#Question id: 19222
#Unit 12. Applied Biology
#Question id: 5538
#Unit 5. Developmental Biology
The first truly vertebrate phase of development is manifested by the formation of the
#Question id: 787
#Unit 1. Molecules and their Interaction Relevant to Biology
Which of the following statement is INCORRECT with respect to the structure of DNA?
#Question id: 5672
#Unit 5. Developmental Biology
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?
#Question id: 5010
#Unit 11. Evolution and Behavior
Which of the following steps has not yet been accomplished by scientists studying the origin of life?