Standing still and at attention for long periods can result in inadequate venous return. The effects of this can be seen when even young and healthy soldiers sometimes faint when standing at attention for long periods. Which of the following is NOT occurring to promote return of blood from the venous system in this situation?
A. sympathetic activation of smooth muscle in large veins
B. skeletal muscle activity compressing veins and forcing blood flow
C. one way flow in the venous system due to valves
D. ventricular contraction
B. skeletal muscle activity compressing veins and forcing blood flow
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The structure where fertilization takes place is the ____
a. ovary b. oviduct c. oviduct d. cervix e. uterus
The accompanying figure shows data on composite values for beak size, beak shape, and body size for the medium ground finch (Geospiza fortis) inhabiting Daphne Major. Complete data sets were collected from 1973 onward
For each of the three graphs in the accompanying figure, the 95% confidence intervals are shown as vertical bars extending above and below each data point for each year. The fact that many of these 95% confidence intervals do not overlap with the data from 1973 (the original reference point for this study) do not overlap reveals that ________. A) no detectable change in these phenotypes was measured B) no evolution can be documented C) detectable change in phenotypes was observed, but the changes were not heritable D) detectable evolution by natural selection did occur E) None of these is an accurate statement.
When the generative cell divides, the daughter cells are sperm cells
____________________ Indicate whether the statement is true or false.
A scientist performs an experiment in which they create an artificial cell with a selectively permeable membrane through which only water can pass. They inject a 5M solution of glucose into the cell and then place the cell into a beaker containing 10M glucose. What effect do you expect to observe?
A. No net change in cell weight B. Water moves out of the cell C. Water moves into the cell D. Glucose moves into the cell E. Glucose moves out of the cell