A wind instrument is a musical instrument that contains some type of resonator (usually a tube), in which a column of air is set into vibration by the player blowing into (or over) a mouthpiece set at or near the end of the resonator. The pitch of the vibration is determined by the length of the tube and by manual modifications of the effective length of the vibrating column of air. In the case of some wind instruments, sound is produced by blowing through a reed; others require buzzing into a metal mouthpiece.
Ostrich eggshell is composed of 96% crystalline calcite and 4% organic material, mostly proteins. The thickness is made up of three different layers that vary in structure and thickness. The hardness of the shell is 3 on the Mohs scale. Pretty solid!
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Explanation:The Photosystems are the functional centers of photosynthesis. The pigments, such as chlorophyll, in the photosystems absorb light energy, which excites electrons. These electrons are transferred to electron-accepting molecules, eventually producing ATP and NADPH.
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In natural environments, horses typically live in relatively stable social units. Horses live in herds so that they are able to fulfil their basic needs, which are to avoid danger or harm, and to reproduce successfully and bring up healthy foals.
