In order to answer why the cell would need aquaporins when the plasma membrane is permeable to water, we need to understand the make-up of water and the cell membrane. The water molecule is polar with its H+ and OH- ions. Cell membranes are selectively permeable.
Anatomy of the Auricle. The auricle or pinna is a relatively large appendage on the side of the head. It is prominent in most people and plays a very important role in hearing â it directs sound waves into the ear canal. The auricle is composed of cartilage which is covered by skin.
The ulna is the longer and larger of the two bones, residing on the medial (pinky finger) side of the forearm. It is widest at its proximal end and narrows considerably at its distal end. At its proximal end, the ulna forms the hinge of the elbow joint with the humerus.natomy Explorer. 1  Bones of the Chest and Upper Back. 2  Bones of the Leg and Foot. 3  Bones of the Pelvis and Lower Back. 4  Elbow Joint. 5  Hand and Wrist. 6  Humerus. 7  Interosseous Membrane of the Arm. 8  Radius. 9  Shoulder Joint. 10  Ulna.