The protein fibers that provide an internal framework for a cell are called the:

An alternative membrane name for the skin is:

Keratin is the main protein fiber found in the stratum corneum, and its main function is to provide elasticity to the skin.

Hydrophilic solutes freely pass through the phospholipid bilayer of a plasma membrane.

Plasma membranes are generally impermeable to water.

The most metabolically active cells that produce keratin are located in the ______________.  The main function of keratin is to ________________.

Which of the following is NOT a true statement about hair or hair follicles?

Gristle covering the ends of bones is composed of this tissue, which is also found attached to most ribs:

This type of tissue lines the inside of the urinary bladder, which has to change size as urine is stored and later released.

Which is shed (sloughed off)?