Discovery In 1928 it was discovered by Frederick Griffith in an experiment generally known as transformation.
Experiment
In his experiment he considered two strains of <em>streptococus pneumonia,</em> one was R-type which was non-virulent and cause no disease in mice, other was virulent and S-type which cause disease and at last death of mice.
This experiment was comprised of four steps which are as follow:
Step 1: First he injected living strain of S into mice, after sometime mouce died.
Step 2: He injected living strain of R into mice, the mice alive as he did not got any disease.
Step 3: He injected heat killed strain of S into mice and mice remain alive.
Step 4: He mixed living R strain with heat killed S strain and then inject into mice. As a result the mice died.
Conclusion: It was found that genetic material from heat killed S stain were transferred to living R (non-virulent) strain, as a result R become virulent and cause the death of mice.
Nitrogenous base DNA consists of four unique nucleotides that each contain one unique nitrogenous base—adenine (A), thymine (T), cytosine (C), or guanine (G).
The specific arrangement of these four bases within the DNA of each organism gives that organism its unique traits; here are the arrangements:
-<u>Adenine</u> is paired with <u>Thymine</u> (think of A for apple and T for tree)
-<u>Cytosine</u> is paired with <u>Guanine</u> (think of C for car and G for garage)
search "DNA base pairs" and go to images for better understanding
I just did this BTW. The correct answer is A.) Nuclear fusion is the correct answer. Nuclear fission is what we use today in nuclear power plants, a great deal of radioactive waste, the other are by products of this process. Nuclear fusion releases a great deal of energy with a little radioactivity, but the problem is ignition temperatures; but maybe someday.
B THEY RELEASED CARBON DIOXIDE, WHICH EVOLVING ANIMALS NEEDED.
Answer:
Increasing the alveolar ventilation rate will increase the partial pressure of oxygen in the alveoli.
Explanation:
Alveolar Ventilation rate is the rate of air flow in the alveoli of the lung during normal breathing. It is measured in milliliters of air per minute (mL/min). The alveolar ventilation rate is an important factor in determining the concentrations (partial pressures) of oxygen and carbon dioxide in the functioning alveoli.
A high rate of alveolar ventilation, would result in a rapid influx of oxygen-rich air and efflux carbon dioxide-filled air from the alveoli. This ultimately results in an increase in the concentration of oxygen and a decrease in the concentration of carbon dioxide within the alveoli.
Effects of alveolar ventilation on partial pressures of alveolar carbon dioxide and oxygen (PACO₂ and PAO₂)
If the alveolar ventilation rate is increased (and carbon dioxide production is unchanged), then the partial pressure of carbon dioxide in the alveoli, PACO₂ will decrease.
If the alveolar ventilation rate increases, then the partial pressure of oxygen in the alveoli, PAO₂ will increase.