Answer:
There is no actual way that the mantle could be...'exposed' or 'seen'. But scientists have managed to find multiple ways to analyze the mantle and it's actual existence by using multiple devices. The mantle is basically a 2,900 kilometers (1,802 miles) thick blocks of rocks and minerals underneath the crust(or the surface of the earth) , and makes up a whopping 84% of Earth's total volume.
Answer:
c. extensor digitorum
Explanation:
the extensor digitorum communis extends the phalanges, then the wrist, and finally the elbow. It tends to separate the fingers as it extends them. In the fingers, the extensor digitorum acts principally on the proximal phalanges, acting to extend the metacarpophalangeal joint.
The DNA polymerases are enzymes that create DNA molecules by assembling nucleotides, the building blocks of DNA. These enzymes are essential to DNA replication and usually work in pairs to create two identical DNA strands from one original DNA molecule. During this process, DNA polymerase “reads” the existing DNA strands to create two new strands that match the existing ones.
Every time a cell divides, DNA polymerase is required to help duplicate the cell’s DNA, so that a copy of the original DNA molecule can be passed to each of the daughter cells. In this way, genetic information is transmitted from generation to generation.
Before replication can take place, an enzyme called helicase unwinds the DNA molecule from its tightly woven form. This opens up or “unzips” the double stranded DNA to give two single strands of DNA that can be used as templates for replication.
DNA polymerase adds new free nucleotides to the 3’ end of the newly-forming strand, elongating it in a 5’ to 3’ direction. However, DNA polymerase cannot begin the formation of this new chain on its own and can only add nucleotides to a pre-existing 3'-OH group. A primer is therefore needed, at which nucleotides can be added. Primers are usually composed of RNA and DNA bases and the first two bases are always RNA. These primers are made by another enzyme called primase.
Although the function of DNA polymerase is highly accurate, a mistake is made for about one in every billion base pairs copied. The DNA is therefore “proofread” by DNA polymerase after it has been copied so that misplaced base pairs can be corrected. This preserves the integrity of the original DNA strand that is passed onto the daughter cells.

A surface representation of human DNA polymerase β (Pol β), a central enzyme in the base excision repair (BER) pathway. Image Credit: niehs.nih.gov
Structure of DNA polymerase
The structure of DNA polymerase is highly conserved, meaning their catalytic subunits vary very little from one species to another, irrespective of how their domains are structured. This highly conserved structure usually indicates that the cellular functions they perform are crucial and irreplaceable and therefore require rigid maintenance to ensure their evolutionary advantage.
Answer:
DNA rearrangment.
Explanation:
Genetics can be defined as the scientific study of hereditary in living organisms such as humans, animals and plants.
The human somatic cell is made up of 46 chromosomes which are sub-divided into 22 pairs of autosomes and a pair of sex chromosomes (X and Y). An autosome is one of the numbered chromosome that is typically not a sex chromosome.
On the other hand, sex chromosomes (X and Y) are responsible for determining the gender or sex of living organisms such as humans.
Deoxyribonucleic acid (DNA) is an organic complex-molecular structure found in all living organisms. It comprises of genes and is essentially the foundation block of all living organisms such as humans, animals and plants.
DNA rearrangment can be defined as a process which typically involves re-writing the informations contained within a Deoxyribonucleic Acid (DNA) into a Ribonucleic Acid (RNA) by enzyme RNA polymerase.
Hence, the ability of an individual to produce over a million different antibody molecules doesn't require the use of over a million different genes; rather, this wide range of antibody production is due to deoxyribonucleic acid (DNA) rearrangment.
Answer:
All four planets: Mercury, Venus, Earth and Mars are inner planets or also referred as terrestrial planets. Those are the planets orbiting closest to the Sun.
Earth is the largest of the Inner Planets, with a diameter of 12,756 km and Mercury is the smallest with a diameter of 4,878 km (3,031 miles). They have solid surfaces and thin/no atmospheres. Mercury is one of the densest planets in the Solar System. Venus is the brightest object we see in the sky, has a thick toxic atmosphere and is the hottest planet. Earth is the only planet that has liquid water.Mars surface contains iron-rich materials and has the most interesting terrain: the surface is very old and filled with craters.
Explanation:
