Concept 6.3: The eukaryotic cell’s genetic instructions are housed in the nucleus and carried out by the ribosomes

Flashcards from Concept 6.3 of Pearson's Campbell Biology, Twelfth Edition.

Nucleus

Organelle in eukaryotic cells that contains most of the DNA, which is used by ribosomes to make proteins

• One of the most conspicuous organelles

• Separated from the cytoplasm by the nuclear envelope

Nuclear envelope

A double membrane that separates the nucleus from the cytoplasm

Nuclear lamina

Proteins within the nuclear envelope that maintain the shape of the nucleus

Nuclear matrix

A framework of protein fibers throughout the interior of the nucleus

Chromosomes

Discrete units of DNA containing one DNA molecule associated with proteins called chromatin that condenses to form chromosomes during cell division preparation

Nucleolus

Site located within the nucleus for ribosomal RNA (rRNA) synthesis

Ribosomes

Complexes of ribosomal RNA and protein that build protein in the cytosol and on the rough endoplasmic reticulum or nuclear envelope

Free ribosomes

Ribosomes that produce proteins in the cytosol

Bound ribosomes

Ribosomes that produce protein on the outside of the endoplasmic reticulum or on the nuclear envelope