How do animals maintain homeostasis? Let’s Know & Understand the Concepts
Maintaining homeostasis is actually to maintain the internal body temperature, pH level, oxygen, glucose, mineral ions, waste removal, etc. toward a relatively stable equilibrium.
In simple words, homeostasis is the body’s attempt to maintain a constant and balanced internal environment. This will help in the proper functioning of the body.
The animal body works from the inside to maintain the homeostasis of the biological body and its various processes with respect to the changes held in the external environment by Negative Feedback loops.
All living organisms, must regulate their internal body environment by homeostasis to process energy and ultimately survive. Thus, homeostasis is very much important for the living body.
Here in this post we will learn more about it and how it works. So, let’s get started…
How do animals maintain homeostasis?
The animal body needs persistent monitoring and adjustments to maintain homeostasis as conditions change from time to time.
Animals maintain homeostasis with the help of the receptors, the command center in the brain, and the effectors of the body. These work together to regulate, monitor, and adjust the animal body’s equilibrium.
The job of the receptors is to receive information about the changes in the external environment and transmit it to the control center of the brain.
The control center receives and processes information from the receptors to the effectors.
Getting the response from the control center, the effector responds to the commands of the control center by either opposing or enhancing the stimulus.
This whole co-ordination and co-operation of the receptor, the command center, and the effector works continuously to maintain the negative feedback loop which in turn maintains the homeostasis.
Thus, Negative Feedback Loop is the stimulation and signalling roadway that maintains homeostasis. Thus, the negative feedback loop serves to reduce an excessive response and to keep a variable within the normal range.
For example: When the external environment’s temperature increases, then the animal body needs to maintain homeostasis by regulating the internal body temperature. Thus, for doing so, the temperature receptors in the skin communicate information to the brain (the control center) which then signals the effectors blood vessels and sweat glands for keeping the body cool.
Another example is of the Negative feedback loop to maintain homeostasis that can be seen when the blood glucose levels increases after eating sweet foods. This signals the pancreas to secrete insulin. The insulin stimulates the absorption of glucose and the conversion of glucose into glycogen, which is stored in the liver.
However, as the blood glucose levels decrease, less insulin is produced. And, when glucose levels gets too low, another hormone called glucagon is produced, which causes the liver to convert the glycogen back to glucose.
IN SIMPLE WORDS: How do animals maintain homeostasis?
In simple words, the maintenance of homeostasis usually involves the various negative feedback loops which involves the proper working of the receptors, control center of the brain, and the effectors respectively. These feedback loops act to oppose the stimulus, that triggers them.
For example, if your body temperature is too high, a negative feedback loop will act to bring it back down towards the set point, or target value, of 37°C.
How do animal cells maintain homeostasis? – (An Overview)
Cells maintain homeostasis by keeping the intracellular ionic concentration, pH level, water balance, cytosol viscosity, membrane fluidity all in an equilibrium balanced state. This helps the cell to stay active, living, growing, and in a cell dividing/reproducing state.
One way that a cell maintains homeostasis is by controlling the movement of substances across the cell membrane. We know that, all cells have semi-fluid phospholipid bilayer cell membrane.
This cell membrane is non-permeable to ions, proteins, and other molecules, while permeable to other molecules that may move through the membrane.
The two mechanisms by which molecules are transported across the cell membrane are through active transport and passive transport. This active and passive transport ways are the main processes that maintains the cell equilibrium.
Thus, cell transport helps cells to maintain homeostasis by keeping conditions within normal ranges inside all of an organism’s cells.
Now, the movement of water in and out of the cell helps to maintain the proper cytosol viscosity and fluidity required in order to maintain cell homeostasis.
Now, in order to maintain the cell’s pH, the animal cell removes lysosomes outside the cell which contains all of the unwanted proteins, DNAs, RNAs, carbohydrates, fats, and other cell organelles that are being digested forming acidic contents inside the lysosome.
Another one is by cell signaling way in which one cell helps the other to maintain homeostasis. Cells communicate with each other by cell signaling to tell one another that there’s a problem in the intracellular equilibrium that is to be fixed.
