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Physiological Adaptation Definition
Physiological adaptation is a metabolic or physiologic alteration inside an organism’s cell or tissues in response to an external stimulus that improves the organism’s ability to deal with its changing environment. It might also be the organism’s response to particular external stimuli in order to preserve homeostasis.
Physiological adaptations include skin browning through prolonged sun exposure, the creation of calluses on hands from repetitive contact or pressure, and the capacity of some organisms to absorb nutrients under low oxygen pressures.
What is Physiological Adaptation?
When we examine evolutionary history, we see that neither the most brilliant and intellectual individuals nor the strongest and most durable individuals overcome the difficulties given by nature. Nature, on the evolutionary time scale, chooses the most adapted species to continue the biological journey.
Adaptation is a biological process in which a species adjusts to almost any environmental changes (both genotypically and phenotypically). Only those species with high “biological fitness,” or the capacity to adapt to changes in one’s environment, will be picked by nature to pass on their genes to the next generation, according to Charles Darwin. Adaptations are, therefore, essentially the product of natural selection.
Physiological adaptations, out of all the many types of adaptations, have the highest diversity, roles, and relevance in virtually all forms of life on this planet. When asked what physiological adaptation is, the answer is “a series of continuous intracellular, biochemical, and metabolic modifications inside an organism’s body to keep it in balance under any kind of external circumstance.”
This sort of adaptability is dynamic in nature since it changes through time and takes many forms depending on the organism’s circumstances. Plant and animal adaptation to their environment is the fundamental driving factor for species survival and reproduction, regardless of how severe the environmental, climatic, resource, or niche competition is.
Nature presents each species with a variety of obstacles from time to time. It might be a search for:
1. a suitable area to reside in
2. resource availability (food, water, sunlight, nutrients, etc.)
3. Struggle for a mate (to produce progeny and pass on genes)
As a result, we understand that all of these difficulties present themselves to an organism or species as a variety of stimuli. Challenges bring a lot of strain and tension with them. Species evolve a set of “adaptive responses” to cope with these stressors over millions of years.
Types of Adaptation
Structural adaptations, behavioural adaptations, and physiological adaptations are the three categories of adaptations.
i. Structural Adaptation
Role: Over time, bring modifications to a species’ physical structure to make it physically prepared. Changes in body size, colour, organ form, and appendages are only a few examples.
Adaptation’s nature: Usually inheritable and related to generational changes.
1. Desert plants grow strong stems and shortened leaves called spines as a heat-coping strategy in the plant world. These bodily modifications aid in their ability to adapt to severe temperatures.
2. Camouflage is a wonderful example in the animal realm. Chameleons may avoid predators by changing their physical appearance, such as colour, and becoming invisible to the naked sight.
ii. Behavioural Adaptation
Role: In charge of changes in behaviour and the manner in which individuals of a species behave. Migratory skills, hibernation, insect capturing abilities in insectivorous plants, and bird and mammal mating habits are only a few examples.
Adaptation is learned by each organism of the species during its lifespan, rather than being passed down from generation to generation.
1. Tropisms, such as phototropism, thigmotropism, gravitropism, and others, are behavioural adaptations in plants. To optimise photosynthetic output, plants grow their branches toward the source of light.
2. Birds’ migratory activity is essential in the animal kingdom because it allows them to withstand the harsh conditions of one of their primary habitats. They migrate from one environment to the next in search of food, shelter, and a place to breed.
iii. Physiological Adaptation
These adaptations are an organism’s physiological reactions to changes in its micro- and macroenvironment. They work at the cellular, physiological, metabolic, and biochemical levels to increase an organism’s ability to adapt to changing environmental conditions.
Physiological adaptation is defined in biology as “changes in an organism’s fundamental metabolome to preserve homeostasis despite the worst of environmental conditions and trends.” It’s critical to grasp two key words at this point: metabolome and homeostasis.
1. The metabolome is a collection of all the metabolites generated by all of the cells in an organism’s body as a result of the metabolic processes that it performs to maintain life and fundamental functions. The metabolome provides a clear assessment and readout of an organism’s physiological features and state. To adjust to severe circumstances, the body’s cells must function differently, resulting in the production of a new or modified spectrum of metabolites that can help in acclimatisation.
2. Homeostasis is the body’s technique for maintaining a relatively steady balance. The balance between two key elements determines whether the body will remain in this natural physiological equilibrium or not: new external conditions and the organism’s capacity to adapt.
Nature of Physiological Adaptation
There are many differing viewpoints on whether it is inheritable or not. Any cellular ability of an organism is supposed to be governed by the genetic make-up of the organism. Since physiological adaptation is a manifestation of cellular and metabolic changes, it should be genetically determined and hence pass down from generation to generation.
