Which statement concerning transmembrane proteins in the plasma membrane is false?
A. They extend all the way through the plasma membrane.
B. Some have carbohydrate chains and help form the glycocalyx.
C. They are more abundant than the phospholipids.
D. They may serve as channels that allow certain solutes to enter and leave the cell.
E. They may be carriers that transport substances from one side of the plasma membrane to the other.
C. They are more abundant than the phospholipids.
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The insertion of the anterior part of the frontalis muscle is the
A) temporal bone. B) epicranial aponeurosis. C) occipital bone. D) skin of the eyebrow and the bridge of the nose. E) coronoid process of the mandible.
Which is not a function of the kidneys?
A. Regulation of blood pressure B. Removal of wastes from the blood C. Regulation of erythrocyte production D. Regulation of lymphocyte production E. Regulation of acid-base balance
Which of the following statements about ATP is false?
A) ATP drives the transport of certain solutes (e.g., amino acids) across cell membranes. B) ATP activates contractile proteins in muscle cells so that cells can shorten and perform mechanical work. C) ATP provides the energy needed to drive energy-absorbing chemical reactions. D) ATP is a modified nucleotide. E) The phosphate groups of ATP are attached by high-energy hydrogen bonds.
During reabsorption in the proximal convoluted tubule, most of the amino acids, glucose, Na+ ions, K+ ions, and Ca2+ ions are removed from the tubular fluid by ________ mechanisms.
A. passive transport B. counter transport C. active transport D. osmotic