#Question id: 5678
#Unit 5. Developmental Biology
Following process and their mechanism during fertilization in mammals.
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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: 19071
#Unit 6. System Physiology – Plant
#Question id: 11271
#Unit 10. Ecological Principles
Autotrophs in the aquatic ecosystem, unlike their counterparts in the terrestrial ecosystem are mostly microscopic and very low in indigestible (to the herbivores) matter. Following some observation are given?
A) Tropic level transfer efficiency is greater in aquatic ecosystem than terrestrial ecosystem
B) Tropical forest herbivores have higher consumption efficiencies than grassland herbivores
C) Flow of energy and nutrient is rapidly in aquatic ecosystem than terrestrial
D) Production efficiency of higher tropic level is greater than lower tropic level
#Question id: 10410
#Unit 6. System Physiology – Plant
#Question id: 961
#Unit 1. Molecules and their Interaction Relevant to Biology
Which type of organisms can eliminate excess nitrogen by the direct excretion of ammonia?