In dna, adenine is always paired with
a cytosine.
b guanine.
c thymine.
d uracil.

Which of the following is an example of a tissue on the digestive system a.the stomach b.smooth muscle that lines the stomach c.nerve cells in the stomach d. enzyme molecules in the stomach

This is an active transport mechanism by which cells pump sodium and potassium ions against the concentration gradient

True or false: (a) the strings of little red dots represent carbohydrates. (b) the model is called a bilayer because there are two main types of molecules present, lipids and proteins. (c) the many black lines represent amino acid tails. (d) this model shows membrane transport. (e) the blue ovals are hydrophobic. (f) the blue ovals represent phospholipid heads.