Mechanisms that move substances across membranes against concentration gradients are
a. calcium ions in the calcium pump.
b. membrane pumps.
c. ATP molecules.
d. passive transport.
e. facilitated diffusion.
B
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The precipitin test that is widely used for detecting antibodies against fungal infection is referred to as:
a. double immunodiffusion. b. counterimmunoelectrophoresis. c. particle agglutination. d. enzyme immunoassay.
At least some of the cells of a mammalian heart in the final phase of development would most likely be
A. undergoing apoptosis B. dividing rapidly C. expressing segmentation genes D. expressing cardiac-specific transcription factors E. either undergoing apoptosis or expressing cardiac-specific transcription factors
During which step of urine formation will water, glucose and amino acids be returned to the blood? a. Urination b. None of these choices
c. Tubular reabsorption d. Glomerular filtration e. Tubular secretion
The cells of a gametophyte are
A) tetraploid. B) haploid. C) triploid. D) diploid. E) unable to divide by mitosis.