In goats, a beard is produced by an autosomal allele that is dominant in males and recessive in females. If  cross the beardless female with heterozygous beard male, what will be the proportion of female beard in F1 generation?

#Question id: 34128

#Unit 7. System Physiology – Animal

#Question id: 2800

#Unit 2. Cellular Organization

When chromatin is extracted from nuclei and viewed in the electron microscope, its form depends upon the salt concentration to which it is exposed. What is the form of chromatin when it is isolated in isotonic buffers, i.e. same salt concentration as in cells (about 0.15 M KCl)?

#Question id: 5646

#Unit 5. Developmental Biology

In order to test how sea urchin sperm bind to eggs, scientists isolated the egg receptor protein that binds to the sperm acrosomal protein called bindin. Plastic beads were coated with egg receptor for bindin (ERB1) from eggs of the sea urchin Strongylocentrotus purpuratus, and then the beads mixed with sperm from S. purpuratus or from the related species, S. franciscanus. The researchers counted how many sperm were bound to each bead. The results are shown in the graph below. Treatments:

A: S. purpuratus sperm mixed with S. purpuratus ERB1 beads

B: S. purpuratus sperm mixed with beads containing no ERB1 protein

C: S. franciscanus sperm mixed with S. purpuratus ERB1 beads

D: S. franciscanus sperm mixed with beads containing no ERB1 protein

 Based on the description of the experiment, which of the treatments would be considered a "control" treatment for S. purpuratus sperm binding?

#Question id: 23836

#Unit 2. Cellular Organization

#Question id: 23238

#Unit 2. Cellular Organization