There are four fundamental states of matter:

• Solid
• Liquid
• Gas
• Plasma

In addition, there are several other non-classical and proposed states

While some people may have natural variations, the adult human body has 80 bones in the axial skeleton (the head, ribs, and spine), and 126 in the appendicular skeleton (the shoulder, hips, arms, and legs).  That makes 206 total bones.

BONUS TRIVIA: The number of bones you have changes over your lifetime.  Some bones fuse as they grow, and some don’t form until later in life, such as kneecaps, which usually develop around age 3.

Microwaves have the lowest frequency of the choices given.

When we talk about tectonic plates, we mean the sections into which the lithosphere is cracked. The surface of the Earth is divided into 7 major and 8 minor plates. The largest plates are the Antarctic, Eurasian, and North American plates.

Plates are on average 125km thick, reaching maximum thickness below mountain ranges. Oceanic plates (50-100km) are thinner than the continental plates (up to 200km) and even thinner at the ocean ridges where the temperatures are higher. Some plates are large enough to consist of both continental and oceanic crustal portions (e.g. the African or South American plates) whilst the Pacific Plate is almost entirely oceanic.

An ellipse has 2 focus points or foci. At any point in its orbit, a planet’s total distance from these 2 focus points stays the same.

Remember that all three types of RNA are synthesized from DNA molecules. Since DNA molecules can’t leave the nucleus, the synthesis of RNA has to occur in the nucleus.

On the other hand, proteins are synthesized in the cytosol and rough endoplasmic reticulum through translation. Proteins cannot be synthesized directly in the nucleus.

mRNA, or messenger RNA, is used as the template to synthesize proteins in translation. rRNA, or ribosomal RNA, make up the structural components of ribosomes. tRNA, or transfer RNA, facilitates the synthesis of proteins from mRNA. Though these molecules function in the cytosol, they are all synthesized in the nucleus.

Osteogenic cells are a type of stem cell that differentiate into osteoblasts, which allow bone to form. Eventually, osteoblasts will become enveloped in the bone matrix and differentiate into osteocytes. Osteoclasts have the opposite function as osteoblasts, and are responsible for the resorption of bone matrix. This releases calcium into the bloodstream by breaking down bone.

The question asks to point out the false statement. Everything on Earth is accelerated downwards by gravity, all the time, by 9.81ms2. Think of gravity as having a negative sign. When the ball is thrown up, acceleration is working against the velocity slowing the ball down. Their signs are opposite. But when the ball is falling back down to Earth, the velocity and acceleration have the same sign. So velocity and acceleration will not always have the same sign.

If gravity could be said to have a negative sign since it pulls everything downward, then an upward velocity would have a positive (and opposing sign). At the top of the trajectory when the ball’s upward velocity is finally overcome by gravity, the sign of the velocity becomes negative as it now points back down to Earth. So it is true velocity changes sign at the top.

Since the ball is caught at the same height, both the time up and time down are equal and it will be traveling at the same speed. Since gravity is the only force acting on it, the ball loses all its velocity on the way up and regains that exact amount by the time it reaches the height it started the journey. This also makes the time up equal to the time it falls. If the same force acts with the same strength (gravity) the entire time, why would either of these change?

About 715 of the Earth is covere4d by water.  96.5% of all the Earth’s water is contained within the oceans as salt water, while the remaining 3.5% is freshwater lakes and frozen water locked up in glaciers

While mostly solid, on a geological time scale, the mantle acts like a viscous fluid sometimes described as caramel.

Albedo is an expression of the ability of surfaces to reflect sunlight (heat from the sun). Light-colored surfaces return a large part of the sunrays back to the atmosphere (high albedo). Dark surfaces absorb the rays from the sun (low albedo)

The primary distinction between these two types of cells is that eukaryotic cells have a membrane-bound nucleus and prokaryotic cells do not. The nucleus is where eukaryotes store their genetic information.

The orographic effect occurs when air masses are forced to flow over high topography. As air rises over mountains, it cools and water vapor condenses. As a result, it is common for rain to be concentrated on the windward side of mountains, and for rainfall to increase with elevation in the direction of storm tracks.

The carrying capacity of a certain habitat is the maximum number of individuals that it can support. Population numbers are limited by resources such as space, food, and water. Current estimates of Earth’s carrying capacity are around 10 billion.

The formula is p=mv, or momentum (p) is equal to mass (m) times velocity (v).

The skin, or Integumentary System, makes up about 16% of your total mass.

Covalent bonds are produced when electrons are shared between atoms and are attracted by both atoms’ nuclei.