Nicotine on direct application in humans causes irritation and burning sensation in the mouth and throat, increased salivation, nausea, abdominal pain, vomiting and diarrhea. Predominant immediate effects consist of increase in pulse rate and blood pressure. Nicotine also causes an increase in plasma free fatty acids, hyperglycemia, and an increase in the level of catecholamines in the blood. There is reduced coronary blood flow but an increased skeletal muscle blood flow. The increased rate of respiration causes hypothermia, a hypercoagulable state, decreases skin temperature, and increases the blood viscosity.
For amphetamine the immediate effects are quicker reaction times, feelings of energy/wakefulness, excitement, increased attentiveness and concentration, feelings of euphoria. Side effects of amphetamines can include heart palpitations, dry mouth, headache, hostility, nausea, cognitive impairment, severe anxiety, lack of appetite, teeth grinding, dizziness, increased heart rate, heart palpitations, rapid breathing rate, hypertension (high blood pressure), increased body temperature, erectile dysfunction, irregular heartbeat.
Cocaine causes a short-lived, intense high that is immediately followed by the opposite intense depression, edginess and a craving for more of the drug the side effects are Loss of appetite increased heart rate, blood pressure, body temperature, contracted blood vessels increased rate of breathing, dilated pupils, disturbed sleep patterns, nausea, hyperstimulation, bizarre, erratic, sometimes violent behavior hallucinations, hyperexcitability, irritability, tactile hallucination that creates the illusion of bugs burrowing under the skin, intense euphoria, anxiety and paranoia, depression, intense drug craving, panic and psychosis, convulsions, seizures and sudden death from high doses (even one time)
During DNA Replication, the DNA molecule unzips itself so that there are two free strands of DNA. Both of those strands then create new complementary strands of DNA. Thus every subsequent generation of DNA uses one of the parent cell's strand of DNA as a template, which is why DNA replication is said to be semi-conservative. Hope this helped!
Transcription is the first process that occurs in the expression of a gene. It involves the synthesis of a mRNA molecule from a DNA template. The DNA molecule, which is located in the nucleus of an eukaryotic cell, is bound to by an enzyme called RNA polymerase in order to synthesize an mRNA molecule/strand.
RNA polymerase synthesizes a mRNA molecule using complementary base pairing rule i.e. Uracil base (U) is synthesized when Adenine (A) is read, Adenine when Thymine (T) is read, Guanine (G) when cytosine (C) is read, Cytosine when guanine is read. These nucleotide bases are then joined together via chemical bonding.
In a nutshell, RNA polymerase catalyzes the formation of a bond between the backbone sugar of one nucleotide base to the backbone phosphate of another nucleotide base in the metabolic process of TRANSCRIPTION.
