Characteristics and Functions of Eukaryotic Cells

Eukaryotes

Organisms with complex cells that have membrane-bound organelles and a nucleus.

Prokaryotes

Organisms with simpler cells that lack a nucleus and membrane-bound organelles.

Unicellular

Organisms consisting of a single cell.

Multicellular

Organisms composed of multiple cells.

Cholesterol

A type of lipid found in the membranes of eukaryotic cells.

Hopanoids

Sterol-like molecules found in some prokaryotic membranes.

Passive transport

Movement of substances across a cell membrane without the use of energy.

Active transport

Movement of substances against their concentration gradient, requiring energy.

Endocytosis

Process by which cells internalize substances from their external environment.

Cell wall

A rigid layer that provides support and protection to some cells, absent in animal cells.

Chitin

A structural polysaccharide found in the cell walls of fungi.

Cellulose

A polysaccharide that forms the primary component of plant cell walls.

Silica

A compound found in the cell walls of some algae.

Giemsa stain

A histological stain used for blood samples to identify certain pathogens.

Cilia

Hair-like structures that aid in movement and are present in eukaryotic cells.

Flagella

Long, whip-like structures that aid in cell movement.

Ribosome

Cellular structures responsible for protein synthesis.

Nucleus

The membrane-bound organelle that contains the cell's genetic material.

Nucleolus

A structure within the nucleus responsible for ribosome assembly.

Peroxisome

An organelle that breaks down hydrogen peroxide and other harmful substances.

Lysosome

An organelle that digests and recycles cellular waste.

Endoplasmic reticulum (ER)

An organelle involved in the synthesis of proteins and lipids.

Golgi apparatus

An organelle that modifies, sorts, and packages proteins and lipids for secretion.

Rough ER

Endoplasmic reticulum that has ribosomes attached, involved in protein synthesis.

Smooth ER

Endoplasmic reticulum that lacks ribosomes, involved in lipid synthesis and detoxification.