Answer:
RNA polymerase binds to the promoter
Polymerase initiates RNA synthesis at the start point on the template strand
RNA polymerase moves downstream unwinding the DNA
RNA transcript is released and polymerase detaches from the DNA
The pre-RNA undergoes processing
Explanation:
The promoter is the specific DNA sequence that serves as a binding site for RNA polymerase. The enzyme RNA polymerase recognizes the promoter sequence and binds to it to begin the process of RNA synthesis. The process of RNA synthesis begins at the start site where the process of the unwinding of DNA duplex is initiated.
The unwinding separates the two DNA strands at the start site where RNA polymerase begins the process of synthesis of the new RNA strand. The newly formed RNA strand and RNA polymerase are released from the template strand after the termination of the process.
In eukaryotes, the primary RNA transcript undergoes the process of splicing of introns, the addition of poly-A tails and 5' cap which in turn transform it into the mature mRNA.
1. Paralysis that’s all I know I’m sorry
Answer:
The correct answer is 3: "<em>High levels of Ca2+ are expected to be found </em><em>within the sarcoplasmic reticulum</em>".
Explanation:
Muscular contraction is a highly regulated process that depends on free calcium concentration in the cytoplasm. Amounts of cytoplasmic calcium are regulated by <u>sarcoplasmic reticulum</u> that functions as a storage of the ion.
When a nerve impulse reaches the membrane of a muscle fiber, through acetylcholine release, the membrane depolarizes producing the entrance of calcium from <u>extracellular space</u>. The impulse is transmitted along the membrane to the sarcoplasmic reticulum, from where calcium is released. At this point, <em>tropomyosin is obstructing binding sites for myosin on the thin filament</em>. The calcium channel in the sarcoplasmic reticulum controls the ion release, that activates and regulates muscle contraction, by increasing its cytoplasmic levels. When <em>calcium binds to the troponin C</em>, <em>the troponin T alters the tropomyosin by moving it and then unblocks the binding sites,</em> making possible the formation of <em>cross-bridges between actin and myosin filaments.</em> When myosin binds to the uncovered actin-binding sites, ATP is transformed into ADP and inorganic phosphate.
Z-bands are then pulled toward each other, thus shortening the sarcomere and the I-band, and producing muscle fiber contraction.
It helps make and fix body tissue.
