Learn how organisms maintain homeostasis, or a stable internal environment.
Can someone explain what is negative feedback? I didn't understand the concept from the article.... • (14 votes) From what I understood, negative feedbacks is your body's response to keep things normal or stable, whereas positive feedbacks exacerbate certain effects on the body by repeating functions deliberately. In essence, negative feedbacks preserve your body's original or 'set' condition and positive feedbacks do the opposite and change you body more by constantly pushing certain types of growth or development in the same direction until something has been accomplished. The example they used was a fetus's head constantly putting more and more pressure on the cervix until birth. Since this is very necessary and important, a positive feedback loops is run: the substance that pushes the fetus' head towards the cervix, oxytocin, is released as a cause of contractions from the uterus, which are themselves a cause of pressure from the fetus' head on the cervix. So the pressure essentially causes contractions in the uterus which stimulate nerve impulses in the brain to release more oxytocin, which further increase the pressure of the fetus' head. Clearly the goal isn't to maintain the fetus' current state but rather push it to the point where it is primed for birth. (34 votes) Is the system that regulates pH, homeostasis? • (6 votes) To be precise, homeostasis is a process/phenomenon not a system. Homeostasis is actually the process of maintaining a stable internal environment despite changes in the external environment. There are mechanisms in organisms that regulate pH and this regulation is an example of homeostasis. For example, if you have learned about buffers, then it may help to know that essentially all organisms use buffers (and other mechanisms) to maintain control over the pH — for example the different organelles within eukaryotic cells will consistently have different pHs: Does that help? (20 votes) what is pH guys and how does it relate to homeostasis. • (5 votes) pH is a measure of how acidic or basic a solution is. More specifically, pH=-log[H+], which essentially means that the more positively charged hydrogen ions you have in a volume of solution, the lower the pH is and the more acidic the solution is. You can also check out this video (if you haven’t already seen it): https://www.khanacademy.org/science/high-school-biology/hs-biology-foundations/hs-ph-acids-and-bases/v/introduction-to-ph pH matters for homeostasis because it’s part of the chemical environment in which biochemical reactions have to take place. For example, enzymes (which help speed up chemical reactions in living things) have ranges of pH where they work best. Because these molecules’ proper functioning is necessary, pH is very important for maintaining homeostasis. Hope this helps! (19 votes) How can very low temperatures be fatal? • (4 votes) Low temperatures would mean that the enzymes would be inactive or they may not be able to catalyse as much. This slows down reactions in the body (lowers metabolism), meaning that you may be deprived of essential things such as energy etc, which can eventually lead to complications such as death. (15 votes) can someone please tell me which organ in the body controls homeostasis? • (3 votes) Homeostasis is mainly controlled by the organs in the central nervous system and the endocrine system (hormones). Organs in the two systems send commands to other organs in other systems to allow them to carry out certain functions. Example for the nervous system: You have stepped outside into some snowy weather. It is cold outside, and your body temperature is dropping. The nervous system sends signals to the muscles that tell them to shake. The shaking of the muscles generates heat, keeping you warm. Example for the endocrine system: Unfortunately, your have not eaten anything for hours. This results in a low blood sugar level. To maintain homeostasis, cells from the pancreas release a hormone known as glucagon, which raises your blood sugar by decreasing the storage of sugar in body cells. Does this help you? (14 votes) How does Blood clot relate to Homeostasis? • (4 votes) Blood clotting is considered part of the Positive Feedback (PF) Loop. This is defined as an effector that will AMPLIFY the effect of the Negative Feedback (NF) Loop. For instance, when there is a hemorrhage (loss of blood), it will cause a sequential activation of clotting factors. Here, a single clotting factor results in the activation of many more clotting factors. This is also known as a PF cascade. This overall process will give the completion of the NF Loop because blood loss was prevented with the clotting factors, resulting in Homeostasis. (11 votes) What system controls homeostasis? • (3 votes) There are many different systems that organisms use to maintain homeostasis. For example, the processes used for thermoregulation in mammals and birds are very different from the methods used to keep pH relatively constant. (11 votes) what is the control center in temperature homeostasis hot? • (5 votes) The control center for temperature is the hypothalamus. (6 votes) I understand how homeostasis happens in our bodies, but why does it occur? Furthermore, why do we need it? Why do we try to control the internal functions of our bodies rather than the external stimuli that cause them? Why are there not more uses of positive feedback loops? • (3 votes) Positive feedback loops could get out of control. It could continue to accelerate and amplify and this is not desirable for organisms that would like to maintain specific set points. (3 votes) How can blood vessels dilate result in heat loss？ • (4 votes) This is because the dilation of blood vessels increases their surface area making it easier for the blood to interact and transfer heat with cooler parts of the body, generally the more surface area, the more heat loss. (3 votes)Want to join the conversation?
http://book.bionumbers.org/what-is-the-ph-of-a-cell/
