<span>Stem
cells develop into different types of cells as an organism grows. They also act
as internal repair systems. They divide without limit so as to replenish other
types of cells as long as the concerned organism is still alive. Stem cells
that develop to form either B cells or NK cells are normally found in the bone
marrow.</span>
Answer: Lk for this plasmid = 47
Explanation:
The formula to compute Lk is given by :-
Topological Linking Number (Lk): Twist (Tw) + Writhe (Wr)
Given: A plasmid 41 twists and 6 right handed writhes.
i.e. Twist (Tw) = 41 , Writhe (Wr) = 6
Then, Topological Linking Number (Lk) for this plasmid : = 41+6
= 47
Hence, the Lk for this plasmid = 47
Answer: The cell is eukaryotic because it has chloroplasts. A scientist is studying a cell and can clearly see that it has ribosomes and mitochondria.
Explanation:
"<span>The bacteria can cut the viral DNA at its specific restriction site but protect their own chromosomal DNA by modifying its bases and blocking the restriction enzyme" is the one explanation to the statement given in question. The correct option among all the options that are given in the question is the second option.</span>
Answer:
Option (A)
Explanation:
The Precambrian represents the time period, right from the beginning of the earth to about 540 million years back. It is divided into 3 parts, namely the Hadean, the Archean and the Proterozoic. Throughout this geological time, vast changes have taken place on earth. The first life forms of about 3.8 billion years old, that existed on earth were the simple unicellular organisms, whose traces were only found at some particular places. These organisms were very small and are comprised of soft bodies, so they were affected by the earth's dynamic processes. The organisms in order to get fossilized must contain hard parts. Due to the presence of soft bodies, the organisms were not fossilized and so it took a long time to demarcate that the late Precambrian organisms were animal-like life.
hence, the correct answer is option (A).
