What are karl von baer's four developmental principles?

Explanation:

1. During the development of the embryo, first, there is the appearance of general characters followed by the appearance of special characters. 

2. The specialized characters are formed from the more generalized forms. 

3. the embryo of any given organisms becomes different from other species. 

4. there is no resemblance between the embryos of the different organism at later stages of development. 

answer: - few nutrients

high pressure

low temperatures

explanation: 1. few nutrients:   open-ocean zone is located way far from the land, which is the main source of the essential nutrients.2. high pressure: pressure increases by 1 atmosphere for every 10 meters increase in depth.3. ample sunlight: a large fraction of the sunlight is reflected back to the atmosphere from the sea surface. 4. varying salinity: below the thermocline, the water is isolated from the atmosphere so the salinity remains stable over the year.5. low temperatures:   the temperature of open-ocean zone ranges from a low of -2°c to an average of 17°c

the match duh

explanation: