Functional Organization of Human Body PDF

1) Functional organisation of human body Q: What is physiology? Physiology is the science that studies the physical and chemical mechanisms responsible for the origin, development, a...

1) Functional organisation of human body Q: What is physiology? Physiology is the science that studies the physical and chemical mechanisms responsible for the origin, development, and progression of life in living things (from viruses to humans). What are the different subfields of A: The field of physiology can be divided into physiology? many subfields, including viral physiology, bacterial physiology, cellular physiology, plant physiology, invertebrate physiology, vertebrate physiology, mammalian physiology, and human physiology. Q: What is the main function of human Human physiology focuses on understanding physiology? the specific characteristics and mechanisms that make the human body function as a living being. This includes complex control systems that drive our basic needs and behaviors and how these systems integrate with cells, tissues, and organs to maintain health. Q: How do complex control systems help A: Hunger makes us seek food, fear makes humans survive? us seek refuge, and sensations of cold make us look for warmth. These are all examples of complex control systems that help us meet our basic needs and survive. What is the basic unit of life in the human The cell is the basic unit of life in the human body? body. Trillions of cells work together to form tissues and organs. What are some of the similar characteristics Most cells use oxygen to produce energy of most cells? from nutrients (carbohydrates, fat, and protein). They also release waste products from their chemical reactions. Additionally, almost all cells can reproduce to create new cells. What is the role of microbes in the human A: The human body is inhabited by trillions of body? microbes, outnumbering human cells. These microbes live on the skin, in the mouth, gut, and nose. Can microbes be harmful? While some microbes can cause diseases, most live in harmony with us and play vital roles in digestion, immunity, and other bodily functions. What is the “internal environment” of the body : The “internal environment” of the body is called? called the extracellular fluid or milieu intérieur. What is the importance of extracellular fluid? All cells live in essentially the same environment—the extracellular fluid. It contains the ions and nutrients needed by the cells to maintain life. How do the concentrations of substances The extracellular fluid contains high amounts differ between extracellular and intracellular of sodium, chloride, and bicarbonate ions, fluids? while the intracellular fluid has high amounts of potassium, magnesium, and phosphate ions. Special mechanisms maintain these differences. What is homeostasis? Homeostasis is the maintenance of nearly constant conditions in the internal environment of the body. How do different organs and tissues Essentially, all organs and tissues of the body contribute to homeostasis? perform functions that help maintain these relatively constant internal conditions. For example, the lungs provide oxygen, the kidneys maintain ion concentrations, and the digestive system provides nutrients and eliminates waste How tightly are the various body constituents The various constituents of the body are regulated? normally regulated within a range of values, rather than at fixed values. Some variations, like blood hydrogen ion concentration, are extremely small, while others, like blood sodium concentration, have a wider range. What are the consequences of disrupted Disease is often considered to be a state of homeostasis? disrupted homeostasis. Even in disease, homeostatic mechanisms continue to operate and maintain vital functions through compensations. These compensations can sometimes lead to further complications. What is the field of pathophysiology Pathophysiology seeks to explain how the concerned with? various physiological processes are altered in  diseases or injury. How is extracellular fluid transported Extracellular fluid is transported in two throughout the body? stages: blood circulating through blood vessels and movement of fluid between capillaries and intercellular spaces. What is the function of the capillaries? The capillaries are tiny blood vessels that allow for the exchange of fluids and dissolved molecules between the blood plasma and the interstitial fluid. How does the respiratory system contribute The respiratory system allows oxygen to to the extracellular fluid? diffuse from the alveoli into the blood stream, becoming part of the extracellular fluid. What role does the gastrointestinal tract play The gastrointestinal tract absorbs nutrients in the extracellular fluid? from digested food into the blood stream, adding them to the extracellular fluid. How do the liver and other organs contribute The liver and other organs process absorbed to the extracellular fluid? substances from the gastrointestinal tract into more usable forms, modify them for storage, or eliminate waste products, all of which contribute to the composition of the extracellular fluid. How does the respiratory system remove The respiratory system removes carbon waste products from the body? dioxide, a waste product of cellular metabolism, from the blood stream into the alveoli where it is expelled during exhalation. What is the function of the kidneys in relation The kidneys filter waste products, excess to the extracellular fluid? ions, and water from the blood plasma, excreting them in urine. They also reabsorb necessary substances like glucose and amino acids back into the bloodstream. How does the gastrointestinal tract contribute The gastrointestinal tract eliminates to waste removal? undigested materials and some waste products of metabolism in the feces. How does the liver contribute to waste The liver detoxifies ingested drugs and removal? chemicals, excreting them in the bile to be eliminated in the feces. How does the nervous system help maintain The nervous system has two main parts: homeostasis? sensory input and motor output. Sensory receptors detect changes in the body and environment, sending signals to the central  nervous system (brain and spinal cord) which interprets the information and sends instructions via motor output to maintain homeostasis. The autonomic nervous system specifically controls many internal organ functions like heart rate, digestion, and gland secretion. How do hormones contribute to The endocrine system releases hormones homeostasis? that travel through the extracellular fluid to target organs, regulating cellular function. Hormones like thyroid hormone, insulin, and parathyroid hormone control various processes such as metabolic rate, blood sugar levels, and calcium balance. The nervous system and hormonal system work together to regulate nearly all bodily functions. How does the immune system protect the The immune system differentiates between body? the body's own cells and foreign invaders (pathogens like bacteria and viruses). It then destroys these invaders through phagocytosis or by producing antibodies to neutralize them. How does the integumentary system The skin and its appendages (hair, nails, contribute to homeostasis? glands) act as a barrier between the body and the external environment, protecting tissues and organs. It also plays a role in temperature regulation, waste excretion, and sensory perception. How is reproduction related to homeostasis? While not typically considered a homeostatic function, reproduction helps maintain homeostasis by creating new individuals to replace those that die, ensuring the continuation of the species. This reinforces the idea that all bodily systems ultimately work together to sustain life.