Hi hope I can help, I think the answer isB
<h2>Mitotic Cell Cycle</h2>
Explanation:
a. Cytochalasin: an inhibitor of actin microfilament
- Cytokinesis is the process by which cytoplasm is divided into two cells hence generation of two daughter cells
- In animal cells the division of cytoplasm starts with the assembly of contractile ring
- Contractile band consists of actin and myosin and catalyze cleavage furrow formation
- Cytochalasin is a drug that blocks the polymerization of actin filament
- When cytochalasin is added dividing cell fails to undergo in cytokinesis due to defective assembly of contractile band
b. Colchicine: an inhibitor of microtubule formation
- Colchicine tightly binds with free tubulin dimer and prevents its polymerization
- In this case mitotic spindle apparatus do not assemble and cells unable to do partitioning of chromosomes into two groups
- Thus cell division is arrested
c. Aphidicolin: an inhibitor of DNA Polymerase activity
- Aphidicolin is used to induce cell cycle arrest via specific inhibition of DNA Polymerase α
- It blocks the cell cycle at early synthesis(S) phase
d. Emetine: an inhibitor of ribosome activity
- It blocks the protein synthesis in eukaryotic cells by binding to small subunit(40 S) of ribosomes
- It interferes with the synthesis and activities of DNA and RNA
Transcription is the process by which RNA (nucleic acid that is responsible for transferring genetic information from DNA ) is synthesized from the genetic information contained in the coding regions of DNA. Therefore, a copy of complementary RNA and antiparallel to the DNA sequence that was transcribed is obtained. Normally organism synthesize RNA by a reaction catalyzed by RNA polymerases (they are enzymes that are involved in the process of DNA replication).
Transcription occurs in three steps: initiation, elongation and termination.
Initiation: Is the beginning of transcription. It occurs when the RNA polymerase enzyme binds to a region of a gene called a promoter. This tells the DNA to unwind so that enzyme can 'read' the bases in one of the strands of DNA. The enzyme is now ready to create a strand of mRNA (it is a single stranded RNA molecule, complementary to one of the DNA strands of a gene) with a complementary base of bases.
Elongation: Is the addition of nucleotides to the mRNA strand. The RNA polymerase reads the unwound strand of DNA and builds the mRNA molecule, using complementary base pairs. THere is a brief moment during this process when the new RNA molecule is bound to the unwound DNA. During this process, an adenine in the DNA binds to an uracil in the RNA.
Termination: Is the term of transcription and occurs when RNA polymerase crosses a termination sequence in the gene. The mRNA strand is complete and separated from the DNA.
Answer:
when it rains the soil will observe water that water is observed by roots of plants. the plants will take sun light to prepare it's food if water is so much it releases in form of water vapour the near the plants will cool down due to this moist air