Cheat Sheet 2: Cells & Organelles

Nucleus

Contains DNA; coordinates cell activities.

Rough Endoplasmic Reticulum

Synthesizes and stores proteins; has ribosomes.

Cytoskeleton

Provides mechanical support and cell movement.

Extracellular Matrix

Binds adjacent cells; primarily collagen.

Smooth Endoplasmic Reticulum

Synthesizes lipids and steroid hormones.

Nucleolus

Site of ribosome synthesis (rRNA).

Microtubules

Composed of tubulin; supports cell structure.

Centrioles

Develop spindle fibers for cell division.

Cilia

Short extensions for cell movement.

Flagella

Thread-like extensions for cell motility.

Cytoplasm

Fluid area for metabolic activities.

Golgi Apparatus

Modifies and packages proteins for export.

Lysosomes

Break down waste and cellular debris.

Mitochondria

Produces ATP; site of fatty acid catabolism.

Peroxisomes

Break down fatty acids and detoxify.

Vacuoles

Membrane-bound vesicles for material transport.

Ribosomes

Made of rRNA; synthesize proteins.

Cholesterol

Regulates fluidity of the cell membrane.

Passive Transport

Movement without ATP; down concentration gradient.

Active Transport

Uses ATP to move substances against gradient.

Endocytosis

Process of engulfing substances into the cell.

Membrane Proteins

Facilitate transport across the cell membrane.

Junctions

Connect cells; includes tight and gap junctions.

Hypertonic

Higher solute concentration outside cell. Causes cell to shrivel

Hypotonic

Lower solute concentration (distilled water), causes cell to burst.