Biology 1023 Chapter 32 Questions and Solutions

Plants require carbon dioxide to produce sugar during photosynthesis. When a plant's stomata remains closed, which of the following can occur? - decrease in sugar production The xylem and phloem act much like the human circulatory system. Which of the following statements regarding the xylem and phloem is incorrect? - The phloem's only function is to transport sugars from the roots to the leaves. Gravitropism and phototropism are a result of a hormone called _______. - auxin Giant redwood and other woody plants contain cellulose and _______. - lignin In addition to water and sugar, plants require certain nutrients to grow. Certain bacteria present in fertile soil help plants obtain _______. - nitrogen Plant hormones, called gibberellins, are used in agriculture to do all of the following EXCEPT ___________. - promote abscisic acid Each fall, most deciduous trees produce vibrant colored leaves. Which of the following best explains why a leaf may turn yellow in the fall? - The green pigment in the leaves decreases, allowing the yellow pigment to stand out. Auxin is a hormone produced by plants that causes _______. - elongation of cells Which of the following is a method developed by plants to prevent self-pollination? - male and female reproductive organs located at different heights chemical barriers to fertilization of eggs Most plants are hermaphrodites, which means they ___________. - contain both male and female reproductive organs All of the following are pigments found in leaves EXCEPT _______. - chlorophyll anthocyanin xanthophylls carotene An oak tree that turns vibrant red in the fall is most likely a result of ___________. - sunny days increased sugar production trapped in the leaves high anthocyanin levels Certain "carnivorous" plants obtain their nitrogen from _______. - insects Which of the following is not an effect of auxin? - aerotropism