Answer:
A. 17,100
Explanation:
The half life of carbon-14 is around 5,700 years. When the shell contains 50% of its original carbon-14, 5,700 years have passed. 25% means another 5,700 years have passed, meaning 11,400 years in total have passed. 12.5% means another 5,700 years have passed, meaning 17,100 years have passed in total.
Magnetic force - B.
Electrical force - A.
Gravitational force - D.
Contact force - C.
<h3><u>Explanation:</u></h3>
When a charge moves about its path, it produces a magnetic force around it. This magnetic field is perpendicular to the axis of movement of the charge and is directly proportional to the amount of charge, speed of the charge, and inversely proportional to distance between the charge and the point of measurement. Michael Faraday discovered this phenomenon.
Electrical force of attraction or repulsion is seen between the two charged bodies, or one charged body and one uncharged body which can induce charge to the uncharged body. The attraction or repulsion between the charged bodies are seen if the bodies are close enough, and this is called electrical force.
The gravitational force is also a non contact force that is seen between two bodies which is always attractive in nature and is seen between any two bodies.
A contact force like friction is a type of force that takes place only when two bodies are in contact with each other.
Answer:
D. Alternative splicing is the mechanism that produce complexity in the genes by splicing some of the protein coding part (exons) of a genes
Explanation:
There are certain splicing enhancers sites present in Exons which facilitiates the binding of RNA binding protein specifically SR protein family rich in Serine and Arginine residues. This SR protein will help in splicing of exons.
The significance of this type of mechanism is the ability of a cell to produce an isoform of protein which have retain their function.
This mechanism also help is diversity or in short in evolution.
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