Cell signaling is done by signaling the target cell from the source cell for regaining the balance of homeostasis in the cells.
What controls and maintains homeostasis?
The controlling of homeostasis is done by the working of the sensory receptors, control center, and by the effector cells by getting stimulated from the cue of external environment. This is the control system.
While the maintenance of homeostasis is done by the working of the negative feedback loop that has been resulted due to the control system. A negative feedback loop is a reaction that causes a decrease in function so, the feedback tends to stabilize the system.
For example, if we take the maintenance and controlling of an animal’s internal body temperature when the external environment gets hot. Then, it is seen the animal body tries to maintain homeostasis by cooling itself.
Let’s understand this example of homeostasis and learn how the controlling and maintenance of homeostasis takes place:
- External Cue/Stimulus: This is the signal that the body gets from the external environment. Here, the body feels very hot when the temperature of the external environment is too high.
- Receptors: As the body feels hot, the nerve receptors in the skin feels the external cue and passes this signal to the control center of the brain.
- Control Center of the Brain: Here, the skin receptors passes the signal to the thermoregulatory center in the hypothalamus. Here, in this example, the thermoregulatory center in the hypothalamus is the control center of the brain.
- Effectors: Here, in this example, the thermoregulatory center in the hypothalamus will now signal the skin’s sweat glands to release sweat and also signal the blood vessels to increase blood flow towards the skin.
- Negative Feedback Loop: This feedback loop will act to oppose the external stimulus, that has triggered it. Here, the hot temperature is the external stimulus that has triggered it, and so, as a result, the control system is maintained to cool the body’s temperature.
How the homeostasis is maintained? With some examples provided in the table below:
| Ex No. | Homeostasis Type | Stimulus | Receptor | Control Center | Effector |
|---|---|---|---|---|---|
| 1. | Thermoregulation | When the external body temperature becomes hot or cold | Skin cells | Thermoreceptors in the hypothalamus, spinal cord, internal organs, and great veins | Skin cells and blood vessels |
| 2. | Blood Glucose | Increase in glucose in the blood | β-cells of Pancreatic islets | Hypothalamus of the brain | Liver, fat cells, and muscle cells |
| 3. | Blood gases | Changes in the levels of oxygen, carbon dioxide, and plasma pH | Central chemoreceptors in the cerebrospinal fluid | Respiratory center of the medulla oblongata | Diaphragm and other muscles of respiration |
| 4. | Calcium levels | The increased Calcium (Ca2+) concentration in the blood | Parathyroid glands, parafollicular cells, thyroid gland | Endocrine system | Bones, kidneys, parathyroid hormone (PTH), calcitonin |
| 5. | Sodium concentration | When the Sodium (Na+) concentration in the blood increases | Juxtaglomerular apparatus of kidneys | Osmoreceptors (specialized protein receptors) in the hypothalamus | Juxtaglomerular cells releasing renin |
Why is homeostasis important for animals?
Homeostasis is very much important for animals to maintain a stable internal balance in their body. This stability is actually the internal state of equilibrium of the animal’s body that allows the animals to function in the changing external conditions surrounding their body.
Homeostasis is very much important to all of the cellular functioning and working in the body like cellular catabolism, anabolism, respiration, exocytosis, endocytosis, reproduction, cell growth, etc. that are taking place inside the animal body. Thus, homeostasis helps in the proper functioning of the cells to help in its survival and ability to reproduce.
Osmosis is very much important to living organisms, like for moving materials into and out of the cell, and moving important nutrients and wastes dissolved in water in and out of the cell. Osmoregulation is the process of carrying osmosis due to homeostasis and it is the way osmosis is controlled to maintain water balance inside their body.
Homeostasis is a dynamic process that requires constant monitoring of all systems in the body to detect changes, and perform the various internal body mechanisms that react to those changes and restore stability by a negative feedback loop to oppose the stimulus generated from the external environment.
All of the functioning of the cells, tissues, organs, and organ systems like the respiratory system, digestive system, integumentary system, endocrine system, etc. are well-maintained and are now functioning properly all because of homeostasis.
