Answer:
The correct answer will be-
1. Nucleosomes
2. Chromatin
3. Sister chroamtid
4. Centromere
Explanation:
The DNA is a very long molecule which if has to be passed on to the daughter cell as it is will cause problems. So, to reduce problems a cell form tightly packed structure of DNA so that they can be passed easily to the daughter cell.
The packaging of DNA begins with the wrapping of the DNA around histone proteins which forms the 11 nm basic structural units called nucleosomes. The nucleosomes start condensing each other and form 30 nm structure chromatin fibres.
The chromatin fibres undergo replication during S phase which produces an exact copy of the chromatin called sister chromatids bound to each other at a central point called centromere which helps the separation of the chromatids during M phase.
Answer:
D-DNA molecule
Explanation:
The process of copying the sequence of DNA nucleotide sequences to the mRNA is called Transcriptions. It is the first stage in gene expression for protein synthesis, and<u> it involves the unwinding of the DNA double strands molecules by enzyme</u><u> </u>DNA Helicase into two free strands,(by melting the hydrogen bonds between organic bases), a process initiated by the binding of enzymes RNA Polymerase to the promoter sites on the DNA template; the alignment of the mRNA nucleotides on the single DNA template strands in 3'-5 direction; the formation of hydrogen bonds between the organic bases of the template DNA and that of the messenger RNA single strands,( and phosphodiesterbonds within RNA nucleotide ), to form DNA-RNA complex.
The copying is done in complimentary anti parallel fashion;5'-3' prime. direction.
The hydrogen bonds, between the bases DNA-RNA complexes breaks,and the releases the mRNA which exists through the nuclear pores.Thus this <u>leads to copying of the the coded messages as seqeunce of DNA , from the DNA to the mRNA for gene expressions.</u>
<span>Epithelial cells in the stomach require the use of coupled transport to make gastric acid. They use hydrogen potassium ATPase, which is an electroneutral pump, and exchanges potassium for hydronium in order to produce the gastric acid.</span>
The answer is B (speed up chemical reactions).
Notchochord, morphology, chordates
