Students in a biology class ran an experiment on a type of flowering plant. their goal was to find the optimal time in the plant's life for flowering. what time period will provide the most flowering plants? use table 1-1 to determine your answer. day number of plants flowering 2 6 4 12 6 18 8 22 10 8 a 8–9 days b 7–8 days c 5–6 days d 6–7 days

25) a student takes four samples of a white crystalline solid and places each in a well plate. on top of each sample, she carefully places 20 drops of clear mystery liquids a, b, c and d. her results for each well are: liquid a: the solid dissolves quickly. liquid b: the solid appears unchanged. liquid c: a brownish colored liquid is produced. liquid d: fizzing occurs and the well becomes warmer. in which well does a physical change occur?

Which image shows labeled organelles that are present only in plant cells?

Which is an advantage of having memory cells when a pathogen is encountered for a second time. a) the memory cells are what proliferate into clones of cells in response to the binding of an antigen. b) memory cells are vital to the primary immune response in that they immediately recognize pathogens even at the first encounter. c) memory cells are essentially effector cells that are short lived and attack antigens even without having a receptor specific to that antigen. d) it ensures that more lymphocytes with a receptor specific to a particular antigen will be present than in a host that had never encountered that pathogen.