A species of bird has slight variations in its beak size and shape. Some individuals with bigger beaks are better at cracking seeds. Some individuals with narrower beaks are better at hunting for bugs. An invasive species is introduced that hunts all of the bug population, wiping out that food source for the birds, so all they are left with is seeds. In one to two sentences, explain how genetic variation from sexual reproduction can save this species from extinction.

Ascientist is investigating the effects of salinity on fish development. he places fertilized fish eggs in an aquarium that contains low salinity and observes their development. what factor would improve experimental design the most? place the fish eggs in the open ocean because that is the natural habitat include another aquarium that has normal salinity to compare to the low salinity aquarium include an aquarium that replaces salt with sugar to confirm that the effects are specific to salt grow algae with the fish eggs in order to provide adequate nutrients to the developing embryos

Which of the following are responsible for sending messages from the hypothalamus to the thalamus?

Which statement best describes the first stage of cellular respiration? check all that apply