What is the purpose of meiosis?
A. Meiosis allows for DNA to make a copy of itself so that cell division can produce daughter cells with identical DNA as the parent cell.
B. Meiosis produces gametes with half the number of chromosomes as the parent so when fertilization occurs the offspring will have the same number of chromosomes as the parent.
C. Meiosis produces gametes with the same number chromosomes as the parent allowing the fertilized zygote to have additional chromosomes.
D. Meiosis uses the transcribed mRNA as the information code to make the proteins necessary for the body.
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All of the following are true about mitosis except
A. DNA replication occurs prior to mitosis.
B. mitosis produced two genetically identical daughter cells.
C. mitosis plays a role in growth, repair, and asexual reproduction.
D. during mitosis, homologous chromosomes are paired to form tetrads.
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.
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
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