient facilitates diffusion of gases across the membrane.

Transport of Gases in Blood

Oxygen is transported bound to hemoglobin or dissolved in plasma.
Carbon dioxide is carried as bicarbonate ions, dissolved in plasma, or bound to hemoglobin.

Oxygen Unloading and CO2 Removal

Myoglobin in muscle cells transports oxygen to mitochondria, releasing it when tissue PO2 is low.
CO2 diffuses from muscle cells into the blood for transport back to lungs.

Arterial-Mixed Venous Oxygen Difference

This difference measures oxygen content between venous and arterial blood.
During exercise, active muscles require more oxygen, leading to a greater difference.

Regulation of Pulmonary Ventilation

Respiratory centers in the brain stem regulate breathing rate and depth by responding to changes in CO2 and H+ levels.
Increased breathing occurs during exercise to expel excess CO2 and H+.

Definitions of Key Terms

Inspiration: Active process involving diaphragm and external intercostal muscles.
Expiration: Passive process involving muscular relaxation and lung elastic recoil.
Pulmonary Diffusion: Gas exchange across the alveolar respiratory membrane.
Dalton's Law: Total pressure of a gas mixture equals the sum of individual gas partial pressures.
Total Lung Capacity (TLC): Total volume of air lungs can hold.
Forced Vital Capacity (FVC): Volume of air expelled forcefully after maximum inhalation.
Peak Expiratory Flow (PEF): Maximum flow rate during early forced expiration.

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Description

Test your knowledge of respiratory processes with these flashcards covering key concepts in Chapter 7 of biology. Differentiate between external and internal respiration, and understand their significance in gas exchange. Perfect for reinforcing your understanding of the respiratory system.