Domain Eukarya

Domain Eukarya

Comprises all organisms composed of eukaryotic cells, characterized by complex cellular organization.

Membrane-Bound Nucleus

A distinct compartment within eukaryotic cells containing the organism's genetic material organized into linear chromosomes.

Organelles

Specialized, membrane-bound structures within eukaryotic cells, such as mitochondria, endoplasmic reticulum, Golgi apparatus, and lysosomes.

Cellular Size

Eukaryotic cells typically range from approximately $10 \, \text{µm}$ to $100 \, \text{µm}$ in diameter, much larger than prokaryotic cells.

Cell Division

Eukaryotes reproduce cellularly through mitosis (asexual division) and meiosis (sexual reproduction).

Ribosomes

Eukaryotic cells contain $80S$ ribosomes in the cytoplasm, made of $60S$ and $40S$ subunits, distinct from prokaryotic $70S$ ribosomes.

Protista

A kingdom of unicellular or simple multicellular organisms, including protozoa, algae, and slime molds.

Fungi

Heterotrophic organisms that absorb nutrients from their environment, possessing cell walls made of chitin; examples include yeasts and mushrooms.

Plantae

Multicellular, autotrophic organisms capable of photosynthesis, with cell walls composed of cellulose and chloroplasts with chlorophyll.

Animalia

Multicellular, heterotrophic organisms that ingest other organisms for nutrition and lack cell walls; examples include invertebrates and vertebrates.

Endosymbiotic Theory

Explains the evolution of eukaryotic cells from ancestral prokaryotic hosts through the engulfment of aerobic bacteria (mitochondria) and cyanobacteria (chloroplasts).