Even the time and how we sleep depends on sleep homeostasis. Sleep homeostasis regulates wakefulness and sleep. Sleep pressure is generated by sleep homeostasis and builds up with the amount of time being awake. This helps the body to take rest and relax with a nap.
Homeostasis helps the body to aestivate in summers and hibernate in winters and also to stay inactive during the time of the very harsh conditions. During such harsh days, it regulates and maintains the body with the lowest requirements and lowest metabolic functioning of the body.
Homeostasis helps the body to thermoregulate and adapt to their ecosystem. Homeostasis is highly developed in warm-blooded animals living on land, which must maintain body temperature, fluid balance, blood pH, and oxygen tension within the required value.
Being able to maintain homeostasis even in extremely adverse conditions is one of the most important evolutionary advantages.
If we particularly talk about the circulatory system then the maintenance of proper healthy blood pressure is an example of homeostasis. The heart acting as a receptor can sense changes in blood pressure which is the stimulus, thus sending signals to the brain (control center), which then sends appropriate instructions back to the heart which now acts as the effector.
Which organelle is responsible for cell homeostasis?
The cell membrane is mostly responsible for cell homeostasis. This membrane keeps the cell structure intact and helps in the proper functioning of the cell by selectively allowing what goes in and out of the cell.
The cell membrane is non-permeable to ions, proteins, and other molecules while being permeable to other molecules that may move through the membrane. This helps to maintain proper cell homeostasis.
The role of ribosomes in cell homeostatsis can’t also be ignored. The ribosomes help in the proper production of proteins by catalyzing the DNA/RNA translation. Thus, the balanced amount of proteins are formed that helps to maintain the cell wall and other organelles and also in cell signalling and protection.
Another one is the lysosome. In addition to its role in nutrient sensing, the lysosome contributes to energy homeostasis through its direct role in the mobilization of energy stores.
The lysosome also maintains the body homeostasis by making new rooms for new cells. It is filled with enzymes that can digest things. And so, when a cell is about to die, lysosome bursts to eat up the dead cell leaving space for new cells to come.
Mitochondria also help maintain the environment of the cell by performing homeostasis in ATP energy production and in the respiration biochemical cycle. It is also to be noted that both cellular proliferation and cell division are regulated by the mitochondria.
If we talk about molecular biology and genetic point of view, then it is also to be noted that the nucleus helps the cell to maintain homeostasis by regulating gene expression.
The nucleus can also cause downregulating of the synthesis of rRNA and ribosome biogenesis depending on the external stimulus.
The Endoplasmic Reticulum (ER) is also a very important cell organelle. The ER membrane is the prominent site of various proteins, lipids, and glucose metabolism, lipoprotein secretion, and calcium homeostasis taking place within the cell.
Just, for example, the ER is also the major intracellular calcium storage compartment that maintains cellular calcium homeostasis.
What happens if homeostasis fails and is disrupted?
If homeostasis fails and is disrupted than the body won’t be able to be in equilibrium with that of the external environment.
And so, if properly the equilibrium is not being maintained then the body won’t be able to function properly due to excess, or deficiency, or non-availability of something in the body.
If the homeostasis balance is disrupted than the body will starve due to the non-availability of many things that are taking part in the biochemical cycles inside the body.
So, homeostatic imbalance and disruption may lead to a state of various diseases taking place in the body.
However, if homeostasis fails, then this may lead to major diseases taking place in the body and the body will starve to survive. Thus, this can also cause death.
In simple words, if homeostasis fails and is disrupted, then this may result in an abnormal functioning of the various organs of the body.
For example: The blood pressure increases due to the increase in sugar(glucose) in the blood when the concentration of insulin in the blood increases than the normal range. Then, the body cells don’t take up glucose readily, and so the blood sugar levels remain high for a long period of time after a meal. This causes the disease called Diabetes due to the imbalance of glucose homeostasis in the blood.
Now, Diabetes happens when a person’s pancreas can’t make enough insulin, or when cells in the body stop responding to insulin just like in the above example.
