BIOS 255 Week 7 Respiratory System-Physiology

BIOS 255 Week 7 Respiratory System-Physiology

Student Name

Chamberlain University

BIOS-255: Anatomy & Physiology III with Lab

Prof. Name:

Date

Week 7 Respiratory System – Physiology

Learning Objectives

The focus of this week’s lab is to explore and understand the physiological adaptations of the cardiorespiratory system in seals during deep diving. The specific objectives include:

1. Physiological Adaptations: To explain the adaptations in seals’ cardiorespiratory systems that enable them to dive deeply and for extended durations.
2. Comparative Analysis: To identify and highlight the differences between seal and human physiology during deep dives.
3. Evaluation and Measurement: To evaluate respiratory and cardiac function by measuring oxygen consumption, calculating oxygen requirements for dives of varying durations, and comparing these to estimated oxygen stores in the lungs, blood, and tissues.

Introduction

Active cells continuously require oxygen for energy production and expel carbon dioxide as a waste product. To maintain cellular function, the body replenishes oxygen and eliminates carbon dioxide through respiration, which is regulated by the brainstem’s respiratory center. This center ensures that respiratory effort aligns with the body’s metabolic demands.

This week’s lab takes you to a research lab in Antarctica to study how Weddell seals, which can dive as deep as 600 meters for 30 minutes, have developed unique physiological adaptations for deep dives. Through this simulation, you will examine oxygen stores, aerobic dive limits, and the mechanisms of ATP production (aerobic and anaerobic) in seals, as well as their specialized cardiorespiratory adaptations. These insights will also enhance your understanding of human cardiorespiratory physiology.

Humans and seals differ significantly in oxygen storage and utilization during dives. You will monitor three dives, analyzing oxygen consumption and lactate levels to uncover these differences.

Assignment

• Part 1: Complete the Labster simulation titled “Cardio-respiratory Physiology: How can seals dive so deep for so long?” Record your observations and data in the provided lab report during the simulation.
• Part 2: Complete the lab report, which will include analysis and interpretation of the data collected.

Comparative Table of Diving Depths and Oxygen Stores

Key Observations and Questions

1. Differences in Oxygen Stores
   Seals store most of their oxygen in blood and muscles, while humans store more in their lungs. This distribution is influenced by seals’ larger red blood cells, higher hemoglobin content, and reduced lung capacity as a percentage of body mass.

2. Oxygen Consumption and Dive Duration
   Seals exhibit lower factorial increases in oxygen consumption during dives compared to humans, allowing them to dive 16 times longer. For example, oxygen consumption during a 12-minute dive was approximately 4.88 mL/min, whereas during a 30-minute dive, it was slightly lower at 4.48 mL/min.

3. Anaerobic vs. Aerobic Metabolism
   During a 30-minute dive, 20% of ATP production was anaerobic, leading to lactate accumulation (10 mmol/L), whereas no lactate was detected during a 12-minute dive, which relied solely on aerobic metabolism.

4. Cardiac Adaptations
   Seal heart rates drop significantly during dives, reducing oxygen consumption and conserving energy. This bradycardia, coupled with efficient gliding through water, helps minimize energy expenditure.

5. Respiratory and Circulatory Coordination
   Seals’ respiratory and circulatory systems work in tandem. Their reinforced lungs compress under pressure to avoid nitrogen narcosis, and their large blood volume stores most of their oxygen in hemoglobin.

References

American Physiological Society. (2024). Cardio-respiratory physiology of diving seals.
Labster. (2024). Cardio-respiratory Physiology: How can seals dive so deep for so long?

BIOS 255 Week 7 Respiratory System-Physiology

Smith, J., & Brown, L. (2023). Comparative physiology of diving mammals. Journal of Marine Biology, 89(4), 567-580.