1. What is the main function of the large intestine?

A. Break down food
B. Absorb water
C. Secrete digestive enzymes
D. Store waste

Correct answer: B

Rationale: The correct answer is B: "Absorb water." The main function of the large intestine is to absorb water and electrolytes from the undigested food material that passes through it. This helps in the formation of solid waste or feces, which is then stored in the rectum until it is eliminated from the body. Breaking down food primarily occurs in the small intestine, while the large intestine focuses on reabsorbing water to prevent dehydration. Secreting digestive enzymes is mainly done by the pancreas and liver, not the large intestine.

2. Which property of a substance refers to its ability to be stretched into thin wires?

A. Conductivity
B. Viscosity
C. Ductility
D. Malleability

Correct answer: c

Rationale: Ductility refers to a substance's ability to be stretched into thin wires without breaking.

3. What happens to the kinetic energy of an object when its mass is doubled?

A. Kinetic energy remains the same
B. Kinetic energy halves
C. Kinetic energy doubles
D. Kinetic energy quadruples

Correct answer: c

Rationale: Kinetic energy is directly proportional to the square of an object's mass when its velocity remains constant.

4. Scientists compare the DNA of different organisms to understand evolutionary relationships. What is this type of evidence called?

A. Morphological evidence (comparing body structures)
B. Biochemical evidence (comparing molecules like proteins)
C. Geographic distribution evidence (where organisms live)
D. Genetic evidence (comparing DNA sequences)

Correct answer: D

Rationale: Rationale: A) Morphological evidence involves comparing body structures of organisms, which can provide information about evolutionary relationships based on physical similarities and differences. However, DNA comparison is a more direct and accurate method for understanding evolutionary relationships. B) Biochemical evidence involves comparing molecules like proteins, which can also provide insights into evolutionary relationships. However, DNA comparison is considered more reliable due to the direct relationship between DNA sequences and genetic information. C) Geographic distribution evidence refers to where organisms live and how their distribution may provide clues about evolutionary history. While this can be informative, it is not as direct or specific as comparing DNA sequences. D) Genetic evidence involves comparing DNA sequences of different organisms to understand their evolutionary relationships. DNA comparison is a powerful tool in evolutionary biology because it provides

5. You design an experiment to test the effect of temperature on plant growth. Which variable should you keep constant?

A. The type of soil used.
B. The amount of sunlight the plants receive.
C. The amount of water given to the plants.
D. The temperature variations being tested.

Correct answer: A

Rationale: In this experiment, the variable being tested is the effect of temperature on plant growth. To ensure that any observed changes in plant growth are due to temperature variations and not other factors, it is important to keep other variables constant. The type of soil used can significantly impact plant growth, so it should be kept constant to isolate the effect of temperature. Keeping the amount of sunlight and water constant would also help ensure that any differences in plant growth are due to temperature variations.

6. What type of waves require a medium (solid, liquid, or gas) to propagate?

A. Transverse waves
B. Longitudinal waves
C. Electromagnetic waves
D. Surface waves

Correct answer: B

Rationale: Longitudinal waves require a medium (solid, liquid, or gas) to propagate because the particles in the medium move parallel to the direction of the wave. Transverse waves, on the other hand, do not require a medium and can propagate through a vacuum. Electromagnetic waves also do not require a medium for propagation, as they consist of oscillating electric and magnetic fields. Surface waves are a combination of both longitudinal and transverse waves and also require a medium to propagate.