Answer:
Neurological signals sent from fear responses in an organism tell the cell to stop. The cell's DNA has been damaged somehow. The cell's DNA was replicated incorrectly.
Explanation:
All the three options given can cause checkpoint genes to interrupt cell division.
Checkpoint genes are transcription genes that control cell cycle and sense defects during cells processes like DNA replication, segregation e.t.c and create response till the defects is repaired in the DNA. The important of checkpoint is that it ensure enough nutrients are available to support for division, ensure that the DNA has not been damaged, ensure that cells DNA is copied correctly and make sure cells have enough RNA for their protein synthesis.
Checkpoints genes can interrupt cell division if the dna is damaged, Dna is copied incorrectly and neurological signal sent from fear responses in an organisms tell the cells to stop.
Answer:
Nitrogen thet cannot be used by organisms. C.
Explanation:
Free nitrogen is simply molecular nitrogen (N2). Nitrogen, in its molecular form, consists of two nitrogen atoms bound together with a tripple bond. Because it is very stable, N2 is typically nonreactive, and takes a lot of energy to break them apart. Among these are the amino acids necessary for life to begin and which are the building blocks DNA is made from. Basically, any nitrogen that is in an organic compound is considered “fixed” nitrogen and N2 is considered to be “free” nitrogen
Answer:
Explanation:
Transcription takes place in nucleus in the presence of the enzyme RNA polymerase.
During transcription, the code present in DNA gets transcribed into the code in mRNA. (messenger RNA)
RNA even though is a single stranded shows base pairing.
The pre-mRNA gets created from the DNA.
DNA has two strands, one of these strands acts as coding and another non coding strand.
The DNA shows base pairing with AGTC. [A-Adenine, G- Guanine, T-Thymine and C- Cytosine]
Whereas mRNA base pairing with AGUC. [ U- Uracil ]
Here in mRNA, instead of thymine, uracil gets paired.
According to base pairing of coding strand/sense strand of DNA, complementary bases pairs in 5'---->3' direction in mRNA.
The mRNA created looks exactly like the non-coding strand/sense strand of DNA except instead of thymine, uracil gets replaced.
The pre-RNA undergoes splicing, capping and tailing to form mature mRNA.
Answer:
Temperature changes can also contribute to mechanical weathering in a process called thermal stress. Changes in temperature cause rock to expand (with heat) and contract (with cold). As this happens over and over again, the structure of the rock weakens.
Explanation:
