Which statement best describes homeostasis in a cell? A. Molecules are in equilibrium (balance) inside and outside the cell

B. Active transport causes molecules to move from low to high concentration the molecules are un-equal

C. Pathogens enter cells and infect those cells, causing them to malfunction

D. Cells do not maintain homeostasis with their external environments.

During sunny hours, a large amount of build up between the hours of 1: 00-5: 00 pm. a. ozone b. mercury c. lead d. sulfuric acid

How does pregnancy begin? a) a placenta forms in the uterus b) a sperm reaches an egg in the fallopian tubec) the blastocyst differentiates into two cell types d) contractions begin in the uterine wallapex

1. environmental factors, such as ph and temperature, can affect the function of an enzyme. a. true b. false 2. which of the following is an organic molecules (ex. vitamins) that an enzyme? a. coenzyme b. product c. active site d. substrate 3. how do enzymes effect the speed of a chemical reaction? a. they speed it up b. they slow it down c. they have no effect on the speed of a reaction 4. during a chemical reaction, an enzyme is used up so that it can only be used one time. a. true b. false 5. which of the following results from a chemical reaction that is catalyzed by an enzymes? a. active site b. product c. substrate d. coenzyme