7th Grade Life Science – Winter Benchmark Practice Flashcard

The best hypothesis is that more sunlight leads to taller plants due to its role in photosynthesis, directly linking sunlight to growth, unlike the other options which are more general or unrelated.

The independent variable is the factor that is changed in an experiment. In this case, the temperature of the environment is manipulated to observe its effect on mold growth, making it the independent variable.

Repeating the experiment many times increases reliability by ensuring that results are consistent and not due to random chance. This helps to confirm findings and reduces the impact of anomalies.

The graph indicates a positive correlation between aquatic insect numbers and oxygen levels, suggesting that higher oxygen levels support more aquatic insects. Thus, the best conclusion is that more aquatic insects are found where oxygen levels are higher.

The cell membrane controls what enters and leaves a cell by acting as a selective barrier, allowing certain substances to pass while blocking others. This is essential for maintaining the cell's internal environment.

The presence of chloroplasts, a cell wall, and a large vacuole indicates that the cell is a plant cell, as these structures are characteristic of plant cells and not found in bacterial, animal, or fungal cells.

The observation that cells divide to form new cells is fundamental to modern cell theory, which states that all living organisms are composed of cells and that all cells arise from pre-existing cells.

The correct sequence is Cell → Tissue → Organ → Organ system → Organism, as it progresses from the simplest unit (cell) to the most complex (organism), reflecting the hierarchical organization in biological systems.

A nerve cell, or neuron, is a specialized cell that transmits signals in the nervous system. It is not a complete organism, tissue, or organ system, but rather a cell that is part of a multicellular organism.