Answer:
D
Explanation:
because the nucleus contains protons and neutrons.
Answer:
HBV (hepatitis B) is a viral infection that attacks the liver. It can cause acute or chronic disease and it is transmitted through contact of blood or other body fluids of an infected person.
<em>An infected person can be transmitted through birth, sharing of needles, sharing of common household personal hygiene items, direct contact with an open or bloody sore, or through sexual contact.</em>
It is a hidden treat because those who have hepatitis B can transmit it to another (blood/other body fluid); if they know they have it or not.
Acute hepatitis B is short-term (6 months after being exposed) and they can become immune and can not get infected again; but it can lead to chronic hepatitis B (depends on how healthy the person is).
Chronic hepatitis B can cause liver damage, cirrhosis, liver cancer, and death.
Explanation:
Answer:
<u>Stores DNA</u>
Explanation:
The nucleus controls all the activities of a cell. The chromatin contains the hereditary materials, DNA while the nucleolus is responsible for the manufacture of ribosomes.
Answer:
hey you!
Explanation:
Quartzite
Quartzite is a metamorphic rock formed when quartz-rich sandstone or chert has been exposed to high temperatures and pressures. Such conditions fuse the quartz grains together forming a dense, hard, equigranular rock. The name quartzite implies not only a high degree of induration (hardness), but also a high quartz content. Quartzite generally comprises greater than 90% percent quartz, and some examples, containing up to 99% quartz, and are the largest and purest concentrations of silica in the Earth's crust. Although a quartz-rich sandstone can look similar to quartzite, a fresh broken surface of quartzite will show breakage across quartz grains, whereas the sandstone will break around quartz grains. Quartzite also tends to have a sugary appearance and glassy lustre. The variety of colours displayed by quartzite are a consequence of minor amounts of impurities being incorporated with the quartz during metamorphism. Although quartzite can sometimes appear superficially similar to marble, a piece of quartzite will not be able to be scratched by a metal blade, and quartzite will not fizz on contact with dilute hydrochloric acid.
Texture - granular.
Grain size - medium grained; can see interlocking quartz crystals with the naked eye.
Hardness - hard.
Colour - variable - pure quartzite is white but quartzite exists in a wide variety of colours.
Mineralogy - quartz.
Other features - generally gritty to touch.
Uses - pure quartzite is a source of silica for metallurgical purposes, and for the manufacture of brick; as aggregate in the construction and roading industries; as armour rock for sea walls; dimension stone for building facings, paving etc.
New Zealand occurrences - northwest Nelson (Aorere).
