1.1 Cell Theory

Cell Theory

A scientific theory which states that: 1. Living organisms are composed of cells; 2. The cell is the smallest unit of independent life; 3. Cells can only arise from pre-existing cells.

Emergent Properties

Functions present in multicellular organisms that are not present in individual component cells; they arise from interactions between individual cells.

Surface area to volume ratio

The ratio that is crucial in determining the limit on cell size; as a cell grows, volume increases faster than surface area.

Metabolism

The set of life-maintaining chemical reactions that occur within a cell.

Microscopes

Instruments used to view small objects; light microscopes use light and lenses, while electron microscopes use electrons for higher magnification and resolution.

Striated muscle

A type of muscle composed of fused cells that are multinucleated; presents a caveat to cell theory.

Giant algae

Unicellular organisms that can be very large in size, illustrating that cells can vary widely in dimensions.

Aseptate hyphae

Fungal structures that lack partitioning and have a continuous cytoplasm; another caveat to the traditional cell theory.

Metabolic requirements

The needs that a cell has to perform biochemical processes that support life, which must be fulfilled by material exchange.

Magnification

The process of enlarging the appearance of an object as viewed under a microscope.

Light microscopes

Microscopes that allow for viewing living specimens in natural color but have lower magnification and resolution compared to electron microscopes.

Electron microscopes

Advanced microscopes that use electrons to achieve high magnification and resolution, primarily used to view dead specimens.

Cellular Organization

The arrangement of cells into tissues, organs, and systems within multicellular organisms.