Physiological adaptations, on the other hand, do not appear to be inheritable or genetically determined, but rather acquirable in one’s own lifetime, because an organism is extremely capable of acquiring internal modifications throughout its lifespan in response to changing external circumstances (such as tanning).
Adaptation in biology refers to an organism’s behaviour, physiology, and structure being adjusted or changed to make it more suited or suitable to its environment. The creatures adapt to their environment to become more suited to live and pass their genes on to the next generation, according to Charles Darwin’s theory of evolution by natural selection.
Physiological adaptation, as contrast to evolutionary adaptation, which includes transgenerational adjustment, is often limited in scope and involves an individual’s reaction to a specific, usually limited spectrum of stimuli.
Physiological Adaptation Function
The following are a few of them:
1. Physiological adaptations help organisms survive in their natural habitats.
2. Physiological adaptations help proper development and growth.
3. Physiological adaptations assist inside the body’s temperature, pressure, ionic balances, and metabolic rates monitoring. 4.Physiological adaptations help save resources (water/nutrients) or maximise resources (sunlight/ions).
Physiological Adaptation Examples
Physiological adaptations in several kingdoms include:
i. Fungi and Bacteria
1. Antibiotic and antifungal resistance development: Bacteria and fungi are extremely fast-evolving organisms with a wide range of population diversity. The harsh conditions induced by these anti-growth drugs compel fast, spontaneous mutations. When resistant bacteria proliferate, they get a significant capacity to spread even when antibiotics are used.
2. Heavy metal resistance: R-plasmids (resistance plasmids) transmit different forms of resistance to bacteria, including heavy metal resistance, such as mercury resistance, which can be deadly if not addressed.
3. Antifreeze proteins: Antifreeze proteins were initially discovered in mammals and then subsequently in plants. These proteins inhibit the development and growth of ice crystals outside of the cell, saving the cells from cell membrane damage caused by the crystal structure.
1. The carbon concentration and fixation mechanism (cam) is a temporal separation mechanism for carbon concentration and fixation. Arid-zone plants concentrate CO2 only at night in order to decrease evapotranspiration and fix carbon during the day. Pineapple, jade, cactus, and other plants have this physiological adaptability.
2. Poison production: Numerous plants, such as stinging nettle plants and many nightshade plants, have venom-producing systems to defend themselves against herbivores.
3. Seed dormancy in coastal plants: Seeds of coastal plants have evolved to become dormant and germinate when conditions become favourable, due to very salty environments. Mangroves, for example.
iii. Animals and Humans
Animals must adapt to their surroundings in order to operate efficiently in any given habitat. Adaptations in animals include the following:
1. Venom production: This is a physicochemical adaptation that aids animals in warding off predators and capturing prey more readily. Snakes, bees, and spiders are among the examples.
2. Urine concentration: Because desert animals live in dry, arid, and harsh environments, they require an animal adaptation that allows them to thrive even in the face of severe water shortages. Their kidneys have a modified urine concentration mechanism for this. Fennec foxes, camels, and other animals are examples.
3. Offensive odour production: Skunks create a unique, unpleasant chemical that they spray to keep away any possible predators or competitors.
4. Tanning (in humans): This is the most significant adaptation for human populations living in the 23-46 oC temperature range, as UVB levels and intensities change depending on the season.
5. HIIT (in humans): A number of recent studies have found that high-intensity interval training (HIIT) improves human endurance and helps people avoid many of the chronic health problems that come with modern lives. It works at the physiological level of the cell, increasing mitochondrial biogenesis in human body cells and therefore enabling them.
iv. The Venus Flytrap
1. Structural: The structure of this insectivorous plant is the result of millions of years of structural evolution. The fundamental structural structure is designed such that when an insect lands and the mechanosensors detect a touch signal, the trap closes spontaneously.
2. Behavioural: The behavioural element is the closure mechanism, which is activated by electrical charge transmission. The trap closes only when a specific potential is reached.
3. Physiological: The production of nectar across the brims of the leaves to attract prey, as well as the presence of digestive enzymes inside the plant to metabolise and digest the insects, are the last physiological aspects of adaptation.
Physiological Adaptation Citations
- Physiological adaptation in early human pregnancy: adaptation to balance maternal-fetal demands. Appl Physiol Nutr Metab . 2006 Feb;31(1):1-11.
- Physiological adaptation to the humid tropics with special reference to the West African Dwarf (WAD) goat. Trop Anim Health Prod . 2009 Oct;41(7):1005-16.
- Complexity and network dynamics in physiological adaptation: an integrated view. Physiol Behav . 2014 May 28;131:49-56.
- The Biology of Physiological Health. Cell . 2020 Apr 16;181(2):250-269.