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Why does optimum pH promote enzyme activity?

One example of an enzyme is lipase. According to Elmhurst College, lipase breaks down lipid triglycerides, or fats. According to Worthington Biochemical Corporation, lipase in the stomach works best when the pH is between 4.0 and 5.0. If the pH falls below 4.0 or rises above 5.0, lipase function decreases and may even stop, preventing the body from breaking down fats in the digestive system. Optimal pH varies for different enzymes.

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What are the three states of matter?

Solids are rigid substances that have definite shapes and volumes. The molecules in a solid are rigidly positioned close to one another, so the molecules cannot move around much. Liquids have defined volumes but no actual shape. Liquids take the shape of the container they inhabit, and their molecules flow past one another but are still touching each other. Gases have neither defined shapes nor volumes. Molecules in gases do not lie against one another; instead, wide spaces separate the gas molecules and they move past each other freely.

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How many electrons does titanium have?

Titanium is the ninth most common element on Earth; it is found in igneous rocks and sediments. It is hard, lustrous and strong as steel but much less dense. Commercially, it is used as an alloy agent in projects that require great structure strength but low overall weight, such as aircraft and missiles.Titanium is also a common component of desalinization plants and ship hulls because it does not corrode in the presence of seawater like other metals. Unlike other metals, it connects well with bone and it is used frequently to repair damaged joints and teeth.

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Is there a relationship with global warming and Hurricane Sandy?

Hurricane Sandy began, as all hurricanes do, as a tropical storm over the Atlantic Ocean. The prevailing winds at those latitudes pushed it west toward North America. As it traveled over the ocean, the storm that would become Hurricane Sandy gained strength from water evaporating off the ocean surface. When it grew large enough, Sandy organized as a cyclonic storm and was assigned a name.\nThe role global warming plays in hurricane formation is that of an accelerant. In cool climates, less energy is available to drive the evaporation of water. Tropical weather patterns have less energy availab..

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How do you get pregnant with quintuplets?

Multiple babies that come from one divided egg are known as monozygotic multiples. Monozygotic multiples are genetically identical, meaning they are the same gender and look very similar. Monozygotic multiples occur in every three to four out of one thousand births. Whether or not one egg splits into many eggs is entirely random, meaning age, race and genetics have no influence.\nMultiple babies born at once can also come from multiple eggs that are all fertilized by different sperm cells. These multiples are known as dizygotic multiples. Because they are made from different eggs and sperm, di..

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What does the esophagus do in the digestive system?

The esophagus has two muscular control points, called sphincters. Similar to sphincters in other portions of the body, when the muscles in the sphincter contract, they prevent liquids from passing through. The esophagus features two sphincters, one at each end. The upper esophageal sphincter is involved in swallowing and breathing and is usually under an animal’s conscious control. By contrast, the lower esophageal sphincter, which prevents stomach acids or food from travelling back up the esophagus, is not usually under direct, voluntary control.\nIf the lower esophageal sphincter does not ..

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How old is man?

Anatomically modern humans are a subspecies of the larger species, Homo sapiens, which includes other extinct subspecies, such as Homo sapiens idaltu, Homo sapiens neanderthalis, Homo sapiens heidelbergensis, Homo sapiens rhodesiensis and Homo sapiens antecessor. The last three listed are considered archaic human groups, while the Neanderthals are a separate group that possibly interbred with early modern human groups.

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Are there differences in the smell of men's and women's urine?

Estratetraenol is a steroid hormone that researchers suspect may be a human pheromone, states Scientific American. It has no discernible odor of its own, but experiments have shown that the human nose can perceive it.\nOnly in female urine contains estratetraenol. A similar compound, androstadienone, is a male hormone, but can also be present in women's secretions, explains Scientific American.\nA study involving human perception of both compounds found that straight men perceived a gender-neutral walking animation as more feminine after sniffing estratetraenol, Scientific American repor..

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What muscles abduct your leg?

Abduction is just movement of the leg to the side, not forward or backward. Arms are abducted by reaching out from the shoulder. Jumping jacks abduct all four limbs of the body by moving legs apart and to the side while moving arms to the side and then up. Leg lifts done by lying on the side strengthen hip abductors. Workout machines move these muscles, but the same motions are achieved by cable machines.\nGetting the leg to move forward and backward is called flexing or extending, respectively. These actions differ from abduction since abducting muscles just moves limbs to the side. Hip flexi..

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What are the harmful effects of microorganisms?

In some cases, microorganisms can have beneficial effects in small populations, but an overgrowth can cause issues. For instance, the bacteria that lives inside the human digestive tract, when balanced by other microbes in the body, serves an important purpose in the digestive process. However, an imbalance of nutrients or a weakened immune system can allow bacteria populations to grow, leading to an intestinal infection and potentially to a dangerous illness.

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