1. You design an experiment to test the effectiveness of a new fertilizer. Which of the following factors would be considered a dependent variable?

A. The type of fertilizer used
B. The size and age of the plants
C. The amount of plant growth observed
D. The cost of the fertilizer per unit

Correct answer: C

Rationale: The dependent variable is the factor that is being measured or observed in an experiment. In this case, the amount of plant growth observed is the variable that is being influenced by the independent variable, which is the type of fertilizer used. The size and age of the plants (option B) could potentially be controlled variables, while the type of fertilizer used (option A) is the independent variable being tested. The cost of the fertilizer per unit (option D) is not directly related to the plant growth being measured in this experiment.

2. What is the function of a cell wall?

A. To provide structural support for the cell
B. To transport substances in and out of the cell
C. To synthesize proteins and lipids
D. To store genetic material

Correct answer: A

Rationale: Rationale: The cell wall is a rigid layer that surrounds the cell membrane in plant cells, fungi, and some bacteria. Its main function is to provide structural support and protection for the cell, helping maintain the cell's shape and preventing it from bursting or collapsing. The cell wall also allows for the passage of water, ions, and other molecules in and out of the cell. Options B, C, and D are incorrect because those functions are typically carried out by other cellular structures such as the cell membrane, ribosomes, and nucleus, respectively.

3. The major site for nutrient absorption in the digestive system is the:

A. Mouth
B. Stomach
C. Small intestine
D. Large intestine

Correct answer: C

Rationale: The correct answer is C: Small intestine. The small intestine is the major site for nutrient absorption in the digestive system. It is where most of the digestion and absorption of nutrients from food takes place. The small intestine has villi and microvilli that increase its surface area, allowing for efficient absorption of nutrients like sugars, amino acids, and fatty acids into the bloodstream. The mouth is primarily responsible for mechanical digestion through chewing, while the stomach's main function is to break down food with enzymes and acids. The large intestine mainly absorbs water and electrolytes, with minimal nutrient absorption.

4. What type of energy is stored in food?

A. Mechanical energy
B. Kinetic energy
C. Chemical potential energy
D. Thermal energy

Correct answer: c

Rationale: Food stores energy in the form of chemical potential energy, which can be released during metabolic processes.

5. What is the scientific study of the relationships between organisms and their environment?

A. Zoology
B. Botany
C. Ecology
D. Genetics

Correct answer: C

Rationale: Rationale: A) Zoology is the scientific study of animals. B) Botany is the scientific study of plants. C) Ecology is the scientific study of the relationships between organisms and their environment, including the interactions between living organisms and their physical surroundings. D) Genetics is the scientific study of genes, heredity, and variation in living organisms, which is not directly related to the relationships between organisms and their environment.