Histamines in the human body cause the contractions of muscle tissue in the lungs, uterus and stomach, according to Encyclopaedia Britannica. Histamines also dilate blood vessels, accelerate the heart rate and increase stomach acid production. This protein serves as a neurotransmitter between the nervous system and other cells in the body. Systemically, the most obvious sign of a histamine reaction is inflammation.Know More
Encyclopaedia Britannica indicates histamines activate during an immune response within the body. At an injury site, histamines cause more permeability in cell membranes, which allows fluids, white blood cells and blood plasma proteins to arrive more quickly than normal. Special cells in the body called mast cells release histamines in injured tissue to begin the immune system response.
An allergic reaction occurs in the human body when histamines believe harmless substances such as dust or pollen are invading germs, according to the Biology Department at Davidson College. Histamines increase swelling in bronchial tubes within the lungs during asthmatic reactions when external stimuli enter the organs. Medicines known as antihistamines help control these allergic responses. Allergies that cause histamine reactions are not normal because dust and pollen are not dangerous to the human immune system.
Histamines are released in large amounts during an allergic reaction. Massive amounts of histamines released in the body cause systemic reactions such as sneezing, coughing, runny nose and itchy eyes, explains IMS Health Incorporated.Learn more in Medications & Vitamins
The maximum temperature of a Bunsen burner flame is 1500 degrees Celsius, or 2700 degrees Fahrenheit, according to Encyclopaedia Britannica. The warmest part of the Bunsen burner flame is located above the tip of the primary flame.Full Answer >
Volcanology is the study of volcanoes, according to Encyclopaedia Britannica. Volcanology deals with the classification, formation and the distribution of volcanoes in various parts of the world.Full Answer >
Narwhals inhabit the Arctic region and feed on squid, shrimp and fish, according to Encyclopaedia Britannica. Due to their prominent tusks, narwhals are nicknamed the "unicorns of the sea" and hunted by Inuit populations as an ivory and food source.Full Answer >
Before arriving in North America, the Pilgrim leaders, including William Bradford and William Brewster, developed the Mayflower Compact to establish a provisional government and prevent civil disorder in their new settlement, according to the Encyclopaedia Britannica. Forty-one adult males on the voyage were required to sign the document, which was a formal pledge to adhere to future laws created by the governing body.Full Answer >