There are ten major organ systems in the body, each of which plays a different role in helping the body work. This system is made up of the heart, blood, blood vessels, and lymphatics. The purpose of the digestive system is to turn the food you eat into something useful for the body. When you eat, your body uses this system to digest food so your cells can use it to make energy. The organs involved in this system include the mouth, stomach, and intestines.
This system is made up of a collection of glands, including the pituitary and thyroid glands, as well as the ovaries and testes. It regulates, coordinates, and controls a number of body functions by secreting chemicals into the bloodstream.
These secretions help control moods, growth and development, and metabolism. This system consists of the skin, hair, nails, and sweat glands. Its main function is to act as a barrier to protect the body from the outside world. It also functions to retain body fluids, protect against disease, eliminate waste products, and regulate body temperature. This system is made up of muscle tissue that helps move the body and move materials through the body.
Table 1 describes the structures and functions of some common organs. Organ systems are made up of organs that work together to perform a specific function for the body as a whole. Table 2 describes the organ systems and their primary organs and physiological functions that we will cover in subsequent pages. For example, we have placed the reproductive system in the control category since it is involved in controlling the process and events of reproduction.
However, the reproductive system is also a cell maintenance system, as it produces and maintains the actual cells used in reproduction. Just keep in mind these are groupings to help you mentally organize your learning more than they hard rules of anatomy and physiology. The organ systems of the body all work together to maintain proper physiological functions.
Many times in the arena of anatomy and physiology, including in this course, we closely examine the molecules, cells, tissues and organs of the body to learn their forms and functions. However, it is important to consider that every molecule works as part of the entire system. Endocrine disorders such as diabetes affect glucose levels in the body. Altered blood glucose levels can affect many organ systems. For example, the immune system may not heal as well, the urinary system may experience kidney damage, and the cardiovascular system can experience vascular damage, even to the point of causing blindness.
In the body, everything is interconnected. In fact, most organs contribute to more than one system. Figure 1. Click for a larger image. Organs that work together are grouped into organ systems. Each organ system performs specific functions for the body, and each organ system is typically studied independently.
However, the organ systems also work together to help the body maintain homeostasis. For example, the cardiovascular, urinary, and lymphatic systems all help the body control water balance. The cardiovascular and lymphatic systems transport fluids throughout the body and help sense both solute and water levels and regulate pressure.
If the water level gets too high, the urinary system produces more dilute urine urine with a higher water content to help eliminate the excess water. If the water level gets too low, more concentrated urine is produced so that water is conserved. Similarly, the cardiovascular, integumentary skin and associated structures , respiratory, and muscular systems work together to help the body maintain a stable internal temperature. This allows heat to dissipate through the skin and into the surrounding air.
The skin may also produce sweat if the body gets too hot; when the sweat evaporates, it helps to cool the body. Rapid breathing can also help the body eliminate excess heat. Together, these responses to increased body temperature explain why you sweat, pant, and become red in the face when you exercise hard.
Heavy breathing during exercise is also one way the body gets more oxygen to your muscles, and gets rid of the extra carbon dioxide produced by the muscles. Conversely, if your body is too cold, blood vessels in the skin contract, and blood flow to the extremities arms and legs slows. Muscles contract and relax rapidly, which generates heat to keep you warm. The hair on your skin rises, trapping more air, which is a good insulator, near your skin.
So what happens when you have a fever? Does this mean your body is unable to maintain its homeostasis, in the same way your house will get too hot if your air conditioner is broken? In extreme cases, a fever can be a medical emergency; but fever is an adaptive physiological response of our body to certain infectious agents.
Certain chemicals called pyrogens will trigger your hypothalamus to shift the set point to a higher value. This is more like you programming the thermostat in your house to a higher temperature to save energy on a hot day when you are not going to be home during the day.
These pyrogens can come from microorganisms that infect you, or they can be produced by your body cells in response to an infection of some sort. The increased temperature may actually impair the replication of infecting bacteria and viruses that are adapted to survive best at your normal homeostatic body temperature range. This can give your immune cells a chance to destroy the microorganisms before they can rapidly multiply and spread in the body.
There is also some indirect evidence that increased body temperature slightly modifies several metabolic reactions in ways that also allow the immune system to function more efficiently. As long as the pyrogen levels continue to increase and decrease you will feel like you are swinging back and forth.
Body functions such as regulation of the heartbeat, contraction of muscles, activation of enzymes, and cellular communication require tightly regulated calcium levels. Normally, we get a lot of calcium from our diet.
It also provides the body with strength and stability. The fascia and connective tissues provide a framework for holding all of us together and allowing us to maintain our function in the face of gravity. This system is controlled by the nervous system. All of your adult bones make up the skeletal system, giving the body internal structure and form. This system provides compression strength and the ability to resist tension that is necessary for motion and work in our environments.
This system is made up of your skin and hair, or your exterior defense system against outside entities and atmospheres. This system protects you from hot and cold temperatures, dust, allergens, and more. Skin is one of the first barriers to viruses and other pathogens and is subject to a lot of oxidative stress. This is your internalized signaling system made up of your brain, nerves, ganglia, and spinal cord. The nervous system is responsible for transmitting sensations and commands throughout the body.
It controls both your conscious and unconscious bodily processes like moving, breathing, and blinking. The nervous system allows basic electrical signals to be interpreted into our feelings and sensations. The digestive system is composed of organs such as the pancreas, stomach, liver, intestines, and gallbladder that can process food and nutrients that enter the body.
The lining of the digestive system is another primary barrier to pathogens like viruses. This system works directly with the digestive system. The urinary system including the kidneys, bladder, and urinary organs is in charge of excreting waste substances from the body, absorbing nutrients before excretion, and detoxifying our systems.
The female reproductive system is made up of the uterus and ovaries while the male reproductive system includes the prostate and testis. This biological system is in charge of sexual reproduction. This is the unifying system of all other systems. This is the regulatory system that ensures balance in all other functions of the body. This is the background code running in your human-computer that allows the software of the other 12 systems to be useful.
Now that we have defined these systems, why are they important, and how do they function together so seamlessly? Each system relies on the others in order to keep the body healthy and working correctly. Here are a few examples:. When one of these systems is not functioning properly , you are guaranteed to feel this imbalance throughout the other systems within your body.
If your immune system is left unable to protect the body from outside dangers, your reproductive system and nervous systems are left vulnerable to illness.
0コメント