Three primary germ layers are formed during `ul("morula")` stage of embryonic development.

Study the given differences between primary sludge and activated sludge and select the incorrect ones. Primary Sludge Activated sludge (i) It is sludge formed during primary sewage treatment. It is sludge formed during secondary sewage treatment. (ii) It possesses flocs of decomposer microbes. It does not possess flocs of decomposer microbes. (iii) It does not require aeration. Formation of activated sludge requires aeration. (iv) A lot of decomposition occurs during formation of primary sludge. Very little decomposition occurs during formation of activated sludge.

Which germ layer forms the nervous system?

Where is morula formed in humans? Explain the process of its development from zygote.

Which opening connects left and right atria during embryonic development?

Which germ layer forms the nervous system ?

Which germs layers develop into liver and pancreas.

What are the three germinal layers in an embryo? Write the name of few structures developed from these layers.