Why do a chicken embryo and a cow embryo look very similar even though the adults do not?
they are not related, but still have similar development.
they are distantly related, so their development is similar.
the embryos mutate in utero to form different structures.
the genetic makeup of the two species is similar.

Which best describes how the common cold spreads in the human body? a bacteria burst out of normal cells killing them b viruses replicate inside respiratory cells c bacteria inject dna into normal cells d viruses insert dna into bacteria

Theories basic to all of the life sciences include the germ theory of disease. theory of evolution by natural selection. o two of these answers are correct none of these answers are correct o cell theory.

1. emigration the movement of people from one place to another 2. immigration a situation in which resources are being used up at a faster rate than they can be replenished 3. migration the leaving of one's homeland to settle in a new place 4. overpopulation the movement of people to a new country 5. sustainable development a situation in which the birth rate is not sufficient to replace the existing population 6. underpopulation the ability to meet current needs without reducing the ability to meet future needs 7. unsustainable development the increase in the population of a city 8. urbanization a situation in which the number of people exceeds the available natural resources in an area