Describe the mechanism by which a plant responds to gravity
What will be an ideal response?
Roots grow down and shoots grow upwards; this is called gravitropism. Root cells in particular contain dense starch granules (amyloplasts) that sink to the bottom of the cells, and may then cause auxin to move to the lower side of a root and block the elongation of these lower cells. Cells above continue to grow and elongate, causing the root to push downward and the shoot to grow upward.
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Describe phylogenomics and its contributions to phylogenetic relationships between protists and other
eukaryotes.
What will be an ideal response?Sympatric populations evolve reproductive isolation easily
a. true b. false
When growing conditions are not right, many bacteria form
A. Antibodies B. Acid C. Buds D. Endospores
Some cyanobacteria are capable of nitrogen fixation, a process that __________.
a. converts N2 to ammonia, making nitrogen available for incorporation into proteins and nucleic acids b. oxidizes nitrogen-containing compounds to produce ATP c. allows these bacteria to live in anaerobic environments d. removes soil nitrogen and returns N2 gas to the atmosphere e. s an essential part of the nitrogen cycle that extracts nitrogen trapped in mineral deposits and makes it available to organisms for their nitrogen metabolism