1. Osmosis is a form of passive transport. Which defines osmosis?
A. the movement of water across a semipermeable membrane up a concentration gradient from low to high, using energy
B. the movement of water across a semipermeable membrane down a concentration gradient from high to low, using energy
C. the movement of water across a semipermeable membrane down a concentration gradient from high to low, using no energy
D. the movement of water across a semipermeable membrane up a concentration gradient from low to high, using no energy
2. Endocytosis and exocytosis are forms of active transport. What is active transport?
A. the movement of molecules down a concentration gradient from high to low, using no energy
B. the movement of molecules up a concentration gradient from low to high, using no energy
C. the movement of molecules down a concentration gradient from high to low, using energy
D. the movement of molecules up a concentration gradient from low to high, using energy
3. What does it mean for an environment to be isotonic?
A. The concentration of solute is greater in the environment than inside the cell
B. The concentration of solute in the environment and the concentration inside the cell are at equilibrium.
C. The concentration of solute is greater inside the cell than in the environment.
D. The concentration of solute in the environment is different from the concentration inside the cell.
4. Cells dispose of large waste molecules through a process called
A. exocytosis.
B. endocytosis.
C. osmosis.
D. diffusion.
5. A cell is dropped into a saltwater solution and shrivels up. You infer that, compared to the cell, the type of saltwater solution is
A. hypertonic.
B. isotonic.
C. hypotonic.
D. tonic.
1. C. the movement of water across a semipermeable membrane down a concentration gradient from high to low, using no energy (the correct definition of osmosis)
2. D. the movement of molecules up a concentration gradient from low to high, using energy (the correct definition of active transport)
3. B. The concentration of solute in the environment and the concentration inside the cell are at equilibrium. (isotonic means that the concentration of solute is the same inside and outside the cell)
4. A. exocytosis. (cells dispose of large waste molecules through exocytosis)
5. A. hypertonic. (if the cell shrivels up, it means that it lost water, indicating that the saltwater solution has a higher concentration of solutes compared to the inside of the cell)
1. The first step in attempting to factor the expression x^2−7x+10is to write out all of the factor pairs of the constant term. Which of the following is the complete list of factor pairs for the constant term in this expression?
A. −1 and 7, 1 and −7
B. 1 and 10, 2 and 5, −1 and −10, −2 and −5
C. 1 and 9, 2 and 8, 3 and 7, 4 and 6, 5 and 5
D. 1 and 10, 2 and 5
2. Factor x^2+5x+6
A. (x+1)(x+6)
B. (x+3)(x+2)
C. (x+5)(x+1)
D. (x+1)(x+5)
3. Which of the following is factorable?
A. X^2+3x−5
B. X^2+4x+4
C. X^2+5x+5
D. X^2+2x−4
4. Where n is an integer, if the expression x^2+nx+ 4 is factorable, which of the following is a possible value of n)
A. 2
B. -5
C. 3
D. -3
5. Nathan is attempting to factor the expression x^2+13x+12 He writes out the following factor pairs of 12 and concludes that the expression is not factorable. Is he correct? Explain.
2 and 6
3 and 4
A. Nathan is incorrect. He forgot to include the factor pair 1 and 12. If he had done this, he would have found that the expression is factorable.
B. Nathan is correct. None of the factor pairs have a sum of 13, so the expression is not factorable.
C. Nathan is correct. The expression is not factorable since the coefficient on the middle term is greater than the constant term.
D. Nathan is incorrect. He forgot to include the negative factor pairs, such as −3 and −4. If he had done this, he would have found that the expression is factorable.
1. B. 1 and 10, 2 and 5, −1 and −10, −2 and −5 (the complete list of factor pairs for the constant term 10)
2. B. (x+3)(x+2) (the factored form of x^2+5x+6)
3. D. X^2+2x−4 (the only expression in the options that can be factored)
4. A. 2 (since the sum of the factors of 4 is 2, and the sum of the factors should be equal to the coefficient of the middle term in a factorable expression)
5. B. Nathan is correct. None of the factor pairs have a sum of 13, so the expression x^2+13x+12 is not factorable.
1. Answer: C. the movement of water across a semipermeable membrane down a concentration gradient from high to low, using no energy
2. Answer: C. the movement of molecules down a concentration gradient from high to low, using energy
3. Answer: B. The concentration of solute in the environment and the concentration inside the cell are at equilibrium.
4. Answer: A. exocytosis.
5. Answer: A. hypertonic.