下载APP
【单选题】
The physiologic function of the relatively slow conduction through the atrioventricular node is to allow sufficient time for（ ）
A.
Repolarization of the ventricles
B.
Venous return to the atria
C.
Contraction of the ventricles
D.
Runoff of blood from the aorta to the arteries
E.
Filling of the ventricles
举报
参考答案：
参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】Name the structure of the nephron that reabsorbs the most substances.（ ）
A.
Collecting duct
B.
Distal convoluted tubule
C.
Proximal convoluted tubule
D.
Glomerular capsule
E.
Loop of Henle
【单选题】The food with the most significant special dynamic effect is（ ）
A.
Dietary fiber
B.
Protein
C.
Fat
D.
Sugar
E.
Inorganic salt
【单选题】The main components of nerve cell action potential are（ ）
A.
Negative after-potential
B.
Local potential
C.
Positive after-potential
D.
Peak potential
E.
Threshold potential
【单选题】In the refraction system of the eye, the interface with the greatest refraction ability is（ ）
A.
Vitreo-retinal interface
B.
Posterior corneal surface -- aqueous humor
C.
Air -- anterior surface of cornea
D.
Posterior surface of lens -- vitreous body
E.
Aqueous humor -- anterior lens surface
【单选题】The components involving in the formation of the mucus-bicarbonate barrier are（ ）
A.
H+
B.
Na+
C.
C l-
D.
HCO3-
E.
K+
【单选题】Which of the following will decrease the rate of oxygen transfer between the alveolar air and the pulmonary capillary blood?（ ）
A.
Decreasing the mixed venous oxygen tension from 40 to 10 mmHg
B.
Destruction of alveolar septa and pulmonary capillaries by a disease known as alveolar emphysema
C.
Perfusing previously unperfused pulmonary capillaries
D.
None of the above
E.
Increasing PO2 in the alveoli from 100 to 500 mmHg
【单选题】The important raw material for hemoglobin synthesis during erythropoiesis is（ ）
A.
Erythropoietin
B.
Folic acid and vitamin B12
C.
Intrinsic factor
D.
Protein and iron
E.
Androgen
【单选题】The proximal convoluted tubules reabsorb how much percentage of filtered water?（ ）
A.
40%
B.
50%
C.
25%
D.
90%
E.
65%
【单选题】When it is cold, thyroid hormone increases because of（ ）
A.
Neuro-humoral regulation
B.
Humoral regulation
C.
Feedback adjustment
D.
Self-regulation
E.
Neuromodulation
【单选题】The thermal equivalent of oxygen of food is（ ）
A.
The energy released when food is oxidized to consume 1 liter of oxygen
B.
1 gram of energy released when food is oxidized
C.
1 gram of heat produced when food is burned outside the body
D.
1 gram of energy released by food during its metabolism in the body
E.
Energy released when 1 liter of oxygen is consumed by oxidizing 1 gram of food