Physiological stress

Definition

Physiological stress refers to the biological responses of organisms when they face unfavorable environmental conditions that exceed their ability to cope. In the context of marine organisms, factors such as temperature increases, salinity changes, and pollution can lead to metabolic strain and hinder normal physiological functions. Understanding this concept is crucial for assessing how ocean warming impacts the health, behavior, and survival of marine species.

5 Must Know Facts For Your Next Test

1. Physiological stress can lead to decreased reproductive success in marine organisms as energy is diverted from reproduction to deal with stressors.
2. Increased ocean temperatures can elevate metabolic rates, resulting in higher energy demands that can lead to mortality if not met.
3. Physiological stress may also impair immune responses in marine organisms, making them more susceptible to diseases.
4. Chronic exposure to physiological stress can lead to changes in behavior, such as altered feeding patterns and habitat use.
5. Different species have varying thresholds for physiological stress, meaning some may adapt better to ocean warming than others.

Review Questions

• How does physiological stress affect the reproductive success of marine organisms?
  • Physiological stress diverts energy away from reproduction as organisms prioritize coping with unfavorable conditions. This redirection of energy can result in lower reproductive output and increased embryo mortality rates. Over time, these effects can significantly impact population dynamics and biodiversity within marine ecosystems.
• Discuss the role of thermal tolerance in relation to physiological stress and ocean warming.
  • Thermal tolerance is a critical factor in how marine organisms cope with rising ocean temperatures. Species with high thermal tolerance are better equipped to handle physiological stress associated with increased heat. However, as ocean temperatures continue to rise beyond these thresholds, even tolerant species may experience heightened stress, affecting their survival and overall ecosystem health.
• Evaluate the long-term ecological implications of physiological stress on marine biodiversity in the context of ongoing climate change.
  • Long-term physiological stress due to climate change poses significant threats to marine biodiversity. Species unable to acclimatize or adapt may face population declines or extinctions, leading to shifts in community structures. This can disrupt food webs and ecosystem functions, ultimately diminishing resilience against other environmental changes and impacting human activities dependent on healthy marine ecosystems.

Related terms

Metabolic Rate: The rate at which an organism converts food into energy, which can increase due to physiological stress, impacting growth and reproduction.

Acclimatization:

The process by which organisms adjust to changes in their environment over time to reduce physiological stress.

Thermal Tolerance:

The ability of an organism to withstand variations in temperature, which can be compromised due to physiological stress from ocean warming.