#Question id: 15609
#Unit 12. Applied Biology
#Question id: 2903
#Unit 2. Cellular Organization
There are five known families of enzyme complexes that actively move or displace nucleosomes, hydrolyzing ATP in the process, three of which are particularly important in transcriptional activation. Which of the following statement is/are correct regarding these nucleosome remodeling complexes?
I. SWI/SNF remodels chromatin so that nucleosomes become more irregularly spaced, and stimulate the binding of transcription factors. It includes a bromodomain near the C-terminus of the active ATPase subunit, which interacts with acetylated histone tails.
II. Some members of a family, SWR1, are involved in deposition of the H2A.Z histone variant in transcriptionally inactive chromatin.
III. NURF, a member of the ISW1 family, remodels chromatin in ways that complement and overlap the activity of SWI/SNF. These two enzyme complexes are crucial in preparing a region of chromatin for active transcription.
#Question id: 18865
#Unit 13. Methods in Biology
#Question id: 7034
#Unit 5. Developmental Biology
Gastrulation in the frog begins at a point on the embryo surface roughly 180° opposite the point of sperm entry with the formation of a dimple called the:
#Question id: 14756
#Unit 5. Developmental Biology