The speed of a sound wave depends upon the medium through which it travels. In general, sound travels faster through solids than through liquids or gases. Also, the denser the medium, the slower sound will travel through it. The same sound will travel at a different speed on a cold day than it would on a warm day.
Answer:
The skeletal system is vital in supporting the immune system because : Bones contain marrow, a porous material which creates both white and red blood cells. This replenishment of cells allows the body to fight and expel harmful bacteria, environmental toxins, foreign material e.t.c.
The white blood cells formed by the marrow are instrumental in isolating and destroying harmful particles (either on the site or in lymph nodes), or transporting them to the kidneys or bowels for excretion.
NOTE : Some people have marrow disorders which prevent their marrow from forming new cells; this is caused most often by cancer. Today, it is possible to transplant marrow from a healthy individual to a sick patient, and so help their bone marrow form new white and red blood cells to fight their sickness.
I hope it helps :)
The immune system is the bodies defense against invaders and is located in all body tissues with concentration in the mucosal surfaces and skin.
A 2nd-century hysteria was caused by the belief that the uterus could move freely within the body in search of fluid and cause specific symptoms depending on the areas the uterus was displaced to. Called the wandering womb disorder, the womb was believed to be a living thing within a living thing.
The right option is; dark-field microscope
A light microscope that makes the specimen appear light on a dark background is called a dark field microscope.
Dark field microscopes are light microscopes that are used in different ways to clearly view various specimens that are unstained, transparent, and hard to see using a light field unit. Dark field microscopes are very effective because they show the details of unstained and live samples. It is also very simple to use, and inexpensive to set up.
