Chapter 1-7: Cellular Organelles and Membrane Structure (Vocabulary Flashcards)

Vocabulary flashcards covering mitochondria, chloroplasts, endosymbiosis, DNA/ribosome structure, protein sorting, endomembrane system, ECM components, and membrane architecture.

Mitochondria

Semi-autonomous organelles with their own circular genome and ribosomes; main site of ATP production; inner membrane folds into cristae to increase surface area.

Chloroplast

Semi-autonomous organelle in plant cells with its own circular genome and ribosomes; site of photosynthesis; contains thylakoid membranes forming grana.

Semi-autonomous

Partially independent; organelles retain some genome and function but rely on the cell for materials.

Intermembrane space

The space between the outer and inner membranes of mitochondria (and chloroplast envelopes); site of some processes.

Cristae

Folds of the inner mitochondrial membrane that increase surface area for energy-transformation reactions.

Thylakoid

Membrane-bound sacs inside chloroplasts where the light-dependent reactions of photosynthesis occur.

Grana

Stacks of thylakoid membranes within chloroplasts.

Thylakoid lumen

The internal space inside the thylakoid membranes.

Mitochondrial genome

Circular DNA within mitochondria encoding a small set of essential genes; resembles bacterial genomes.

Chloroplast genome

Circular DNA within chloroplast encoding a small set of essential genes; resembles bacterial genomes.

Endosymbiosis theory

Hypothesis that mitochondria and chloroplasts originated from engulfed prokaryotes forming a symbiotic relationship.

Proteobacteria

Bacteria lineage ancestral to mitochondria (mitochondrial ancestors).

Cyanobacteria

Bacteria lineage ancestral to chloroplasts (photosynthetic).

Prokaryotic ribosomes

Ribosomes in mitochondria and chloroplasts resemble bacterial ribosomes in structure.

Binary fission

A division process used by mitochondria and chloroplasts to grow and reproduce, similar to bacteria.

Circular DNA

DNA in mitochondria and chloroplasts is circular, like bacterial chromosomes, unlike linear eukaryotic nuclear DNA.

Post-translational sorting

Proteins synthesized in the cytosol and then imported to mitochondria, chloroplasts, nucleus, or peroxisomes.

Co-translational sorting

Proteins are sorted and targeted to organelles during translation, often via the ER.

Endoplasmic reticulum (ER)

Membrane-bound organelle where synthesis of secretory and membrane proteins begins; site of co-translational sorting.

Golgi apparatus

Organelle where proteins are further processed, sorted, packaged, and sent to final destinations (lysosomes, vacuoles, plasma membrane, secretion).

Extracellular matrix (ECM)

Network outside the cell composed of proteins, proteoglycans, and glycoproteins that provides structure and signaling.

Proteoglycan

Core protein with glycosaminoglycan chains; highly negatively charged; binds water to form a protective, hydrated matrix.

Glycosaminoglycan (GAG)

Long, unbranched, negatively charged polysaccharides that attract water and resist compression.

Glycoprotein

Protein with attached carbohydrate chains; components of ECM or membrane proteins with carbohydrate modifications.

Glycolipid

Lipid with attached carbohydrate; part of ECM and plasma membrane giving cell recognition and stability.