7.5 Proteins Learning Target: Explain the significance of polar and nonpolar amino acids. Outline the difference between fibrous and globular proteins.

Cytoplasmic Proteins ●Surrounded by water ●Polar amino acids side chains fold to the outside of the structure ●Non-polar amino acid side chains are protected on the inside of the structure

Membrane Proteins ●How does the structure of the cell membrane affect transmembrane proteins? ●Predict: Label hydrophilic heads of phospholipids, hydrophobic tails of phospholipids, polar amino acid region, and non-polar amino acid region.

Membrane Proteins ●Within the amphipathic membrane ●Polar amino acids in hydrophilic region (inner/outer surface) ●Nonpolar amino acids in hydrophobic core ●Polar amino acids lining channels so charged/polar molecules can pass through

Fibrous & Globular Proteins Fibrous ProteinsGlobular Proteins Long and narrowCompact and rounded Insoluble in waterSoluble in water Structure and supportEnzymes and transport KeratinHemoglobin CollagenCatalase