True or false?

1. a scientist who performs an experiment has not predicted what the outcome of the experiment is going to be.
2. the control group and experimental groups are designed to be identical.
3. the independent variable is the variable that the experimenter changes in an experiment.
4. without enzymes, chemical reactions necessary for life would not occur at a rate sufficient to sustain life.
5. membranes are selectively permeable if they allow only certain substances to move across them.
6. water will diffuse out of a cell when the cell is placed in a hypertonic solution.
7. the transport of specific particles down their concentration gradient through a membrane by carrier proteins
is known as facilitated diffusion.
8. in active transport, energy is required to move a substance across a cell membrane.
9. exocytosis the cell rid itself of wastes.