Answer: The correct answer is- A. Chromosome numbers vary widely.
Chromosome can be described as thread like structure that is composed of DNA ( deoxyribonucleic acid) and possesses genes ( segment of DNA coding for a particular protein) on it.
Eukaryotic cells ( such as plant cell, animal cell) have variable number of chromosomes.
For instance, human beings have 23 pairs of chromosomes whereas it is different in plants depending on the species.
Thus, A) is the right answer.
Colony, cell is the answer also u can use quizlet to help you find the answers
Answer: cellular membrane: The cell membrane, also called the plasma membrane, is found in all cells and separates the interior of the cell from the outside environment. The cell membrane consists of a lipid bilayer that is semipermeable. The cell membrane regulates the transport of materials entering and exiting the cell.
Explanation:
passive transport Passive transport is a type of membrane transport that does not require energy to move substances across cell membranes. Instead of using cellular energy, like active transport, passive transport relies on the second law of thermodynamics to drive the movement of substances across cell membranes.
Definition: "Copying of information from DNA to RNA which exit nucleus is known as transcription"
Explanation: Transcription is a vital process for living organisms, because it is a staring point for protein synthesis. It occurs inside the nucleus and is carried out by RNA polymerase enzyme. In eukaryotes RNA pol is of three types: these are RNA Pol 1, RNA Pol 2, and RNA Pol 3. In prokaryotes it is of only one type.
Steps in transcription: Transcription consists of three main steps
1. Initiation: In this step RNA pol attach to DNA template at 5 prime end in the promoter region to start the formation of complementary strand of RNA. In prokaryotes there is a region called
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Pribnow box, with the </span>consensus sequence<span> TATAAT present about 10 base pair away from site that serves as a transcription initiation. In eukaryotes the promoter region is more complex it contain activator and enhancer.
2. Strand elongation: </span><span>Once transcription is initiated, the DNA double helix unwinds and RNA polymerase reads the template strand, adding nucleotides to the 3′ end of the growing chain.
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3. Transcription Termination:
Terminator sequences are found close to the ends of non-coding sequences. Before termination polyadenylation occurs. <span>
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