Which of the following is a characteristic of cancer cells?
A. They have shorter cell cycles as compared to normal, healthy cells.
B. They have higher rates of transcription than normal, healthy cells.
C. They have lower rates of mitosis when compared to normal, healthy cells.
D. They have more mitochondria than normal, healthy cells.
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Nitric oxide is cellular signaling molecules involved in the physiological processes in the human body. One of its roles is as a cardiovascular signaling molecule. Which of the following is a reason why nitric acid causes blood vessels to dilate?
A. It causes the smooth muscle cells in the blood vessel walls to relax.
B. It prevents cyclic GMP production by suppressing guanylyl cyclases.
C. It is rapidly swept away by the blood stream.
D. None of these.
Which process occurs when cells convert information from an external signal to another form?
A. signal amplification
B. signal dependence
C. signal transduction
D. signal transformation
Three signaling mechanisms are listed below:I. Endocrine signalingII. Paracrine signalingIII.Autocrine signalingWhich signaling mechanism involves hormones binding to target cells?
A. I
B. I and II
C. II and III
D. I, II, and III
Which of the following best explains how plasmodesmata function for cell communication?
A. Cells communicate over long distances using hormones.
B. Cells communicate with each other by cell-to-cell contact.
Cells communicate using ligand-ion channels.
D. Cells communicate changing the shape of the protein receptor.
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