Following statements are regarding to recognition of sperm by mammalian zona pellucida.

A. Sperm that have undergone the acrosome reaction bind directly to zona protein ZP2 and begin making a channel toward the oocyte.

B. Sperm with an intact acrosome bind to ZP2; they undergo the acrosome reaction on the zona pellucida and then transfer their binding to ZP3.

C. When a sperm reaches the oocyte and fuses with it, the cortical granules release proteins that digest portions of ZP2 and ZP3, making them nonfunctional and prevent polyspermy.

D. When a sperm reaches the oocyte and fuses with it, the cortical granules release proteins that digest ZP3 only, not ZP2 because ZP2 involve in the process of slow block to polyspermy.

Which of the above statements are correct?

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#Question id: 18078

#Unit 9. Diversity of Life Forms

Which of the following can be found in gymnosperms? 

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#Question id: 19829

#Unit 12. Applied Biology

At the site of infection in plants accumulation of which compounds leads to host cell death

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#Question id: 10596

#Unit 10. Ecological Principles

In a experimental population the birth rate is 18 per 1000 and death rate is 14 per 1000. Size of population is 10,000 at time t then what will be size of population at time t+1?

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#Question id: 24576

#Unit 10. Ecological Principles

The birth of 100 cockroaches to a population of 1,000 would represent a birth rate. Similarly, the death of 50 cockroaches in a population of 1,000 would be a death rate, d, per individual per week. Calculate the rate of change in a population per unit time ?

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#Question id: 2264

#Unit 2. Cellular Organization

Plants differ from animals in that plants have