T cells undergo positive selection in the thymus, which means they ________
A) develop surface antigen receptors
B) die and macrophages phagocytize them
C) remain alive but unresponsive
D) react against self antigens
E) multiply and form clones of identical T cells
E
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The chief force pushing water and solutes out of the blood across the filtration membrane is ________
A) the ionic electrochemical gradient B) glomerular hydrostatic pressure (glomerular blood pressure) C) protein-regulated diffusion D) the size of the pores in the basement membrane of the capillaries
The ICF contains about ____ of the total water of the body
a. 1/10 b. 1/4 c. 1/2 d. 2/3 e. 5/6
Describe the distribution of total blood volume in the body
A) The volume is divided into the systemic venous system (13%), systemic arterial system (64%), in the heart (7%), pulmonary circulation (9%), and systemic capillaries (7%). B) The volume is divided into the systemic venous system (64%), systemic arterial system (13%), in the heart (7%), pulmonary circulation (9%), and systemic capillaries (7%). C) The volume is divided into the systemic venous system (20%), systemic arterial system (20%), in the heart (20%), pulmonary circulation (20%), and systemic capillaries (20%). D) The volume is divided into the systemic venous system (75%), systemic arterial system (5%), in the heart (5%), pulmonary circulation (5%), and systemic capillaries (10%). E) The volume is divided into the systemic venous system (50%), systemic arterial system (37%), in the heart (7%), pulmonary circulation (3%), and systemic capillaries (3%).
What is the purpose of surfactant that lines each alveolus?
A. Gives the lungs their elasticity B. Increases the surface tension of water C. Keeps the alveoli from collapsing