BIOS 255 Week 7 Respiratory System-Physiology

Name

Chamberlain University

BIOS-255: Anatomy & Physiology III with Lab

Prof. Name

Date

Respiratory System – Physiology

Learning Objectives:

Explain the physiological adaptations of the cardiorespiratory system of seals to deep diving.

Identify differences between seal and human physiology related to deep diving.

Evaluate respiratory and cardiac function.

Measure oxygen consumption and calculate the total amount of oxygen needed for dives of various durations, comparing this to estimated stores in the lungs, blood, and tissues.

Introduction:

Active cells constantly require oxygen to produce energy and carry out cellular processes. This energy production results in carbon dioxide, a waste product that must be removed from the body, as its buildup is toxic to cells. The respiratory rate, or the number of breaths per minute, and the depth of respiration are controlled by the respiratory center in the brainstem. This center ensures that respiratory effort meets the body’s metabolic demands.

In this lab, we will explore the physiological adaptations of seals, specifically Weddell seals, that allow them to perform long, deep dives, sometimes reaching depths of up to 600 meters and lasting up to 30 minutes. Seals possess specialized adaptations that allow them to store oxygen and manage aerobic and anaerobic energy generation. These unique features enable them to dive for much longer periods than humans. By monitoring three dives and collecting data on oxygen and lactate levels, we will learn about oxygen stores, the aerobic dive limit, and the differences in oxygen storage between seals and humans.

Assignment:

Part 1: Complete the Labster simulation, “Cardiorespiratory Physiology: How Can Seals Dive So Deep for So Long?” Record data throughout the lab. The theory section provides valuable information.
Part 2: Complete the lab report.

Respiratory Physiology Lab Report:

Parameter	Weddell Seal	Human
Diving depth	600 meters, over an hour without taking breaths	35.5 meters, only for a few short minutes
mL O2 in lungs	1200 mL/min	900 mL/min
mL O2 in blood	21950 mL/min	1005 mL/min
mL O2 in muscle	9005 mL/min	188 mL/min
Total mL O2 in stores before the dive	32155 mL/min	2093 mL/min
% of Oxygen in blood	71%	59%
% of Oxygen in muscle	25%	16%
% of Oxygen in lungs	4%	25%
Aerobic dive limit (predicted)	10.2 minutes (if same factorial increase as humans)	1.4 minutes
Aerobic dive limit (actual)	23.8 minutes

Parameter

Weddell Seal

Human

Diving depth

600 meters, over an hour without taking breaths

35.5 meters, only for a few short minutes

mL O2 in lungs

1200 mL/min

900 mL/min

mL O2 in blood

21950 mL/min

1005 mL/min

mL O2 in muscle

9005 mL/min

188 mL/min

Total mL O2 in stores before the dive

32155 mL/min

2093 mL/min

% of Oxygen in blood

71%

59%

% of Oxygen in muscle

25%

16%

% of Oxygen in lungs

25%

Aerobic dive limit (predicted)

10.2 minutes (if same factorial increase as humans)

1.4 minutes

Aerobic dive limit (actual)

23.8 minutes

Main Difference in Oxygen Stores:
Unlike humans, who fill their lungs with air before diving, seals exhale to avoid the bends caused by nitrogen bubbles under pressure. Seals experience increasing pressure as they dive deeper, with the pressure doubling every 10 meters.

Greatest Proportion of Oxygen Stored in Humans:
Oxygen is stored in the blood (hemoglobin) and muscle (myoglobin). Seals, with their larger red blood cells and higher concentrations of oxygen-storing hemoglobin, store more oxygen in their blood compared to humans.

Factorial Increase in Oxygen Consumption:
Seals do not exhibit the same factorial increase in oxygen consumption as humans. Instead, they can dive for much longer periods due to their reduced oxygen consumption during diving. Weddell seals can dive 16 times longer than the average human.

Oxygen Consumption for 12-Minute vs 30-Minute Dives:
During a 12-minute dive, the seal used 4.88 mL/min of oxygen, while for a 30-minute dive, the seal used 4.48 mL/min. This shows that the oxygen consumption rate does not increase significantly, even during longer dives.

Lactate Accumulation:
During the 12-minute dive, there was no lactate accumulation. However, in the 30-minute dive, lactate levels increased from 2 mmol/liter at rest to 10 mmol/liter. This suggests that the 30-minute dive exceeded the aerobic dive limit, requiring partial anaerobic metabolism to meet the energy demands.

Seal’s Heart Response to Diving:
During a dive, the seal’s heart rate drops to conserve oxygen and energy, allowing it to sustain longer dives.

Heart Rate and Oxygen Consumption Patterns:
In a 30-minute dive, the seal’s heart rate slows, and its oxygen consumption remains stable or decreases slightly. This reflects the seal’s efficient oxygen management and energy conservation during diving.

Incorrect Statement About Seal Adaptations:
The incorrect statement is that seals have larger lungs than humans per body mass. In fact, seals have smaller lungs relative to their body mass compared to humans.

How the Respiratory and Circulatory Systems Complement Each Other:
The seal’s respiratory system allows its lungs to compress under pressure, preventing bends. The circulatory system, with its large blood volume and high oxygen content, works with the respiratory system to store and distribute oxygen efficiently during a dive.

BIOS 255 Week 7 Respiratory System-Physiology