U mean y not what deaar!!
Answer:Valves stop blood flowing backwards
Explanation: Valve are flags of tissue that control the direction of the blood in our heart.,it prevent the backwards flow of blood. valves regulate blood from flowing back into the atria.The right and left atrio-ventricular valves prevent blood from flowing backwards into atria. When the ventricle is full,the valve prevent backwards flow of blood.
Answer:
Fatty acids are long chain carboxylic acids, they contain the carboxyl, COOH, functional group. The general formula for a fatty acid is R-COOH where R represents a long hydrocarbon chain. If the hydrocarbon chain, R, contains only single bonds between the carbon atoms, the fatty acid is said to be saturated.
During DNA replication, the two strands separate as the hydrogen bonds connecting the parent strands are broken by an enzyme called helicase. In the DNA molecule (double strand) complementary bases are joined by hydrogen bonds; that is; Adenine paired to thyamine and guanine to cytosine; during replication the enzyme helicase separates the double helix by breaking the hydrogen bonds between the complementary bases.
