The correct answer is<span> a. Volcanic glass
Volcanic glass is also known as Obsidian. It is formed when lava cools down too rapidly and crystals grow minimally, without grains.</span>
The Prostate gland
The prostate is a walnut-sized organ that surrounds the
first part of the urethra. It is located between the bladder and the penis. Semen
is formed by the prostate by combining a thick white fluid it initially produced
with the sperm from the testicles. It also produces an antibiotic protein known
as prostate-specific antigen (PSA) that changes the semen into liquid.
<span>They are mechanoreceptors that detect pressure, and are found in the skin and also in joints and tendons. Naked nerve endings lie in the centre of the corpuscle surrounded by concentric layers of connective tissue separated by viscous gel.
Looks like an onion.
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