An embryo grows into a multicellular organism made of a wide variety of cell types. how does the variation in cell types occur

about 40,000,000 results (0.81 seconds)  

search results

what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.

he forelimbs below belong to four species that descended in a direct line from the ancestral mammal shown above. of the four descendants shown, which species most likely appeared earliest in evolutionary history?

the correct answer is sex-linked recessive.

i just took the test