Honors Bio Ch 4

Microscopy

The use of microscopes to view small organisms and details of biological samples not visible to the naked eye.

Animalcules

Tiny living organisms discovered by van Leeuwenhoek within a droplet of water.

Light Microscopy

Uses light to view small, usually living organisms or slices of larger specimens, often requiring staining.

Electron Microscopy

Uses electron beams to examine samples, providing better magnification and detail.

Scanning EM

A type of electron microscopy that reveals the surface features of specimens.

Transmission EM

A type of electron microscopy that examines slices of specimens to show internal details.

Cell Theory

The theory stating that all living things are made up of cells, the basic unit of life, and that new cells arise from existing cells.

Genome

The complete set of genes or genetic material present in a cell or organism.

Prokaryotes

Organisms with a single circular chromosome and no membrane-bound nucleus.

Eukaryotes

Organisms with multiple linear chromosomes contained within a membrane-bound nucleus.

Cytoplasm

The material within a cell, excluding the nucleus, which includes organelles and the cytosol.

Plasma Membrane

The boundary of a cell composed of a phospholipid bilayer that regulates what enters and leaves the cell.

Fluid Mosaic Model

A model describing the plasma membrane as a dynamic structure where proteins float in or on the fluid lipid bilayer.

Nuclear Envelope

The double membrane that surrounds the nucleus, perforated by nuclear pores.

Rough ER

Endoplasmic reticulum studded with ribosomes, involved in protein synthesis and processing.

Smooth ER

Endoplasmic reticulum lacking ribosomes, involved in lipid production and detoxification.

Golgi Apparatus

A series of flattened membrane-bound pouches responsible for modifying, packaging, and shipping proteins.

Vesicles

Membrane-bound transport structures that carry materials within the cell.

Lysosomes

Membrane-bound organelles containing hydrolytic enzymes for breaking down biomolecules.

Endomembrane System

A group of eukaryotic organelles that share and exchange membranes.

Mitochondria

Organelles that perform cellular respiration, converting food molecules into energy.

Chloroplasts

Organelles that conduct photosynthesis, converting light energy into chemical energy.

Cytoskeleton

A network of protein fibers that provide structure and shape to cells and assist in cellular movement.

Cell Walls

Rigid outer layers of cells in plants, fungi, and certain protists that provide support and protection.

Extracellular Matrix

A network of proteins and fibers outside animal cells that provides structural and biochemical support.

Endosymbiotic Theory

The theory that mitochondria and chloroplasts originated from ancient prokaryotic cells that were engulfed by ancestral eukaryotic cells.