The endocrine system is made up of a number of glands that secrete hormones. Glands and the hormones they release regulate many processes in the body; from growth, puberty, metabolism and reproduction, hormones play a role in almost everything we do
The correct answer is: There are 20 primary teeth, and by 24 months of age most children have all 20.
Primary teeth also known as deciduous teeth, milk teeth, are the first set of temporary teeth in the growth development of humans. They develop during the embryonic stage of development, become visible in the mouth during infancy (erupt) and usually get replaced by permanent teeth around age six (the first tooth). The primary teeth consist of 4 central incisors (one in each quadrant), 4 lateral incisors, 4 canines, 4 first molars, and 4 secondary molars.
Antarctic fish species requires an adaptation to cold environment. Living at cold temperature environment would demand certain biological responses such as cutaneous respiration, enlarged blood vessels, and producing greater amounts of fat. Most of these fat are composed of higher phospolipid levels which are primarily due to phosphatidylethanolamine. This phospolipid is responsible for destabilizing cell membranes and make it more fluid thereby allowing unrestricted blood flow. The fatty acid composition of the membrane lipid is important for membrane fluidity, this is mainly attributed to unsaturated fatty acids which are responsible for decreasing the order of membrane lipids thereby decreasing viscosity. At extremely low temperatures, organisms with low concentration of unsaturated fatty acids would freeze cell membranes. That's why antarctic fishes have higher levels of unsaturated fatty acids.
ecosystem:
Living and Nonliving Things in the Ecosystem. Ecosystems -- biological communities -- include living organisms like animals, plants, insects and bacteria, as well as nonliving components like rocks, soil, water and sunlight.
Answer: Microorganism activity affects soil acidity and the amount of organic matter in soil. It also affects the nutrient and mineral levels in soil as well as soil structure.
Explanation: