. In a hypothetical situation, a certain species of flea feeds only on pronghorn antelopes. In rangelands
of the western United States, pronghorns and cattle often associate with one another. If some of these
fleas develop a strong preference, instead, for cattle blood and mate only with fleas that, likewise,
prefer cattle blood, then over time which of these should occur, if the host mammal can be
considered as the fleas' habitat?
1. reproductive isolation
2. sympatric speciation
3. habitat isolation
4. prezygotic barriers
a. 1 only
b. 2 and 3
c. 1, 2, and 3
d. 2, 3, and 4
e. 1 through 4

The dna in a cell’s nucleus encodes proteins that are eventually targeted to every membrane and compartment in the cell, as well as proteins that are targeted for secretion from the cell. for example, consider these two proteins: phosphofructokinase (pfk) is an enzyme that functions in the cytoplasm during glycolysis. insulin, a protein that regulates blood sugar levels, is secreted from specialized pancreatic cells. assume that you can track the cellular locations of these two proteins from the time that translation is complete until the proteins reach their final destinations.for each protein, identify its targeting pathway: the sequence of cellular locations in which the protein is found from when translation is complete until it reaches its final (functional) destination. (note that if an organelle is listed in a pathway, the location implied is inside the organelle, not in the membrane that surrounds the organelle.)

During which phase does earth see more than half of the moon's surface? 1)first quarter2)third quarter3)waxing gibbous4)waning crescent

Twin boys have girlfriends one of the couples have a baby would the dna of the lil baby be the same as the couples dna bc the boys are identical twins