The four bases in DNA are adenine, cytosine, guanine, and thymine.
<span>These four are divided into two groups. The pyrimidines, the single-ring nitrogenous bases, is where thymine and cytosine is included. The purines, the double-ring nitrogenous bases, includes adenine and guanine. </span>
<span>Cytosine will only bond with guanine; they form three hydrogen bonds. Adenine will only bond with thymine forming two hydrogen bonds.</span>
Explanation:
When blood pressure drops too low, the rate of baroreceptor firing decreases. This will trigger an increase in sympathetic stimulation of the heart, causing cardiac output to increase.
The youngest would be the ones at the top and the oldest would be at the bottom. the oldest is B and the ones around it, as they get bigger get younger. hope this helps :)
1) A. Biological
2) D. Model
3) B. Cold
Answer:
Villi are finger-like projections.They increase the surface area of inner walls and helps alot in absorption of digested food.
Explanation:
