A liquid has a ph of 12. It is... A. an acid B. a base C. neutral

Which of the following descriptions of proteins are true? i. proteins can have different sequences of amino acids. ii. proteins can have different shapes. iii. proteins can have different numbers of amino acids. a. only i and ii are true. b. only ii and iii are true. c. only i and iii are true. d. i and ii and iii are all true. e. none are true statements

Select the correct answer. which term do biologists use to describe the average number of individuals of a species per unit area? a. carrying capacity b. population density c. minimal viable population d. survivability curve

Which of the following is the source of energy for photosynthesis? a.) glucose b.) chlorophyll c.) carbon dioxide d.) sunlight