#Question id: 15974
#Unit 12. Applied Biology
#Question id: 14698
#Unit 13. Methods in Biology
#Question id: 5678
#Unit 5. Developmental Biology
Following process and their mechanism during fertilization in mammals.
a. Rheotaxis |
i.A sensing mechanism in which, the oocyte and its accompanying cumulus cells secrete molecules that attract capacitated sperm toward the egg during the last stages of sperm migration |
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b. Chemotaxis |
ii.It is a transient event, and sperm are given a relatively brief window of competence during which they can successfully fertilize the egg. |
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c. Capacitation |
iii.it is the ability to sense temperature difference and preferentially swim from cooler to warmer sites is found only in capacitated sperm. |
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d. Thermotaxis |
iv.Sperm receive long-distance directional cues from the flow of liquid from the oviduct to the uterus and they will migrate against the direction of the flow—using CatSper calcium channels to sense calcium influx and monitor the direction of the current |
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Which of the following option is correct?
#Question id: 4501
#Unit 3. Fundamental Processes
According to Models of termination: torpedo and allosteric, which one is now the favored and why;
A. The Rat1 enzyme is very processive and quickly degrades the RNA in a 5’ -to-3’ direction, until it catches up to the still-transcribing polymerase from which the RNA is being spewed.
B. Termination depends on a conformational change in the elongating polymerase that reduces the processivity of the enzyme leading to spontaneous termination soon afterward.
#Question id: 15300
#Unit 5. Developmental Biology